JP6650137B2 - Wireless sensor terminal - Google Patents

Description

  The present invention relates to a wireless sensor terminal suitable for use in a case where the wireless sensor terminal is attached to a place exposed to a severe external environment such as a bridge, for example, at high temperature, high humidity, and salt damage for a long time.

  For example, to maintain road infrastructure such as bridges, tunnels, incidental roads, and slopes, wireless sensor terminals are installed on those bridges, etc., and a sensor network system that collects sensor outputs sent from the wireless sensor terminals Is considered.

  Since this type of wireless sensor terminal is to be installed in a place that is exposed to a severe external environment such as high temperature, high humidity, and salt damage for a long period of time, a highly durable package structure is required.

  As this type of wireless sensor terminal, for example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2013-122718) proposes a wireless sensor node having a sealed structure using a package made of ceramic. That is, in the wireless sensor node disclosed in Patent Document 1, as shown in FIG. 13, for example, a vibration power generation element or a solar power generation element is provided in a cavity of a package 20 configured by stacking a plurality of ceramic layers. A power generation element 30 that generates power by receiving power generation energy depending on the environment, and a power supply IC 31 and a DC power supply that constitute a conversion circuit that converts the power generated by the power generation element 30 into DC power that can be supplied to a subsequent circuit. / DC converter 32, a power storage element 33 for storing and charging / discharging the DC power obtained by the conversion circuit, an acceleration sensor 34, and circuit units 35 and 37 for converting a detection signal of the acceleration sensor 34 into a wireless signal. And an antenna 38 for radiating a radio signal as a radio wave. The lid member 21 is integrally bonded to the package 20 to hermetically seal the cavity. Patent Literature 1 describes that the lid member 21 may be made of ceramic in addition to being made of metal.

  The wireless sensor node disclosed in Patent Literature 1 has a feature that, by using a package having an airtight structure made of ceramic, the wireless sensor node has resistance to an external environment at an installation place and does not depend on an external power supply.

JP 2013-122718 A

  As described above, in a wireless sensor terminal in which a power supply unit including a power generation element is housed in a sealed package, a power switch that is exposed to the outside is not provided in order to form a sealed package. The power supply voltage from the power supply section including the above is always supplied to each circuit section in the sealed package.

  When the wireless sensor terminal is installed at the place of use, power is generated by a power generating element that generates power in accordance with the environment, the power storage element is charged via a charge control circuit, and a power supply voltage that is always equal to or higher than a predetermined value. Is obtained, and the device operates normally.

  By the way, it is known that a power storage element composed of a battery such as a lithium ion battery, for example, is significantly deteriorated once in an overdischarge state in which the voltage drops to a specified voltage (discharge end voltage) or lower. Therefore, usually, the charge control circuit is provided with a control function for preventing the voltage of the power storage element from falling below a predetermined voltage.

  However, when this type of wireless sensor terminal is stocked in a warehouse or the like before use, it is not necessarily placed in an environment where the power generating element can generate power. In the wireless sensor having the configuration, the power supply voltage stored in the power storage element is consumed in the circuit unit in the sealed package. For this reason, when this type of wireless sensor terminal is stocked in a warehouse or the like for a long time, there is a fear that overdischarge occurs in which the storage voltage of the power storage element drops below a predetermined voltage.

  Therefore, for this type of wireless sensor terminal, check the period during which the power generating element is placed in an environment where it cannot generate power so that overdischarge, in which the storage voltage of the power storage element drops below the predetermined voltage, does not occur. Therefore, there is a problem that after a predetermined period of time, troublesome inventory management such as moving to an environment where power generation can be performed is required.

  In addition, in this type of wireless sensor terminal, when an internal circuit or element is deteriorated from the outside, it cannot be grasped. Furthermore, when a malfunction occurs in the operation of the wireless sensor terminal, the only option is to break the sealed package and analyze the malfunction of the internal circuit.

  Furthermore, in the conventional wireless sensor terminal, since there is no terminal portion exposed to the outside, it is not possible to receive power supply from the wireless sensor terminal or to transmit data to the wireless sensor terminal to receive it. Was.

  An object of the present invention is to provide a wireless sensor terminal capable of solving the above problems.

In order to solve the above problems, the invention of claim 1 is:
At least, a sensor, a signal processing circuit system including a wireless transmission circuit that wirelessly transmits information detected by the sensor ,
A first antenna connected to the wireless transmission circuit;
A power generation unit for generating power, a power storage element storing a storage voltage higher than a specified voltage , and receiving the power generated by the power generation unit, controlling the storage voltage so as not to be lower than the specified voltage. A power supply system that includes a power supply control circuit that generates a power supply voltage while storing power in the element ;
A switch circuit provided in a power supply path between the signal processing circuit system and the power supply system, the initial state being OFF, and a self-holding ON state when switched ON,
A power-on control circuit for turning on the switch circuit;
A second antenna connected to the power-on control circuit;
Is a wireless sensor terminal provided in a hermetically sealed package that is hermetically sealed by joining the lid portion ,
The power-on control circuit switches the switch circuit on based on a signal received from outside through the second antenna, and provides a wireless sensor terminal.

In the wireless sensor terminal according to the first aspect of the present invention, since the switch circuit is off in the initial state, the power supply path between the power supply system and the signal processing circuit system is shut off. Therefore, the storage voltage of the storage element is not discharged, and the storage voltage is prevented from falling below the specified voltage (discharge end voltage) even when the power generation unit does not generate power.

In the present invention, when a power-on signal transmitting device, for example , outside the sealed package, is wirelessly connected to the second antenna, the power-on control circuit executes a predetermined process.

That is, when , for example, a power-on signal transmission device is wirelessly connected to the second antenna, the power-on control circuit includes a switch circuit provided in a power supply path that supplies a power supply voltage to each unit including the wireless transmission circuit. and switching control to turn on based on the reception of signals from the outside through the second antenna.

  Therefore, the switch circuit is turned off before the wireless sensor terminal is installed at the predetermined installation location, and the switch circuit is turned on after the wireless sensor terminal is installed at the installation location, so that the power storage element does not become lower than the discharge end voltage. Can be

According to the present invention, in a wireless sensor terminal using a power storage element for a power supply system, the power supply system and the signal processing circuit in the closed package have a hermetically sealed package in which a lid portion is hermetically sealed and joined. Since a switch circuit that is turned off in the initial state is provided between the signal processing circuit system and the system, it is possible to prevent the storage voltage of the storage element from being consumed by the signal processing circuit system. At the start of use of the wireless sensor terminal, the switch circuit is turned on by the power-on control circuit by wirelessly connecting the second antenna to an external device, and the power supply voltage from the power supply system is transmitted to the sensor and wirelessly. Power can be supplied to a signal processing circuit system including a circuit .

Therefore, according to the present invention, by surely preventing the voltage of the storage element from falling below the specified voltage (discharge end voltage) and controlling the switch circuit to be turned on from the outside at the start of use , the inside of the sealed package can be prevented . an effect that can be controlled to supply a power supply voltage to each part.

1 is a diagram illustrating a configuration example of an embodiment of a wireless sensor terminal according to the present invention. It is a block diagram showing an example of an electronic circuit composition of an embodiment of a wireless sensor terminal by this invention. FIG. 2 is a diagram for describing a configuration example of an embodiment of a wireless sensor terminal according to the present invention. It is a figure for explaining an example of composition of an important section of an embodiment of a wireless sensor terminal by this invention. FIG. 2 is a diagram for describing a configuration example of an embodiment of a wireless sensor terminal according to the present invention. It is a figure for explaining a sealing combination method in an embodiment of a wireless sensor terminal by this invention. FIG. 2 is a diagram illustrating a configuration example of a main part and a relationship with an external device in the embodiment of the wireless sensor terminal according to the present invention. FIG. 2 is a diagram illustrating a configuration example of a main part and a relationship with an external device in the embodiment of the wireless sensor terminal according to the present invention. FIG. 9 is a diagram illustrating a flowchart for explaining the operation of the example in FIG. 8. FIG. 2 is a diagram illustrating a configuration example of a main part and a relationship with an external device in the embodiment of the wireless sensor terminal according to the present invention. FIG. 11 is a diagram illustrating a flowchart for explaining the operation of the example in FIG. 10. FIG. 11 is a diagram used to explain another configuration example of the embodiment of the wireless sensor terminal according to the present invention. FIG. 11 is a diagram for describing a configuration example of a conventional wireless sensor terminal.

  Hereinafter, an embodiment of a wireless sensor terminal according to the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration example of a wireless sensor terminal 100 according to an embodiment of the present invention. The wireless sensor terminal 100 of this embodiment is configured such that electronic circuit components constituting the wireless sensor terminal 100 are provided in a package 101 having a substantially rectangular parallelepiped shape in appearance. FIG. 1B is a diagram illustrating the wireless sensor terminal 100 when the package 101 is viewed from a direction orthogonal to a surface on the side where external light is taken. FIG. 1A is a cross-sectional view taken along the line AA in FIG. 1B and is a diagram for describing a configuration example in the package 101.

