Communication device, and power source device

Abstract

A communication device 100 according to the present invention is provided in a space comprising a hole configured from a side wall 11 and / or a bottom, and a lid 12 covering the hole, and is provided with: a plate member 101 for acquiring heat of the lid; a heat moving member 102 which is connected to the plate member to move the heat of the lid; a thermoelectric electricity generating unit 103 having a first joining point which is connected to the heat moving member, and a second joining point which is connected to the side wall or the bottom, or to a liquid present in the hole; and a communication unit 104 which performs communication by means of electric power generated by the thermoelectric electricity generating unit.

Description

Communication equipment and power supply equipment CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Patent Application No. 2021-056242, filed on March 29, 2021, the contents of which are incorporated herein by reference.

[0002] The present invention relates to a communication device to be installed in a manhole, a handhole, or the like, and a power supply device that can be mounted on the communication device.

[0003] There are devices that detect abnormalities by acquiring environmental information about manholes and handholes. There is also known technology for collecting, storing, and utilizing various data by transmitting data collected in remote locations using low-power, long-distance wireless communication methods such as LPWA (Low Power Wide Area).

[0004] JP 2006-233436 A JP 2015-12431 A

[0005] When environmental information about manholes and handholes is detected by sensors and transmitted wirelessly, a power source is required to operate the communication device. Manholes and handholes are usually covered with metal covers, which prevent sunlight from reaching them, making it difficult to generate power from sunlight. Furthermore, if primary batteries are used, they will need to be replaced periodically.

[0006] An object of the present invention is to realize a communication device that does not require battery replacement.

[0007] A communication device (100) according to one aspect of the present disclosure is a communication device installed in a space formed by a hole formed by a sidewall (11) and / or a bottom and a lid (12) covering the hole, and includes: a plate member (101) that "acquires" heat from the lid; a heat transfer member (102) connected to the plate member and transferring the heat from the lid; a thermoelectric power generation unit (103) having a first junction connected to the heat transfer member and a second junction connected to the sidewall, the bottom, or a liquid present in the hole; and a communication unit (104) that communicates using power generated by the thermoelectric power generation unit. Here, "heat" refers not only to the case where the temperature of the lid is higher than the temperature of the sidewall, but also to the case where heat transfers from the sidewall to the lid when the temperature of the lid is lower than the temperature of the sidewall, i.e., the case where negative heat transfers from the lid to the sidewall. Furthermore, "acquiring" refers to the transfer of heat to the plate member by transmission or conduction.

[0008] It should be noted that the claims and the numbers in parentheses attached to the constituent elements of the invention described in this section indicate the correspondence between the present invention and the embodiments described below, and are not intended to limit the present invention.

[0009] According to the present invention, a communication device that does not require battery replacement can be realized.

[0010] 1 is a side view of the communication device of this embodiment; 2 is a front view of the communication device of this embodiment; 3 is an explanatory diagram illustrating the installation state of the plate member of the communication device of this embodiment; 4 is an explanatory diagram illustrating the daytime operation of the communication device of this embodiment; 5 is an explanatory diagram illustrating the nighttime operation of the communication device of this embodiment;

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0012] The present invention refers to the invention described in the claims and is not limited to the following embodiments. Furthermore, at least the words in quotation marks refer to the words described in the claims and are not limited to the following embodiments.

[0013] The configurations and methods recited in the dependent claims are optional configurations and methods in the inventions recited in the independent claims. The configurations and methods of the embodiments corresponding to the configurations and methods recited in the dependent claims, as well as the configurations and methods recited only in the embodiments without being recited in the claims, are optional configurations and methods in the present invention. The configurations and methods recited in the embodiments when the recitation of the claims is broader than the recitation of the embodiments are also optional configurations and methods in the present invention, in the sense that they are examples of the configurations and methods of the present invention. In either case, by being recited in the independent claims, they become essential configurations and methods of the present invention.

[0014] The effects described in the embodiments are effects obtained when the configurations of the embodiments are provided as examples of the present invention, and are not necessarily effects that the present invention has.