  The package 101 is made of a highly durable material capable of maintaining the performance of the internal circuit even when exposed to a severe external environment such as salt damage, high temperature and high humidity for a long time. It is made of a ceramic material having toughness, light weight, and electrical insulation as compared with. As shown in FIG. 1A, the package 101 includes a box-shaped package main body 102 having an opening at an upper portion and having a concave portion 104 surrounded by a wall portion 102W, and a lid portion 103.

  In this embodiment, the package body 102 has a configuration in which LTCC (Low Temperature Co-fired Ceramics) substrates are laminated. The lid 103 is made of a translucent ceramic material. The lid portion 103 is joined to the package body 102 at the end surface of the wall portion 102W via a joining member 105 made of a low-melting glass melt, which will be described in detail later. The structure is hermetically sealed.

  In this embodiment, the package body 102 includes a power supply system including a self-contained power generation unit, and a plurality of sensors such as a vibration sensor and a temperature sensor for detecting external environmental factors and wirelessly transmitting the detection output. An electronic circuit including a signal processing circuit system is housed. The main components of the electronic circuit are housed in the recess 104 of the package body 102. However, as will be described later, an antenna for wirelessly connecting to the outside, such as an antenna for wireless communication, is provided to be embedded in the wall portion 102W of the package body 102 in this embodiment. In this embodiment, the embedded antenna is formed of a conductor filled in a via penetrating at least one of the ceramic layers, is formed in a pattern between the ceramic layers, or is formed by a combination of a via and a pattern. It is formed.

[Example of electronic circuit configuration]
FIG. 2 is a block diagram illustrating a configuration example of an electronic circuit of the wireless sensor terminal 100 according to the present embodiment, and includes a power supply system 200 and a signal processing circuit system 210. As shown in FIG. 2, the power supply system 200 of the wireless sensor terminal 100 according to this embodiment includes a solar cell module 202 as an example of a first power generation unit, A vibration power generation element 203 as an example and a storage capacitor 204 as an example of a power storage element are connected to each other.

  In this embodiment, the solar cell module 202 has a rectangular shape in which one or a plurality of flat solar cells are arranged in a plane. The vibration power generation element 203 is configured as a MEMS (Micro Electro Mechanical System) using a piezoelectric element, for example. Note that the vibration power generation element 203 can also be used as a vibration sensor 212 described later.

  In this example, the storage capacitor 204 is constituted by one capacitor (capacitor), but may be constituted by a plurality of capacitors. In this example, a lithium ion capacitor (LiC) is used as the storage capacitor 204. The storage capacitor 204 may be configured by an electric double layer capacitor. Further, as the power storage element, a secondary battery such as a lithium ion battery may be used instead of the power storage capacitor.

  In this example, the power supply control circuit 201 is configured as an energy management LSI (Large Scale Integration), and receives a power generation voltage from the solar cell module 202 or a power generation voltage from the vibration power generation element 203 to control the wireless sensor terminal 100. The power supply voltage Vcc is generated, and power is stored in the power storage capacitor 204 with the surplus power. When the power supply control circuit 201 cannot generate the power supply voltage Vcc from the power generation voltage from the solar cell module 202 or the power generation voltage from the vibration power generation element 203, the power supply control circuit 201 converts the storage voltage stored in the power storage capacitor 204 into the power supply voltage Vcc. To be used as The power supply control circuit 201 monitors the storage voltage of the storage capacitor 204, and does not drop below a predetermined voltage (discharge end voltage), for example, so that the wireless sensor terminal 100 can maintain its operation with a long life. The power supply control is performed.

  The power supply control circuit 201 includes a DC-DC conversion LSI, and generates a power supply voltage Vcc equal to or higher than a circuit operation voltage from a power generation voltage from the solar cell module 202, a power generation voltage from the vibration power generation element 203, and a storage voltage of the storage capacitor 204. It is generated and output through the storage capacitor 204. In this example, for example, the circuit operation voltage is set to 2.2 volts, and the power supply control circuit 201 controls the storage voltage of the storage capacitor to be 2.2 to 3.8 volts. In this case, the power supply control circuit 201 is configured to control whether to operate (enable or not) the power supply control process based on a command by a control signal from the process control circuit 211.

  In this embodiment, the power supply system 200 further transmits the generated power supply voltage Vcc to a switch circuit 205 provided in a supply path from the power supply system 200 to the signal processing circuit system 210 and a power-on control circuit 206 And a power-off control circuit 207. The switch circuit 205 is turned on and off by control signals from the power-on control circuit 206 and the power-off control circuit 207, respectively. The power-on control circuit 206 and the power-off control circuit 207 are connected to antennas 301 and 302, respectively. The antennas 301 and 302 are for wirelessly connecting to the outside of the package 101 of the wireless sensor terminal 100, and each constitute a second antenna.

  In this embodiment, the antennas 301 and 302 are provided in the package 101 so as not to be exposed to the outside of the package 101 so as not to impair the airtightness of the wireless sensor terminal 100. In this example, FIG. As shown in (B), it is embedded in the wall 102W of the package body 102 and provided.

  Then, each of the power-on control circuit 206 and the power-off control circuit 207 performs a predetermined process as described below by receiving a signal from outside through the antennas 301 and 302. That is, a circuit portion including the switch circuit 205, the power-on control circuit 206, and the power-off control circuit 207 forms an example of a specific circuit.

  When detecting a predetermined signal from the outside of the package 101 of the wireless sensor terminal 100 through the antenna 301, the power-on control circuit 206 controls the switch circuit 205 to be turned on, and outputs the power supply voltage Vcc generated by the power supply system 200 to the signal. It is configured to supply to the processing circuit system 210. In this example, when a signal having a frequency of, for example, 890 kHz to 930 kHz is received and detected through the antenna 301 as a predetermined signal, the power-on control circuit 206 controls the switch circuit 205 to be turned on. The antenna 301 is configured to efficiently receive a signal having the frequency of 890 kHz to 930 kHz.

  When detecting a predetermined signal from the outside via the antenna 302, the power-off control circuit 207 controls the switch circuit 205 to be turned off, and outputs the power supply voltage Vcc generated by the power supply system 200 to the signal processing circuit system 210. It is configured to shut off the supply. In this example, when a signal having a frequency of, for example, 100 kHz to 130 kHz is received and detected through the antenna 302 as a predetermined signal, the power-off control circuit 207 controls the switch circuit 205 to be turned off. The antenna 302 is configured to efficiently receive a signal having the frequency of 100 kHz to 130 kHz.

  In this example, the antennas 301 and 302 have a configuration of induction coils 301a and 302a, and a device for transmitting a power-on signal or a power-off signal to a wall of the package body 102 in which the coils are embedded. For example, when the device is approached within several centimeters, it is configured to be able to receive a power-on signal and a power-off signal from the device or the device.

  Note that the configurations and operations of the power-on control circuit 206 and the power-off control circuit 207 will be further described later.

  In the signal processing circuit system 210, a plurality of sensors such as a vibration sensor 212, a temperature sensor 213, and a failure / deterioration diagnosis sensor 214 are connected to a processing control circuit 211 for controlling the entire wireless sensor terminal 100. In addition, a memory 215, a wireless transmission circuit 216, an RFID circuit 217, and a data demodulation circuit 218 are connected to each other.

  The power supply voltage Vcc generated by the power supply system 200 is supplied to the processing control circuit 211, the vibration sensor 212, the temperature sensor 213, the failure / deterioration diagnosis sensor 214, the memory 215, the wireless transmission circuit 216 via the switch circuit 205. The power is supplied to the RFID circuit 217 and the data demodulation circuit 218, and is also supplied to the power transmission control circuit 219.

  In this example, the processing control circuit 211 is configured by, for example, an MPU (Micro Processor Unit).

  The vibration sensor 212 detects a vibration at a place where the wireless sensor terminal 100 is attached as a detection target attribute, and supplies information of the detected vibration to the processing control circuit 211. In this example, the vibration sensor 212 has a configuration of a MEMS sensor. ing. The temperature sensor 213 detects the temperature in the concave portion 104 of the package body 102 of the wireless sensor terminal 100 as a detection target attribute, and supplies information of the detected temperature to the processing control circuit 211. It is configured as a sensor.

  In this example, the failure / deterioration diagnosis sensor 214 checks the current flowing through each circuit of the signal processing circuit system 210 to perform failure / deterioration diagnosis of each circuit of the signal processing circuit system 210. That is, the power supply voltage Vcc is supplied to each circuit unit of the vibration sensor 212, the temperature sensor 213, the memory 215, the wireless transmission circuit 216, the RFID circuit 217, and the data demodulation circuit 218 of the signal processing circuit system 210. The current of the unit is a constant value unless it is in an abnormal / failure state. Therefore, although not shown in FIG. 2, for example, a resistor is inserted into a power supply wiring portion of each circuit portion of the signal processing circuit system 210, and a current is monitored as a voltage between both ends of the inserted resistor. The occurrence of an abnormal / failure state can be detected. Instead of each circuit unit, each circuit unit may be divided into a plurality of block units, and occurrence of an abnormal / failure state may be detected in each of the divided block units. The failure / deterioration diagnosis sensor 214 supplies the result information of the failure / deterioration diagnosis to the processing control circuit 211.

  The failure / deterioration diagnosis sensor 214 may supply the detected failure / deterioration result information to the processing control circuit 211 only when the failure / deterioration is detected. Further, the processing control circuit 211 may periodically access the failure / deterioration diagnosis sensor 214 and acquire the failure / deterioration diagnosis result information detected by the failure / deterioration diagnosis sensor 214 at that time. Good. Note that information on the time at which the failure / diagnosis was performed is added to the failure / deterioration diagnosis result information supplied from the failure / deterioration diagnosis sensor 214 to the processing control circuit 211. Further, the time from when the processing control circuit 211 receives the result information of the failure / deterioration diagnosis is replaced by the time at which the failure / deterioration diagnosis was performed without adding time information to the information from the failure / deterioration diagnosis sensor 214. May be associated with each other.

  The memory 215 temporarily stores the transmission information generated by the processing control circuit 211. The memory 215 supplies the temporarily stored transmission information to the wireless transmission circuit 216 based on the control of the processing control circuit 211.

  The sensor transmitting antenna 310 is connected to the wireless transmitting circuit 216. The wireless transmission circuit 216 converts the transmission information received through the memory 215 into a signal of a predetermined modulation scheme under the control of the processing control circuit 211, and transmits the signal to the package 101 of the wireless sensor terminal 100 through the sensor data transmission antenna 310. Wirelessly to the outside.

  The sensor data transmitting antenna 310 constitutes a first antenna, and is provided in the package 101 so as not to be exposed to the outside of the package 101. In this embodiment, in particular, in this embodiment, FIGS. As shown in ()), it is embedded in the wall 102W of the package body 102 and provided.

  In this example, the wireless transmission signal transmitted from the sensor data transmission antenna 310 has a carrier frequency (carrier frequency) of, for example, 920 MHz. Then, the transmission signal from the wireless sensor terminal 100 is transmitted to a relay device installed within a range of, for example, several tens of meters, and the relay device transmits the sensor data from the wireless sensor terminal 100 via a mobile phone network or the Internet. Is supplied to the sensor data collection management device. For this reason, in this embodiment, the sensor data transmission antenna 310 is configured to be able to transmit the high frequency with a non-directional characteristic, for example, within a range of several tens of meters.

  The processing control circuit 211 has a time management function, takes in sensor data of vibration information and temperature information detected by the vibration sensor 212 and the temperature sensor 213 at predetermined predetermined timing, and generates transmission information. It is temporarily stored in the memory 215. Then, the processing control circuit 211 controls the transmission information temporarily stored in the memory 215 to be wirelessly transmitted from the sensor data transmission antenna 310 to the outside via the wireless transmission circuit 216. In this embodiment, generation of transmission information and wireless transmission based on sensor data taken in from the vibration sensor 212 and the temperature sensor 213 are intermittently executed based on time management in the processing control circuit 211.

The RFID circuit 217 receives the failure / deterioration diagnosis result information obtained from the failure / deterioration diagnosis sensor 214 by the processing control circuit 211 from the processing control circuit 211, collects the information, and stores the information in the built-in memory 217M. . In this example, the RFID circuit 217 and the processing control circuit 211 are connected by an I ² C (Inter-Integrated circuit) bus. In this example, the memory 217M is configured by an EEPROM (Electrically Erasable and Programmable Read Only Memory).

  The antenna 303 is connected to the RFID circuit 217. The antenna 303 is for wirelessly connecting to the outside of the package 101 of the wireless sensor terminal 100. When the RFID circuit 217 receives a signal for activating the RFID circuit 217 from outside the package 101 through the antenna 303, It is configured to perform a process of reading history information (history information to which time information is added and arranged in chronological order) of failure / deterioration result information stored in the memory 217M and transmitting the history information to the outside through the antenna 303. ing.

  The antenna 303 forms an example of a second antenna, and the RFID circuit 217 forms an example of a specific circuit. That is, the RFID circuit 217 obtains and collects failure / deterioration diagnosis result information from the processing control circuit 211 as a predetermined process, and transmits the collected failure / deterioration diagnosis result information to the external device via the antenna 303. Thus, a process of transmitting to the outside through the antenna 303 is executed. In this embodiment, the frequency of wireless transmission and reception between the RFID circuit 217 and the outside is, for example, 890 kHz to 930 kHz, and the antenna 303 is configured to transmit and receive this frequency.

  Note that, in this embodiment, the antenna 303 is provided in the package 101 similarly to the antennas 301 and 302, and in this embodiment, in particular, as shown in FIG. It is provided embedded in the wall 102W. This antenna 303 also has an induction coil 303a in this example, similarly to the above-described antennas 301 and 302, and the failure / deterioration diagnosis result information is externally provided on the wall of the package body 102 in which it is embedded. Is configured to receive a signal from the device or the device and to transmit a signal to the device or the device when the device or the device that obtains the request is approached, for example, within several cm. ing.

  The antenna 304 is connected to the data demodulation circuit 218. The antenna 304 is an example of a second antenna. The data demodulation circuit 218 is an example of a specific circuit. The data demodulation circuit 218 performs a predetermined process of receiving the sensor data from the outside via the antenna 304, demodulating the received sensor data, and supplying the demodulated sensor data to the processing control circuit 211. In this embodiment, the frequency of a signal (sensor data) wirelessly received by the data demodulation circuit 218 from the outside is, for example, 890 kHz to 930 kHz, and the antenna 303 is configured to receive this frequency. I have.

  Upon receiving the sensor data from the data demodulation circuit 218, the processing control circuit 211 temporarily stores the sensor data in the memory 215, and controls the wireless transmission circuit 216 to transmit the sensor data at a predetermined timing through the sensor data transmission antenna 310. .

In this embodiment, the antenna 304 is provided in the package 101 similarly to the antennas 301 and 302. In this example, as shown in FIG. It is embedded and provided. Then, the antenna 30 4, like the antenna 301 and 302 described above, in this example, is the construction of the induction coil 304a, the wall portion of the package body 102 in which it is embedded, transmitted from the external sensor data When the device or the terminal device is brought close to, for example, several cm or less, sensor data from the transmitting device or the terminal device can be received. Therefore, in this example, the antenna 304 does not need to be configured to receive a radio wave (electromagnetic wave) from a remote place.

  The antenna 305 is connected to the power transmission control circuit 219. The antenna 305 is an example of a second antenna, and the power transmission control circuit 219 is an example of a specific circuit. The power transmission control circuit 219 performs a predetermined process of supplying a power supply voltage by wireless transmission to an external device such as a sensor terminal outside the package 101 wirelessly connected via the antenna 305. In this embodiment, the frequency at which the power transmission control circuit 219 wirelessly transmits the power supply voltage to the outside is, for example, 100 kHz to 130 kHz, and the antenna 305 is configured to correspond to this frequency. .

  Note that, in this embodiment, the antenna 305 is provided in the package 101 similarly to the antennas 301 and 302, and in this embodiment, in particular, as shown in FIG. It is provided embedded in the wall 102W. And, in this example, the antenna 305 has a configuration of an induction coil 305a, and when an external sensor terminal or an external device approaches, for example, within 10 cm, to the wall of the package body 102 in which the antenna 305 is embedded. In addition, it is configured to electromagnetically couple with the external sensor terminal or the antenna of the external device. The power transmission control circuit 219 wirelessly supplies a power supply voltage to an external device such as an external sensor terminal through an antenna of an external device such as a sensor terminal external to the package 101 electromagnetically coupled to the antenna 305.

[Example of arrangement of electronic circuit components in package 101]
In this example, as shown in FIG. 1A, the inner surface of the wall portion 102W of the package body 102 on the concave portion 104 side is located on the concave portion 104 side from the bottom surface of the concave portion 104 to a predetermined height h1. It is configured to overhang. The height h1 is lower than the depth of the concave portion 104, that is, the height h0 corresponding to the distance from the bottom surface of the concave portion 104 to the end surface of the wall portion 102W of the package body 102 (h1 <h0). .

  Thus, a step portion 106 having a step shape is provided in the concave portion 104 of the package body 102 as shown in FIG. As shown in FIG. 1B, the stepped portion 106 is formed all over the inside of the four side walls 102W of the package body 102. Therefore, the concave portion 104 has a small concave portion 104a having a small sectional area surrounded by the step portion 106 and a large concave portion 104b having a large sectional area surrounded by the wall portion 102W other than the step portion 106.