[0015] When there are multiple embodiments, the configurations disclosed in each embodiment are not limited to each embodiment, but can be combined across the embodiments. For example, a configuration disclosed in one embodiment may be combined with another embodiment. Also, configurations disclosed in multiple embodiments may be collected and combined.

[0016] The problems described in this disclosure are not publicly known problems, but have been independently discovered by the inventors, and together with the configuration and method of the present invention, these facts affirm the inventive step of the invention.

[0017] (Embodiment 1) 1. Location where the communication device and power supply device of this embodiment are installed Vertical holes are provided in the ground to allow workers to access underground sewers, culverts, water supply systems, buried electrical and communication cables, and buried gas pipes from above ground for the purpose of managing them (for inspection, repair, cleaning, exhaust, etc.). Vertical holes are called manholes or handholes. Alternatively, gutters are provided on at least one side of a road to drain water that has accumulated on the road.

[0018] The manhole, handhole, and gutter (all of which correspond to "holes") are made up of a side wall 11. The gutter 11 is made of, for example, concrete or earth.

[0019] Furthermore, manholes, handholes, and drains are covered with circular or rectangular metal covers 12 to prevent people or objects from accidentally falling into them.

[0020] The communication device 100 and the power supply device 150 of this embodiment are provided in the space defined by the “hole” and the lid 12 .

[0021] 2. Configuration of the Communication Device and Power Supply Device The configuration of the communication device 100 and power supply device 150 of this embodiment will be described using Figures 1 and 2. Figure 1 is a side view of the communication device 100 of this embodiment, and Figure 2 is a front view of the communication device 100 as seen from direction A in Figure 1. The communication device 100 is made up of a plate member 101, a heat transfer member 102, a thermoelectric power generation unit 103, a communication unit 104, a secondary battery 105, and a primary battery 106.

[0022] The plate member 101 is a plate-shaped member, and is sandwiched between the rear surface of the lid 12 and the upper surface of the side wall 11 when the communication device 100 is installed in the space defined by the hole and the lid 12 .

[0023] The top surface of the plate member 101 contacts the back surface of the lid 12 and acquires heat from the lid 12. The plate member 101 is made of a metal with high thermal conductivity, such as iron (including alloys), copper (including alloys), or aluminum. Alternatively, thermally conductive plastic or ceramics can also be used.

[0024] An elastically deformable leaf spring may be used as the plate member 101. For example, as shown in Fig. 3(A), the portion of the plate member 101 that protrudes from the side wall 11 toward the hole is curved upward. When the lid 12 is placed over the hole, the curved portion is pressed by the lid 12 and elastically deforms, resulting in the back surface of the lid 12 constantly receiving stress from the plate member 101 as indicated by the arrows, as shown in Fig. 3(B). With this configuration, good contact between the plate member 101 and the lid 12 can be maintained.

[0025] 3C , when the plate member 101 is provided so as to be sandwiched between the rear surface of the lid 12 and the upper surface of the side wall 11, the end of the plate member 101 may be warped toward the side wall 11, thereby generating stress that presses the thermoelectric power generation unit 103 against the side surface of the side wall 11 via the heat transfer member 102. With this configuration, good contact between the thermoelectric power generation unit 103 and the side wall 11 can be maintained.

[0026] It is also possible to apply a heat insulating material to the underside of the plate member 101, i.e., the surface that contacts the upper surface of the side wall 11, or to sandwich a heat insulating material between the plate member 101 and the upper surface of the side wall 11. This configuration can prevent heat from the lid 12 from being transferred directly to the side wall 12 via the plate member 101. It is also possible for the plate member 101 to have a shape other than a plate. For example, it is sufficient if the plate member has a shape that can contact the back surface of the lid 12, and the "plate member" can be referred to as a lid contact member or can be read as a lid contact member.

[0027] According to the plate member 101 of this embodiment, a space is formed between the lid 12 and the side wall 11, which reduces the area of ​​direct contact between the lid 12 and the side wall 11, thereby preventing heat from the lid 12 from transferring directly to the side wall 11. Furthermore, according to the plate member 101 of this embodiment, a space is formed between the lid 12 and the side wall 11, which allows radio waves used by the communication unit 104 (described later) to leak from this space, thereby improving the quality of communication with an external base station device.