  In this example, the electronic components and the signal processing circuit system constituting the power supply system 200 other than the solar cell module 202, the sensor data transmission antenna 310, and the antennas 301 to 305 are provided on the bottom surface inside the small recess 104a. Each electronic component constituting 210 is arranged. Note that FIG. 1A shows only the processing control circuit 211, the vibration sensor 212, and the temperature sensor 213 for convenience.

  As described above, in this embodiment, the package body 102 is configured by stacking LTCC substrates. As shown in FIG. 3, conductor patterns 107a, 107b, 107c, 107d,... Are provided between the LTCC substrates 102a, 102b, 102c, 102d,. , 102c, 102d,... Provided with vias 108a, 108b, 108c, 108d,. To do.

  The wall 102W made of the LTCC substrate is provided with a via filled with a conductor for electrical connection between the power supply control circuit 201 and the solar cell module 202 provided in the small recess 104a. In addition, an electrical connection with the terminal of the solar cell module 202 is made at the end face of the step portion 106.

  Then, as shown in FIGS. 1 and 4, the sensor data transmission antenna 310 is disposed in the package 101 so as to be embedded in the wall portion 102W of the package body 102. In this embodiment, the sensor data transmission antenna 310 includes two rod-shaped conductors 310a and 310b, and is configured to be non-directional. That is, in this example, the rod-shaped conductor 310a is arranged so that the axial direction thereof is in the direction along the height direction of the wall portion 102W, and the rod-shaped conductor 310b has the axial direction of the wall portion 102W. It is arranged to be in a direction orthogonal to the height direction of 102W.

  By arranging the two rod-shaped conductors 310a and 310b in this manner, the directional characteristics of the sensor data transmission antenna 310 are combined with the directional characteristics of the antenna constituted by each of the two rod-shaped conductors 310a and 310b. Therefore, it is possible to have almost omnidirectionality.

  These rod-shaped conductors 310a and 310b are formed by stacking the LTCC substrates to form the wall 102W, and filling the vias penetrating at least one of the plurality of layers of the LTCC substrate with the conductor to fill the wall 102W. To be housed within. Further, as shown in FIG. 3, the electrical connection between the rod-shaped conductors 310a and 310b and the wireless transmission circuit 216 is also a conductor pattern between the laminated LTCC substrates (in FIG. 1A, it is shown as a conductor pattern 107i). ).

  In this embodiment, the antennas 301, 302, 303, 304, and 305 are also arranged in the package 101 so as to be embedded in the wall 102W of the package body 102, as shown in FIG. Then, in this example, the antennas 301, 302, 303, 304 and 305 are respectively constituted by the induction coils 301a, 302a, 303a, 304a and 305a as described above. In this example, each of the induction coils 301a, 302a, 303a, 304a, and 305a is arranged such that the winding axis direction (direction of magnetic flux) of the coil is perpendicular to the wall surface of the wall 102W. I have.

  As a method of forming these induction coils 301a, 302a, 303a, 304a, and 305a in the wall 102W, for example, a method described in JP-A-2003-218626, WO2014-112243A1, or the like may be used. it can. Here, the description thereof is omitted.

Then, each of the induction coils 301a, 302a, 303a, 304a, and 305a constituting each of the antennas 301, 302, 303, 304, and 305, the power-on control circuit 206, the power-off control circuit 207, the RFID circuit 217, and the data demodulation The connection between the circuit 218 and the power transmission control circuit 219 is made by a conductor pattern between the laminated LTCC substrates, similarly to the electrical connection between the rod-shaped conductors 310a and 310b and the wireless transmission circuit 216.

  In the case of this example, the antennas 301 to 305 are respectively wirelessly coupled to the outside (electromagnetic coupling) with the four flat wall portions 102W1, 102W2, 102W3, and 102W4 constituting the wall portion 102W of the package 101 having a rectangular parallelepiped shape. ) Are arranged at positions where frequency differences are taken into account, and are configured so as not to interfere with each other as much as possible.

  That is, in this example, the induction coil 301a forming the antenna 301 for receiving a signal having a frequency of 890 kHz to 930 kHz, and the induction coil 301 forming the antenna 302 for receiving a signal having a frequency of 100 kHz to 130 kHz. Since the coils 302a have different frequencies from each other, they are provided in the same flat wall portion 102W1. Further, an induction coil 303a constituting an antenna 303 for transmitting and receiving signals having a frequency of 890 kHz to 930 kHz is provided in a flat wall portion 102W3 facing the flat wall portion 102W1.

  Further, an induction coil 304a constituting the antenna 304 for receiving a signal (sensor data) having a frequency of 890 kHz to 930 kHz is provided in the flat wall portion 102W2. The induction coil 305a constituting the transmitting antenna 305 having a frequency of 100 kHz to 130 kHz is provided at a position in the flat wall portion 102W2 that is separated from the antenna 304.

  In the wireless sensor terminal 100 of this embodiment, a specific circuit to which the embedded antennas 301 to 305 are connected is mounted on the outer wall surface of each of the flat wall portions 102W1 to 102W4 of the wall portion 102W of the package 101. Marks (markers) such as symbols, marks, and character displays corresponding to the functions are additionally displayed by, for example, printing, and serve as marks for recognizing the position and function of each antenna.

  Note that, in this example, the sensor data transmitting antenna 310 has the rod-shaped conductor 310a provided in the flat wall portion 102W4 where the antennas 301 to 305 are not provided, and the rod-shaped conductor 310b provided in the flat wall portion 102W4. The antenna 303 is provided at a position separated from the antenna 303.

  As described above, the solar cell module 202 of this embodiment has a rectangular flat plate shape, and the rectangular shape portion is similar to the concave portion 104. The size (area) of the solar cell module 202 is larger than the cross-sectional area of the small concave portion 104a of the concave portion 104 of the package main body 102 and smaller than the cross-sectional area of the large concave portion 104b. Then, the solar cell module 202 is housed in the large recess 104b in a state where its peripheral portion abuts on the end face portion of the step portion 106. Note that the difference between the height h0 and the height h1, that is, the depth (= h0−h1) of the large recess 104b is selected to be larger than the thickness of the solar cell module 202.

  Therefore, the solar cell module 202 fits completely in the large recess 104b of the package body 102. Therefore, when viewed from a direction orthogonal to the lid 103, the disposition position of the solar cell module 202 is the package main body 102 in which the two rod-shaped conductors 310a and 310b constituting the sensor data transmission antenna 310 are embedded. Of the wall 102W. That is, the sensor data transmission antenna 310 is in a state where transmission and reception of a radio wave can be performed without being disturbed by the solar cell module 202 at all.

  The solar cell module 202 is electrically connected to the power supply control circuit 201 provided in the small recess 104a via a conductor formed of a via provided in the wall 102W, and at the end face of the step 106, For example, the small recesses 104a are sealed by bonding with an adhesive or the like.

  In this case, the small recess 104a is filled with a predetermined filler 109, for example, a resin, so that at least the electronic circuit component does not touch the air layer. The filling of the filler 109 prevents the electronic circuit components disposed in the small recess 104a from coming into contact with the air layer, so that the electronic circuit components in the small recess 104a do not rust or corrode due to moisture or moisture. And can have long-term airtightness. In particular, the vibration sensor 212 and the vibration power generation element 203 are configured as MEMS elements. However, in combination with the airtightness of the package 101 described later, deterioration of the characteristics can be prevented and the performance can be maintained.

  Further, in this embodiment, the filler 109 is made of a high heat radiation material having a high thermal conductivity equal to or higher than the thermal conductivity of the ceramic material (LTCC substrate) forming the package body 102. Although the thermal conductivity of the package body 102 is 2 W / mk, in this example, a material having a thermal conductivity twice as high as 4 W / mk or more is used as the filler 109. Thus, the package 101 itself made of a ceramic material is a material having a high thermal conductivity and a high heat dissipation material, so that a rise in the temperature in the small recess 104a is suppressed, and the electronic circuit components in the small recess 104a operate stably. Can be secured.

  As an example of a method of filling the small recess 104a covered with the solar cell module 202 with the filler 109, for example, the inside of the small recess 104a is filled with a filler 109 made of a gel resin, A method is used in which the module 202 is joined at the step 106 so as to seal the small recess 104a. In this case, the electronic circuit components in the small recesses 104a may be prevented from contacting the air layer by the filler 109. Therefore, there may be a slight space gap between the electronic circuit components and the solar cell module 202.

  Further, as an example of a method of filling the small concave portion 104a covered with the solar cell module 202 with the filler 109, a part of the step portion 106 may be formed between the end surface of the step portion 106 and the side wall surface facing the small concave portion 104a. (Injection hole and air vent hole) are formed, the small concave portion 104a is covered with the solar cell module 202, and then the liquid filler 109 is injected through the hole of the formed step portion 106. When the filling is completed, a method of closing the hole formed in the stepped portion 106 may be used.

  As described above, the electronic circuit components are arranged in the small recesses 104a, the small recesses 104a are filled with the filler 109, and the small recesses 104a are hermetically sealed by the solar cell module 202. By sealingly joining the lid 103 to the main body 102, the recess 104 is sealed, and the package 101 becomes airtight.

  In this case, as described above, since the lid 103 needs to transmit light incident on the solar cell module 202 in the recess 104 as described above, in this embodiment, the lid 103 is made of a translucent ceramic (alumina). . This translucent ceramic material has toughness compared to glass, is lightweight, has electrical insulation, and has light transmission. FIG. 5 shows a comparison table of main characteristics of the translucent ceramic and the glass constituting the lid 103.

  As is clear from the table of FIG. 5, the lid portion 103 made of translucent ceramic has a higher thermal conductivity than glass, and also has a thermal conductivity of LTCC which is a ceramic material of the package body 102 (4 W / mk), so that even if the temperature of the space of the large concave portion 104b rises due to the incident light, there is an effect that the heat is efficiently radiated through the lid 103. Further, since the light-transmitting ceramic has higher heat resistance than glass, in this embodiment, the lid 103 made of the light-transmitting ceramic is used to take advantage of the high heat resistance to form the wall portion of the package body 102. A low-temperature and highly airtight sealing joint is made to the end face of 102W by, for example, local heating with a laser.

  Conventionally, when the package body 102 and the lid 103 are joined by using a joining member, heat is applied to the entire package body 102 and the lid 103 so as to be higher than the melting temperature of the joining member. Then, the joining member is melted, and then cooled to solidify the joining member. However, according to this method, the temperature of the entire package 101 increases, so that solder cannot be used for mounting electronic circuit components mounted inside the small recesses 104a, and mounting costs increase.

  Therefore, in this embodiment, as shown in FIG. 6, only the joint of the periphery of the lid 103 with the end face of the wall 102W of the package main body 102 is heated by the laser LZ, so that the package main body 102 is heated. The lid 103 is sealed and joined. In this embodiment, a low-melting-point material, in this example, low-melting-point glass, is used as the joining member 105 provided between the end face of the wall 102W of the package body 102 and the lid 103.

  Furthermore, in this embodiment, the heat dissipation via 110 for radiating heat by the laser LZ is provided in the wall portion 102W of the package body 102, and the conductor is filled in the via penetrating at least one of the plurality of LTCC substrates. It is embedded and provided. In this example, the heat radiating vias 110 are provided so as to penetrate all the layers of the LTCC of the plurality of layers constituting the wall 102W, and to expose the end to the end face of the wall 102W of the package body 102 to facilitate heat radiation. ing.

  The heat dissipation via 110 is formed by charging a conductor having a high heat conductivity higher than the heat conductivity of the ceramic material (LTCC substrate) forming the package body 102 and having good heat dissipation characteristics into the via. In this example, the via is filled with a material having a thermal conductivity of 4 W / mk or more, which is twice the thermal conductivity of the LTCC substrate, such as silver, for example. As shown in FIG. 1B, a plurality of the heat radiation vias 110 are provided by being embedded in the wall portion 102W of the package body 102 at predetermined intervals.

  When the lid 103 is sealed to the package body 102, in this example, as shown in FIG. 6, the laser LZ is applied along the periphery of the lid 103 from a direction perpendicular to the lid 103. And irradiate it to scan. Then, the joining member 105 made of low-melting glass between the lid 103 and the end face of the wall 102W of the package body 102 melts, and the lid 103 and the end face of the wall 102W of the package body 102 are joined. Become. Thereafter, when the laser LZ irradiation is stopped, the joining portion is cooled, the low-melting glass is solidified, and the lid 103 and the package main body 102 are joined to form the package 101 having a sealed structure.

  In this case, the wall portion 102W of the package body 102 is heated by the irradiation of the laser LZ. However, the heating is local, the bonding member 105 is made of low melting point glass, Due to the presence, the wall portion 102W of the package body 102 is efficiently radiated heat, so that even if solder is used for electrical connection between electronic circuit components housed in the small recesses 104a of the package body 102, The temperature does not reach a high temperature at which the solder melts out, and no failure occurs in the electrical connection between the components.

  As shown in FIG. 1 (B), the wireless sensor terminal 100 of this embodiment is arranged such that the bottom side of the package body 102 is more perpendicular to the wall 102W than the wall 102W of the package body 102. A flange 102F is formed so as to protrude. Through holes 102Fa, 102Fb, 102Fc, 102Fd for attachment are formed in the flange portion 102F. For example, through the through holes 102Fa, 102Fb, 102Fc, 102Fd and through holes formed in the attachment target portion, , A ceramic bolt can be penetrated and fixed with a ceramic nut.

  When a through hole cannot be formed in the mounting target portion, the bottom surface side of the package 101 is bonded with an adhesive to an object to be detected by the vibration sensor 212, for example, a bridge, a tunnel accessory, or a road accessory. However, since the area of the bonding portion and the joining portion with the object to which the wireless sensor terminal 100 is attached is increased by the amount of the flange portion 102F, the wireless sensor terminal 100 can be more firmly adhered and fixed to the object. I have to.

[Effect on Sealed Structure of Wireless Sensor Terminal of Embodiment]
As described above, according to the wireless sensor terminal 100 of this embodiment, the lid 103 made of the translucent ceramic is attached to the package body 102 formed by stacking the LTCC substrates, and the bonding member made of the low-melting glass. The package 101 can be made highly airtight by being sealed and bonded by 105. In this case, the wireless sensor terminal 100 according to the present embodiment accommodates sensors such as the vibration sensor 212 and electronic components such as the power transmission control circuit 201 and the wireless transmission circuit 216 and the processing control circuit 211 inside the package 101. Since the sensor data transmission antenna 310 is housed in the wall 102W, a so-called all-in-one package configuration can be obtained. Therefore, it is possible to realize a light-weight wireless sensor terminal that is robust enough to withstand an external impact.

  Since the solar cell module 202 is housed in the concave portion 104 of the package body 102, the solar cell module 202 does not cover the end surface of the wall 102W of the package body 102. Therefore, the sensor data transmission antenna 310 embedded in the wall portion 102W of the package body 102 can transmit and receive radio waves without being disturbed by the solar cell module 202.

  In the wireless sensor terminal 100 of this embodiment, the package 101 is entirely made of a ceramic material without using a metal part that hinders transmission / reception of radio waves, and the wall of the package body 102 in which the sensor data transmission antenna 310 is embedded. Since the unit 102W is formed of an LTCC substrate that can use a low-resistance conductor having good high-frequency characteristics, the unit 102W is configured so as to have reliability and sensitivity of the entire wireless sensor terminal 100 and stable antenna propagation characteristics. be able to.

  In addition, since the sensor data transmission antenna 310 has a non-directional configuration in which radio waves are radiated uniformly in all directions, the wireless sensor terminal 100 can be easily installed regardless of its position or direction. There is an effect that can be.

  Further, since the wireless sensor terminal 100 of this embodiment has a configuration in which the package 101 is entirely made of ceramic, other problems when the package is made of metal can be avoided. That is, for example, problems such as deterioration of durability due to rust on the metal housing, problems of shielding radio waves and light by the metal housing, damage of electronic components due to eddy current flowing into the package due to lightning strike, etc. This does not occur in the wireless sensor terminal 100 having the all-in-package configuration made of ceramic according to the embodiment.

  Further, in the wireless sensor terminal 100 of this embodiment, since the electrical connection terminals and the like are not exposed to the outside from the package 101, the high airtightness of the package 101 can be easily maintained, and the moisture permeation can be prevented. There is also an effect that it can be prevented.

  In the above-described embodiment, the electronic components arranged in the small recesses 104a of the package main body 102 are covered with the filling material so that the air layer does not come into contact with the electronic components. No deterioration due to In addition, since the filling material is made of a material having good heat radiation characteristics, heat generated from the electronic components is also radiated well, and a stable operation is ensured while realizing a long life as the wireless sensor terminal 100. There is also an effect that can be done.

  Therefore, the wireless sensor terminal 100 of this embodiment can be installed due to its high airtightness even under a high temperature, a low temperature, a high salt content environment, or a high concentration gas.

  In addition, in the wireless sensor terminal 100 of the above-described embodiment, not only the solar cell module 202 is used as the independent power supply, but also another independent power supply, and in the above-described embodiment, the vibration power generation element 203 is also used. Therefore, it can be used even in an installation place where the time for receiving light is short. Moreover, since the wireless sensor terminal 100 of the above-described embodiment includes the power storage element including the power storage capacitor 204, the surplus power of the solar cell module 202 and the vibration power generation element 203, which are independent power sources, is stored. Even when a power supply voltage cannot be obtained from these independent power supplies, there is an effect that the power can be driven by using the power stored in the power storage element.