[0028] The heat transfer member 102 has one end connected to the plate member 101 and the other end connected to a first joint point of the thermoelectric generator 103 , thereby transferring heat from the lid 12 to the thermoelectric generator 103 .

[0029] The heat transfer member 102 may be a plate- or rod-shaped member made of a highly thermally conductive material such as copper, or a heat pipe. A heat pipe is a member that uses the principle or mechanism of transferring heat by using the movement of an internal working fluid. When a heat pipe is used, multiple heat pipes with a round cross section may be bundled together.

[0030] Furthermore, when installing the communication device 100, by configuring or installing the heat transfer member 102 in a manner that allows it to elastically deform, it is possible to generate stress that presses the thermoelectric power generation unit 103 against the side surface of the side wall 11, thereby maintaining good contact between the thermoelectric power generation unit 103 and the side wall 11. The heat transfer member 102 and the plate member 101 may be configured as a single member. In this case, the single member is the heat transfer member 102 and the plate member 101. The thermoelectric power generation unit 103, which will be described later, may also be directly connected to the plate member 101. In this case, the plate member 101 also serves as the function of the heat transfer member 102.

[0031] The thermoelectric power generation unit 103 generates thermoelectric power using the Seebeck effect, with a first junction connected to the heat transfer member 102 and a second junction connected to the side wall 11. The first junction and the second junction include a line or a surface.

[0032] The thermoelectric power generation unit 103 includes a thermoelectric power generation element 107 and thermally conductive adhesives 108 and 109. The thermoelectric power generation element 107 is a power generation element that utilizes the Seebeck effect, and is a power generation device that converts thermal energy into electrical energy by contacting one junction point with a high heat source and the other junction point with a low heat source to generate a potential difference. The thermoelectric power generation element 107 may be made of, for example, a bismuth-tellurium (Bi-Te)-based, lead-tellurium (Pb-Te)-based, or silicon-germanium (Si-Ge)-based material. The thermoelectric power generation element 107 may also be a skeleton type.

[0033] Both surfaces of the thermoelectric generating element 107 may be made of a material with high thermal conductivity, such as copper, aluminum (preferably after anodizing), stainless steel (e.g., SUS304), ceramics, or thermally conductive plastic.

[0034] Thermally conductive adhesives 108 and 109 are provided on each surface of the thermoelectric generating element 107. For example, alpha gel, silicone, or a metal-based adhesive can be used for the thermally conductive adhesives 108 and 109. The thermally conductive adhesive 108 forms a first connection point and is connected to the thermal transfer member 102. The thermally conductive adhesive 109 forms a second connection point and is connected to the side wall 11. In this embodiment, the second connection point is located above the side wall 11, but it may be located near the bottom of the hole. In this case, a thermal transfer member such as a heat pipe may be provided between the thermally conductive adhesive 109 and the side wall 11. In this case, the heat pipe also constitutes the thermoelectric generating unit 103.

[0035] In this embodiment, the thermoelectric power generation unit 103 is connected to the heat transfer member 102 and the side wall 11 via the thermally conductive adhesives 108 and 109, respectively, but the thermoelectric power generation element 107 may be directly connected to the heat transfer member 102 and the side wall 11, respectively, without using the thermally conductive adhesives 108 and 109. Note that instead of the thermally conductive adhesives 108 and 109, a thermally conductive material with no adhesive strength may be used.

[0036] The communication unit 104 communicates using the power generated by the thermoelectric power generation unit 103. The communication method of the communication unit 104 can be any wireless communication method. For example, in addition to wideband cellular communications known as 3G, 4G, and 5G, a low-power, long-distance wireless communication method (LPWA (Low Power Wide Area)) that consumes little power and enables long-distance communication can be used. The LPWA method is a communication method that mainly uses the 800 / 900 MHz band known as the sub-gigahertz band. Examples of such methods include eMTC (enhanced Machine Type Communication) proposed by the Third Generation Partnership Project (3GPP), NB-IoT (Narrow Band Internet of Things) optimized for smaller amounts of data communication, SIGFOX (registered trademark) developed by Sigfox, and LoRa (registered trademark) developed by Semtech, but are not limited to these. PARCA (registered trademark), which is characterized by broadcast-type two-way communication proposed by the applicant of the present application, can also be used. Alternatively, short-range wireless communication methods such as Wi-Fi (registered trademark), ZigBee (registered trademark), Bluetooth (registered trademark), Bluetooth Low Energy (BLE), FeliCa (registered trademark), NFC (Near Field Communication), and RFID can also be used.

[0037] The communication unit 104 may be configured to receive the power generated by the thermoelectric power generation unit 103 directly from the thermoelectric power generation unit 103, or may be configured to first store the power generated by the thermoelectric power generation unit 103 in the secondary battery 105 and then receive the power from the secondary battery 105.

[0038] Furthermore, the communication unit 104 may be configured to receive power from the primary battery 106. In particular, when the temperature difference between the lid 12 and the side wall 11 is smaller than a predetermined threshold, the thermoelectric power generation unit 103 does not supply sufficient power, causing a shortage of power stored in the secondary battery 105. Only in such a case may the communication unit 104 be configured to receive power from the primary battery 106 as a backup power source.

[0039] The communication unit 104 transmits an output signal of a sensor that acquires environmental information. For example, an input terminal of the sensor is provided in the communication device 100, and the sensor is connected to the input terminal, whereby the communication unit 104 transmits the output signal of the sensor.

[0040] The sensor can be any sensor that acquires the necessary environmental information. Examples include a temperature sensor that measures the temperature inside the manhole and a humidity sensor that measures the humidity inside the manhole. Other examples include a gas sensor that detects gas inside the manhole and an corrosion potential sensor (voltmeter or ammeter) that measures the corrosion potential of the piping inside the manhole.

[0041] The communication unit 104 may include an RF circuit, a power supply circuit, and a sensing circuit.

[0042] The antenna 110 is connected to the communication unit 104 and transmits an output signal output from the communication unit 104. An inverted-F board antenna or a whip antenna can be used as the antenna 110. It is desirable to provide the antenna 110 at a distance from the heat transfer member 102. This can increase the antenna sensitivity. The antenna 110 may also be earthed from the lid 12. This can increase the antenna sensitivity.

[0043] The power supply device 150 of this embodiment is composed of the plate member 101, the heat transfer member 102, and the thermoelectric power generation unit 103. The power supply device 150 may further include a secondary battery 105 and a primary battery 106.

[0044] 3. Operation of the Communication Device and the Power Supply Device The operation of the communication device 100 and the power supply device 150 of this embodiment will be described with reference to Figures 4 and 5. Figure 4 shows the situation during the day, and Figure 5 shows the situation at night.

[0045] 4, during the daytime, the temperature of the lid 12 rises due to radiant heat from the sun, so the temperature of the lid 12 is higher than that of the side wall 11. Therefore, heat is transferred to the side wall 11 via the plate member 101, the heat transfer member 102, and the thermoelectric power generation unit 103 in this order. The temperature difference (i.e., heat flux) between the lid 12 and the side wall 11 at this time causes the thermoelectric power generation unit 103 to generate electricity.

[0046] 5 , at night, the temperature of lid 12 drops due to a drop in the outside air temperature, so the temperature of side wall 11 is higher than that of lid 12. Therefore, heat is transferred to lid 12 via side wall 11, thermoelectric power generation unit 103, and heat transfer member 102 in this order. The temperature difference (i.e., heat flux) between lid 12 and side wall 11 at this time causes thermoelectric power generation unit 103 to generate electricity.

[0047] 4 and 5, however, the direction of the current generated by the thermoelectric power generation unit 103 is reversed, so the thermoelectric power generation unit 103 can be considered as an AC generator with a long period. Therefore, by providing the thermoelectric power generation unit 103 with a rectifier circuit (charge circuit) (not shown), AC can be converted to DC.

[0048] In the description of this embodiment, the state of Fig. 4 is assumed, but in the state of Fig. 5, the direction of heat transfer is interpreted as being reversed. Alternatively, in the state of Fig. 5, it is interpreted that negative heat transfers from the lid 12 to the side wall 11.