  In addition, the sealing of the lid 103 to the package body 102 of the package 101 of the wireless sensor terminal 100 of the above-described embodiment is performed by using a joining member made of low-melting glass and by local heating using a laser. In addition, it is possible to suppress an increase in temperature inside the package body 102, and it is possible to use solder for electrical connection of electronic components arranged inside the package body 102. Further, in this embodiment, since the heat radiation via 110 is provided in the wall portion 102W of the package main body 102, a rise in the temperature inside the package main body 102 can be suppressed more reliably.

  Next, the configuration of the power-on control circuit 206, the power-off control circuit 207, the RFID circuit 217, the data demodulation circuit 218, and the power transmission control circuit 219 as specific circuits connected to the antennas 301 to 305 and an example of the processing operation thereof explain.

[About power-on control circuit 206 and power-off control circuit 207 connected to antennas 301 and 302]
FIG. 7 is a diagram for describing a detailed configuration example of a circuit portion including a switch circuit 205, a power-on control circuit 206, and a power-off control circuit 207 as an example of a specific circuit. In this example, the switch circuit 205 has a configuration of a switch circuit having a self-holding function including a PNP transistor 2051 and an NPN transistor 2052.

  In this example, the collector of the transistor 2051 is connected to the base of the transistor 2052, and the collector of the transistor 2052 is connected to the base of the transistor 2051. The storage voltage of the storage capacitor 204 made of a lithium ion capacitor (LiC) is applied to the emitter of the transistor 2051, and the power supply voltage Vcc is output from the emitter of the transistor 2052.

  A connection point between the collector of the transistor 2051 and the base of the transistor 2052 is connected to the power-on control circuit 206 and the power-off control circuit 207, and the switch circuit 205 is turned on by the power-on control circuit 206. The switch circuit 205 is controlled so as to be held in the self-state, and is controlled so as to be turned off by the power-off control circuit 207.

  The power-on control circuit 206 includes a band-pass filter 2061, a rectifier circuit 2062, a capacitor 2063, a diode 2064, and a power supply circuit 2065. The band pass filter 2061 is connected to the antenna 301 composed of the induction coil 301a, and passes a frequency component of 890 kHz to 930 kHz in a signal received by the antenna 301. The rectifier circuit 2062 rectifies the AC signal that has passed through the bandpass filter 2061, and charges the capacitor 2063 with the rectified current.

  Then, a current corresponding to the voltage stored in the capacitor 2063 is supplied as an ON control signal of the switch circuit 205 to a connection point between the collector of the transistor 2051 and the base of the transistor 2052, which constitute the switch circuit 205, through the diode 2064. . Further, in this embodiment, a current corresponding to the voltage stored in the capacitor 2063 is supplied to each circuit unit such as the processing control circuit 211 of the signal processing circuit system 210 via the power supply circuit 2065. In this example, the power supply circuit 2065 includes a backflow prevention diode.

  As described above, the power supply control circuit 201 controls whether to operate the power supply control process based on a command based on the control signal from the process control circuit 211. For this reason, when there is no generated voltage output from the solar cell module 202 or the vibration power generating element 203, and when the storage capacitor 204 is not charged to a predetermined value or more, the processing control circuit 211 does not operate. The circuit 201 may not operate. As described above, the power supply circuit 2065 turns on the switch circuit 205 when there is no generated voltage output from the solar cell module 202 or the vibration power generation element 203 and the storage capacitor 204 is not charged to a predetermined value or more. This is to ensure that the processing control circuit 211 operates reliably and the power supply control circuit 201 can be brought into the operating state.

  The power-off control circuit 207 includes a band-pass filter 2071, a rectifier circuit 2072, a capacitor 2073, a diode 2074, and a transistor 2075. The band-pass filter 2071 is connected to the antenna 302 including the induction coil 302a, and passes a frequency component of 100 kHz to 130 kHz in a signal received by the antenna 302. The rectifier circuit 2072 rectifies the AC signal that has passed through the bandpass filter 2071 and charges the capacitor 2073 with the rectified current.

  Then, a current corresponding to the voltage stored in the capacitor 2073 is supplied to the base of the transistor 2075 through the diode 2074. The collector of the transistor 2075 is connected to the connection point between the collector of the transistor 2051 forming the switch circuit 205 and the base of the transistor 2052, and the emitter is grounded.

  In this embodiment, a power-on signal transmission device 401 for transmitting a power-on signal from outside the package 101 to the wireless sensor terminal 100 is provided, and a power supply for transmitting a power-off signal from outside the package 101 is provided. An off signal transmitting device 402 is provided. In this embodiment, the power-on signal transmitting device 401 is a device that transmits, for example, an AC signal Pon having a frequency of 890 kHz to 930 kHz from an antenna 401a including an induction coil. The power-off signal transmitting device 402 is a device that transmits, for example, an AC signal Poff of 100 kHz to 130 kHz from the antenna 402a.

  The switch circuit 205 in the wireless sensor terminal 100 having the above structure remains off unless a current is supplied to the base of the transistor 2052. Therefore, in a state immediately after the wireless sensor terminal 100 is manufactured, the switch circuit 205 is turned off, and the power stored in the storage capacitor 204 is not consumed by the signal processing circuit system 210, and the storage capacitor 204 is not consumed. Is prevented from deteriorating.

  In this state, from outside the package 101, the power-on signal sending device 401 is moved so that the antenna 401a including the induction coil approaches the antenna 301 including the induction coil 301a with the above-described mark as a target. Then, the induction coil 301a and the induction coil constituting the antenna 401a are electromagnetically coupled, and the antenna 301 receives the AC signal Pon from the power-on signal transmission device 401.

  The AC signal Pon received by the antenna 301 is supplied to the rectifier circuit 2062 through the band-pass filter 2061 in the power-on control circuit 206, and the capacitor 2063 is charged. When the voltage (accumulated voltage) across the capacitor 2063 becomes equal to or more than a predetermined value, a current flows through the diode 2064 to the base of the transistor 2052 of the switch circuit 205, and the transistor 2052 is turned on. Accordingly, the transistor 2051 is also turned on, and the base current of the transistor 2052 is constantly supplied from the storage capacitor 204 to the base of the transistor 2052 via the transistor 2051, and the switch circuit 205 is turned on. .

  That is, after that, when the power-on signal transmitting device 401 is moved away from the package 101 of the wireless sensor terminal 100, the power-on control circuit 206 cannot receive the signal from the power-on signal transmitting device 401. The base current from transistor to transistor 2052 disappears. However, in the switch circuit 205, the base current is continuously supplied to the transistor 2052 through the transistor 2051, so that the switch circuit 205 is kept on.

  In this way, once the switch circuit 205 is turned on, the switch circuit 205 holds the on state, and supplies power from the power control circuit 201 to each part of the signal processing circuit system 210 through the switch circuit 205 via the storage capacitor 204. The state is such that the voltage Vcc is continuously supplied.

  Next, in order to turn off the switch circuit 205 which has been turned on, the antenna 402a composed of an induction coil of the power-off signal transmitting device 402 is configured from outside the package 101 by configuring the antenna 302 with the above-described mark as a target. Of the induction coil 302a to be approached. Then, the antenna 302 and the antenna 402a are electromagnetically coupled, and the antenna 302 receives the AC signal Poff from the power-off signal transmitting device 402.

  The AC signal Poff received by the antenna 302 is supplied to the rectifier circuit 2072 through the band-pass filter 2071 in the power-off control circuit 207, and the capacitor 2073 is charged. When the voltage (accumulated voltage) across the capacitor 2073 exceeds a predetermined value, a current flows through the diode 2074 to the base of the transistor 2075, and the transistor 2075 is turned on. Accordingly, the base of the transistor 2052 of the switch circuit 205 is grounded, and the base current does not flow through the transistor 2052, so that the transistor 2052 is turned off, and accordingly, the transistor 2051 is also turned off. Therefore, switch circuit 205 is turned off, and supply of power supply voltage Vcc from power storage capacitor 204 to signal processing circuit system 210 is cut off.

  After that, even if the power-off signal transmitting device 402 is moved away from the package 101 of the wireless sensor terminal 100, no base current flows through the transistor 2052 of the switch circuit 205, so that the switch circuit 205 remains off.

  As described above, according to the wireless sensor terminal 100 of the present embodiment, the steady-state power supply between the power storage capacitor 204 and the signal processing circuit 210 serving as a load circuit between the power storage capacitor 204 and the signal processing circuit system 210 as a load circuit. Is provided with a switch circuit 205 that is turned off, so that when the wireless sensor terminal 100 is not used (during stock), the stored power of the storage capacitor 204 is wastefully consumed by the signal processing circuit system 210. There is no. For this reason, a measure for preventing a situation in which the storage capacitor 204 becomes equal to or lower than a predetermined voltage (discharge end voltage) is also facilitated.