[0049] 6 is a top view of the manhole with the lid 12 removed. The plate member 101 of the communication device 100 of this embodiment is installed so as to rest on the upper surface of the side wall 11. In addition, dummy spacers 13 having a thickness similar to that of the plate member 101 may be provided in other areas of the side wall 11.

[0050] By providing the dummy spacers 13, the lid 12 and the sidewall 11 are no longer in direct contact with each other, and therefore the heat of the lid 12 is not transferred directly to the sidewall 11. As a result, a temperature difference between the lid 12 and the sidewall 11 can be ensured. Furthermore, by providing the dummy spacers 13, a space is created between the lid 12 and the sidewall 11, and more radio waves leak from this space. As a result, the quality of communication with an external base station device can be improved.

[0051] Second Embodiment In the first embodiment, the second junction point of the thermoelectric power generating unit 103 is connected to the side wall 11 , but in the present embodiment, a case where the second junction point is connected to a part other than the side wall 11 will be described.

[0052] For example, if the hole is composed of a sidewall 11 and a bottom, the second junction point may be connected to the bottom of the hole. Alternatively, if a liquid such as water is present in the hole, the second junction point may be connected to the liquid by being located on the liquid surface or in the liquid. Alternatively, the second junction point may be connected to a gas pipe, water pipe, or the like located in the hole. In these cases, as described in the first embodiment, a heat transfer member such as a heat pipe may be used to connect the thermoelectric power generation unit 103 and the second junction point. In this case, the heat pipe or the like also constitutes the thermoelectric power generation unit 103.

[0053] That is, by connecting the second joint point to a member or medium that is not continuous with the lid 12, the temperature difference between the lid 12 and the second joint point can be utilized.

[0054] (Summary) The features of the communication device and the power supply device in each embodiment of the present invention have been described above.

[0055] The terms used in each embodiment are merely examples and may be replaced with synonymous terms or terms having the same functions.

[0056] The terms first, second, through Nth (N is an integer) used in each embodiment and in the claims are used to distinguish between two or more configurations or methods of the same type, and do not limit the order or superiority or inferiority.

[0057] The location where the communication device and power supply device of this embodiment are used is not limited to a manhole, handhole, or street gutter, but may be any location where a temperature difference can be ensured.

Claims

1. A communication device provided in a space having a hole formed by a side wall (11) and / or a bottom and a lid (12) covering the hole, A lid contact member (101) that acquires heat from the lid; a heat transfer member (102) connected to the lid contact member for transferring heat of the lid; a thermoelectric generator (103) having a first junction connected to the thermal transfer member and a second junction connected to the side wall or the bottom; A communication unit (104) that performs communication using the electric power generated by the thermoelectric power generation unit; A communication device (100) having:

2. The lid contact member is sandwiched between the lid and an upper surface of the side wall when the communication device is installed in the space. The communication device according to claim 1.

3. The lid contact member elastically deforms so that the back surface of the lid is subjected to stress. The communication device according to claim 1.

4. The heat transfer member is a heat pipe. The communication device according to claim 1.

5. Further, the thermoelectric power generating unit has a secondary battery (105) for storing the electric power generated by the thermoelectric power generating unit, The communication unit performs communication using power supplied from the secondary battery. The communication device according to claim 1.

6. Further, it has a primary battery (106), the communication unit performs communication using power supplied from the primary battery when the power stored in the secondary battery is insufficient.

6. The communication device according to claim 5.

7. The communication unit transmits an output signal of a sensor that acquires environmental information. The communication device according to claim 1.

8. The thermoelectric power generation unit has a rectifier circuit for converting AC to DC. The communication device according to claim 1.

9. A power supply device provided in a space formed of a hole formed by a side wall (11) and / or a bottom and a lid (12) covering the hole, A lid contact member (101) that acquires heat from the lid; a heat transfer member (102) connected to the lid contact member for transferring heat of the lid; a thermoelectric generator (103) having a first junction connected to the thermal transfer member and a second junction connected to the side wall or the bottom; A power supply unit (150) having