  For example, when disposing the storage capacitor 204 in the package 101 of the wireless sensor terminal 100, the storage capacitor 204 is stored in advance in anticipation of the stock time (stock time) of the wireless sensor terminal 100. By doing so, it is possible to prevent a situation in which the storage capacitor 204 becomes equal to or lower than a predetermined voltage (discharge end voltage). Further, when the scheduled stock time elapses, the self-standing power generation element of the wireless sensor terminal 100 can generate power and manage the power storage capacitor 204 so as to store power, which facilitates inventory management. Becomes

  In the above-described embodiment, the power supply off control circuit 207 is provided and the power supply off signal transmission device 402 is prepared so that the switch circuit 205 in the on state can be turned off from outside the wireless sensor terminal 100. I made it. However, in the wireless sensor terminal 100 of this embodiment, it is only necessary to turn on the switch circuit 205 which has been turned off and turn on the power to the signal processing circuit system 210. Therefore, the power supply off signal transmission device 402 is also prepared. It is not mandatory to do so. However, when the power-off control circuit 207 is configured to be able to turn off the switch circuit 205 that has been on when receiving an AC signal from the power-off signal transmission device 402, There is an effect that the operation of the wireless sensor terminal 100 can be temporarily stopped and then restarted.

[Configuration Example and Operation Example of RFID Circuit 217]
FIG. 8 is a block diagram showing an example of the configuration of the RFID circuit 217 of this embodiment. The RFID circuit 217 of this example includes a controller 2171 including a microprocessor, a memory 217M, an analog front-end circuit 2172, an RF matching circuit 2173, and an I ² C interface 2174.

  Then, an induction coil 303a constituting the antenna 303 is connected to the RF matching circuit 2173. The RF matching circuit 2173 sends a signal received through the antenna 303 to the analog front end circuit 2172. The analog front-end circuit 2172 converts a signal obtained from the RF matching circuit 2173 into a digital signal and supplies the digital signal to the controller 2171.

The controller 2171 is connected to the memory 217M and the I ² C interface 2174. As described above, in this embodiment, information on the diagnosis result of the failure / deterioration from the failure / deterioration diagnosis sensor 214 is sent from the processing control circuit 211 to the RFID circuit 217 via the I ² C bus. The controller 2171 acquires the information of the failure / deterioration diagnosis result from the processing control circuit 211 through the I ² C interface 2174, and accumulates it in the memory 217M together with the time information as the history information of the failure / deterioration diagnosis.

  When the controller 2171 receives, from the analog front-end circuit 2172, a trigger signal for requesting acquisition of history information of failure / deterioration diagnosis from an external device, the failure / deterioration diagnosis stored in the memory 217M is received. The history information is sent to an external device through the analog front-end circuit 2172, the RF matching circuit 2173, and the antenna 303.

  Although not shown in FIG. 8, in this example, a device for acquiring history information of failure / deterioration diagnosis is prepared as an external device. This acquisition device includes, as an antenna, an induction coil that electromagnetically couples with an induction coil 303a that constitutes the antenna 303, and sends a trigger signal for a request for acquiring history information of failure / deterioration diagnosis, thereby performing failure / deterioration diagnosis. It has a function of acquiring and retaining history information.

  FIG. 9 is a flowchart illustrating an example of the flow of a process performed by the controller 2171. That is, the controller 2171 receives and detects a trigger signal from an external device, that is, a device for acquiring history information of failure / deterioration diagnosis, via the antenna 303, the RF matching circuit 2173, and the analog front-end circuit 2172. Is determined (step S101).

When it is determined in step S101 that the trigger signal has not been detected, the controller 2171 determines whether or not information on a failure / deterioration diagnosis result has been received from the processing control circuit 211 via the I ² C interface 2174. (Step S102). If it is determined in step S102 that the information of the failure / deterioration diagnosis result from the processing control circuit 211 has not been received, the controller 2171 returns the process to step S101, and repeats the processes from step S101. .

  If it is determined in step S102 that the information on the failure / deterioration diagnosis result has been received from the processing control circuit 211, the controller 2171 stores the received information on the failure / deterioration diagnosis result in the memory 217M and accumulates the information. (Step S103). After step S103, the controller 2171 returns the process to step S101, and repeats the processes from step S101.

  If it is determined in step S101 that the trigger signal has been detected, the controller 2171 reads out all the history information of the failure / deterioration diagnosis results accumulated in the memory 217M up to that point, and reads the analog front end circuit 2172. The information is sent to an external device, that is, a device for acquiring history information of failure / deterioration diagnosis through the RF matching circuit 2173 and the antenna 303 (step S104).

  Thus, according to the wireless sensor terminal 100 of the present embodiment, the antenna (induction coil of the acquisition device of the history information of the diagnosis of the failure / deterioration is provided for the package 101 having the sealed configuration in which the external terminal does not exist. )), And electromagnetically coupled to the induction coil 303a, it is possible to easily obtain the history information of the failure / deterioration diagnosis of the internal circuit of the wireless sensor terminal 100. Then, by analyzing the failure / deterioration diagnosis history information obtained by the failure / deterioration diagnosis history acquisition device, it is possible to check whether a failure or deterioration has occurred in the wireless sensor terminal 100. This is very convenient.

[Power supply to external device and acquisition and demodulation of external data]
In the wireless sensor terminal 100 of this embodiment, by using the antenna 305 and the power transmission control circuit 219, and the antenna 304 and the data demodulation circuit 218, power is supplied to the sensor device existing outside the package 101 of the wireless sensor terminal 100. It can be configured to supply a voltage, receive sensor data from the external sensor device, and wirelessly transmit the sensor data through its own sensor data transmission antenna 310.

  FIG. 10 illustrates a case where the wireless sensor terminal 100 supplies a power supply voltage to the sensor device 411 existing outside the package 101, receives sensor data from the sensor device 411, and transmits the sensor data from the sensor data transmission antenna 310. 1 is a diagram showing an example of a system configuration of FIG. As shown in FIG. 10, in this example, a power reception adapter 412 and a data transmission adapter 413 are provided between the external sensor device 411 and the wireless sensor terminal 100.

  The power receiving adapter 412 is provided with a power receiving unit 4121 and, in this example, an antenna 4122 including an induction coil 4122a. The data transmission adapter 413 includes a data modulation circuit 4131 and, in this example, an antenna 4132 including an induction coil 4132a. The data demodulation circuit 218 of the wireless sensor terminal 100 demodulates the sensor data modulated by the data transmission adapter 413 data modulation circuit 4131.

  Then, the power receiving unit 4121 of the power receiving adapter 412 is connected to the power supply terminal VP of the sensor device 411. The input terminal of the data modulation circuit 4131 of the data transmission adapter 413 is connected to the sensor data output terminal DA of the sensor device 411.

  In this embodiment, the power transmission control circuit 219 of the wireless sensor terminal 100 includes a power transmission unit 2191 to which an induction coil 305a constituting an antenna 305 is connected as shown in FIG. The switch circuit 2192 is provided between the power supply unit 2191 and the power supply unit 2191. The switch circuit 2192 is turned on / off by a switch control signal from the power supply control circuit 201. That is, the power supply control circuit 201 monitors the storage voltage of the storage capacitor 204, and only when the storage voltage of the storage capacitor 204 is a voltage that can supply power to the outside. , So that the switch circuit 2192 is turned on.

  Then, when the antenna 4122 of the power receiving adapter 412 is brought close to the antenna 305 of the wireless sensor terminal 100 with the above-described mark as an eye, the induction coil 305a and the induction coil 4122a are electromagnetically coupled, and the switch circuit 2192 is turned on. If, the power supply voltage according to the power supply voltage Vcc is transmitted from the power transmission unit 2191 to the power reception unit 4121 and supplied to the power supply terminal VP of the external sensor device 411.

  In this case, the power transmission by the power transmission unit 2191 and the power reception unit 4121 is performed by a known method such as magnetic resonance power transmission, and the detailed configuration and operation are omitted here.

  The sensor device 411 is driven by receiving the supply of the power supply voltage from the power receiving adapter 412 and supplies sensor data as a result of detection by a built-in sensor to the data transmitting adapter 413 through the sensor data output terminal DA. .

  Then, when the antenna 4132 of the data transmission adapter 413 is brought close to the antenna 304 of the wireless sensor terminal 100 with the above-described mark as an eye, the induction coil 305a and the induction coil 4122a are electromagnetically coupled. The data modulation circuit 4131 of the data transmission adapter 413 performs predetermined modulation on the sensor data received from the sensor device 411, and transmits the modulated data to the wireless sensor terminal 100 via the antenna 4132.

  In the wireless sensor terminal 100, when the external sensor data is received by the antenna 304, the sensor data 2 is demodulated by the data demodulation circuit 218 and supplied to the processing control circuit 211. The processing control circuit 211 executes a processing operation example as shown in the flowchart of FIG. 11 with respect to the reception of the sensor data from the outside.

That is, the processing control circuit 211 monitors the reception of the demodulated sensor data from the data demodulation circuit 218 (step S201), and when it determines that the demodulated sensor data has not been received, the built-in vibration sensor 212 A normal processing routine for transmitting sensor data from the temperature sensor 213 through the antenna 310 and transferring information on a failure / deterioration diagnosis result obtained from the failure / deterioration diagnosis sensor 214 to the RFID circuit 217 via the I ² C bus. Is executed (step S202). After step S202, the process control circuit 211 returns the process to step S201, and repeats the processes after step S201.

  If it is determined in step S201 that the demodulated sensor data from the data demodulation circuit 218 has been received, the processing control circuit 211 sends the received sensor data to the wireless transmission circuit 216 via the memory 215, Radio transmission is performed outside through the transmission antenna 310 (step S203). After step S203, the process control circuit 211 returns the process to step S201, and repeats the processes after step S201.

  In the configuration of FIG. 10, the external sensor device 411 may have a configuration in which the power receiving adapter 412 and the data transmitting adapter 413 are incorporated.

  As described above, according to the wireless sensor terminal 100 of the present embodiment, the antenna 4122 (the induction coil 4122a) of the power receiving adapter 412 is connected to the package 101 having a sealed configuration without external terminals. The power supply voltage can be provided to an external sensor device connected to the power receiving adapter 412 by electromagnetic coupling with the induction coil 305 a constituting the antenna 305 in close proximity. In addition, the antenna 4132 (the induction coil 4132a) of the data transmission adapter 413 is brought close to the package 101 having a sealed configuration in which no external terminal is present, and the induction coil 304a configuring the antenna 304 of the wireless sensor terminal 100 is brought close. By electromagnetically coupling to the data transmission adapter 413, the wireless sensor terminal 100 of this embodiment can wirelessly transmit sensor data from an external sensor device connected to the data transmission adapter 413 to the outside.

  In particular, when the wireless sensor terminal 100 is configured to supply power to the external sensor device 411 and wirelessly transmit the sensor data acquired from the sensor device 411 as in the example of FIG. Such effects can be obtained.

  That is, when it is necessary to detect a detection target attribute that cannot be detected by the sensor included in the wireless sensor terminal 100, the detection target attribute of the sensor of the external sensor device 411 is set as the detection target attribute that requires the detection. What is necessary is just to comprise so that it may electromagnetically couple with the wireless sensor terminal 100 via the power reception adapter 412 and the data transmission adapter 413.

  In this case, the external sensor device 411 does not need a self-contained power supply only by providing the power supply terminal VP, and does not require a sensor data transmission antenna or a wireless transmission circuit, so that a simple configuration can be achieved.

  When the configuration of the external sensor device 411 is configured to include the power receiving adapter 412 and the data transmitting adapter 413, the external sensor device 411 is also similar to the wireless sensor terminal 100 as a whole. Of a closed type package.

  Note that the example of FIG. 10 particularly shows a configuration example in which the wireless sensor terminal 100 acquires sensor data from the external sensor device 411 and wirelessly transmits the power while supplying power to the external sensor device 411. However, it is not limited to such an example. That is, an external device that receives only the supply of the power supply voltage from the wireless sensor terminal 100 may be connected to the power receiving adapter 412, or such an external device includes the power receiving adapter 412. You may do so.

  The data transmission adapter 413 may be connected to an external device that generates predetermined data that is not limited to sensor data, or such an external device may include the data transmission adapter 413. You may. In that case, the external device itself may be provided with a power supply. In that case, it is needless to say that the external device does not need to be supplied with the power supply voltage from the wireless sensor terminal 100.

[Other Embodiments and Modifications]
In the above-described embodiment, the induction coils constituting the antennas 301 to 305 are embedded in the wall portion 102W of the package main body 102. However, as shown in FIG. On the wall surface (the inner wall surface of the wall portion 102W), for example, a conductor such as copper foil may be formed as a loop coil pattern 421, 422 of one or more turns.

  In addition, although the antennas 301 to 305 have the configuration of the induction coil in the above-described embodiment, it is needless to say that the antennas 301 to 305 may be configured of a rod-shaped conductor instead of the induction coil.

  In the above-described embodiment, the antennas 301 to 305 are provided on the wall 102W of the substantially rectangular parallelepiped package 101. It may be provided inside.

  In the above-described embodiment, the wireless sensor terminal 100 is provided with a plurality of antennas, such as the antennas 301 to 305 and the corresponding specific circuits. However, one antenna and the antenna connected thereto are provided. Needless to say, a configuration having only one specific circuit may be employed.

  Further, in the above-described embodiment, the external shape of the package of the wireless sensor terminal is a rectangular parallelepiped shape. However, the external shape of the package of the wireless sensor terminal of the present invention is not limited to this. The shape may be a pyramid, a cone, a dome, a sphere, a hemisphere, or the like.

  In the above-described embodiment, the wireless sensor terminal 100 is dedicated to the transmission of the sensor data. Alternatively, a configuration may be adopted in which a signal from the outside can be received through the antenna 310.

  100: wireless sensor terminal, 101: package, 102: package body, 102W: wall of package body, 103: lid, 104: recess, 202: solar cell module, 203: vibration power generation element, 204: capacitor for power storage, 205 switch circuit, 206 power-on control circuit, 207 power-off control circuit, 211 processing control circuit, 212 vibration sensor, 213 temperature sensor, 216 wireless transmission circuit, 217 RFID circuit, 218 data demodulation Circuit, 219: Power transmission control circuit, 310: Sensor data transmission antenna (first antenna), 301 to 305: Antenna (second antenna), 301a to 305a: Induction coil, 401: Power-on signal transmission device, 402 ... Power off signal transmission device, 411 ... Sensor device

Claims (12)

At least, a sensor, a signal processing circuit system including a wireless transmission circuit that wirelessly transmits information detected by the sensor ,
A first antenna connected to the wireless transmission circuit;
A power generation unit for generating power, a power storage element storing a storage voltage higher than a specified voltage , and receiving the power generated by the power generation unit, controlling the storage voltage so as not to be lower than the specified voltage. A power supply system that includes a power supply control circuit that generates a power supply voltage while storing power in the element ;
A switch circuit that is provided in a power supply path between the signal processing circuit system and the power supply system, has an initial state of OFF, and self-holds an ON state when switched on.
A power-on control circuit for turning on the switch circuit;
A second antenna connected to the power-on control circuit;
A wireless sensor terminal provided in a hermetically sealed package in which the lid is hermetically sealed,
The wireless sensor terminal , wherein the power-on control circuit switches on the switch circuit based on a signal received from the outside through the second antenna . The power supply control circuit is configured to control whether to operate a power supply control process based on a command by a control signal from a processing control circuit included in the signal processing circuit system,
The power-on control circuit supplies a voltage that enables the processing control circuit to drive the processing control circuit, regardless of a value of a power supply voltage supplied to the signal processing circuit system when the switch circuit is turned on. The wireless sensor terminal according to claim 1, further comprising a power supply circuit that supplies power . It said signal processing circuit system is provided with a storage unit for collecting and storing information for fault or degradation diagnosis of the circuit components including the said sensors and said wireless transmission circuit before Symbol sealed package, the sealed A circuit that transmits the information stored in the storage unit to the outside through the second antenna based on reception of a signal from outside through a third antenna provided in the package. The wireless sensor terminal according to claim 1 or 2 , wherein Wherein the signal processing circuitry, to the external device of the hermetic package, according to claim 1, the power supply voltage, characterized in that it comprises a circuit for supplying through a fourth antenna provided in the hermetic package The wireless sensor terminal according to claim 3 . The signal processing circuit system receives data from a device outside the sealed package through a fifth antenna provided in the sealed package, and transmits the received data to the outside through the first antenna. The wireless sensor terminal according to any one of claims 1 to 4, further comprising a circuit that performs the operation. The wireless sensor terminal according to claim 5, wherein the external device includes a sensor, and data from the external device is sensor data detected by the sensor. The hermetic package includes a concave portion surrounded by a wall portion, and the power generation portion, the power storage element, the power supply control circuit, and the wireless transmission circuit are arranged in the concave portion, and inside the wall portion. The wireless sensor terminal according to any one of claims 1 to 6, wherein the first antenna and the second antenna are embedded and provided. The hermetic package is configured as a laminate of a plurality of ceramic layers,
The first antenna and the second antenna are configured by a conductor filled in a via penetrating at least one of the plurality of ceramic layers,
An electrical connection between the wireless transmission circuit and the first antenna and an electrical connection between the power-on control circuit and the second antenna are provided between the stacked ceramic layers. The wireless sensor terminal according to any one of claims 1 to 7, wherein the wireless sensor terminal is performed through a conductor. The wireless sensor terminal according to any one of claims 1 to 8, wherein the power generation unit generates power by receiving power generation energy depending on an environment. The wireless sensor terminal according to claim 9, wherein the power generation unit includes a solar cell module. The wireless sensor terminal according to claim 9, wherein the power generation unit includes a vibration power generation element. The wireless sensor terminal according to claim 1, wherein the second antenna includes an induction coil.

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