Wiring device supplying direct current power

Abstract

To effectively suppress temperature rise in a wiring device.SOLUTION: A wiring device 2 is installed in an embedded hole formed in the construction surface. The wiring device 2 includes a power conversion component that converts alternating current power to direct current power, a terminal 21 that outputs direct current power, a housing 30 that accommodates the power conversion component and terminal 21, a first temperature detection element 22 that detects the temperature of a first portion within the housing 30 that is closer to the terminal 21, a second temperature detection element 23 that detects the temperature of a second portion within the housing 30 that is farther from the terminal 21 than the first portion, and a control unit 24. The control unit 24 controls the direct current power output from the terminal 21 on the basis of the temperatures detected by temperature detection elements 22, 23.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a wiring device that supplies DC power, and more particularly to a wiring device that supplies DC power and has a USB (Universal Serial Bus) terminal. [Background technology]

[0002] USB outlets have been widely used as wiring devices for supplying DC power to electronic devices such as smartphones, tablets, and laptops. Wiring devices such as USB outlets include a power conversion component that converts AC power to DC power, a terminal that outputs the DC power, and a housing that houses the power conversion component and terminal. Power conversion components generate heat during operation, but the impact of this heat generation has not traditionally been a major issue. However, in recent years, wiring devices have become increasingly powerful and compact, significantly increasing the heat density, defined as the power output per unit volume.

[0003] Patent Document 1 discloses a USB power supply device that aims to achieve a protection function against temperature rise with a small number of electronic components. The USB power supply device in Patent Document 1 is equipped with a power supply circuit that includes a photocoupler having a light-emitting circuit that emits light in an amount corresponding to the voltage at the terminals and a light-receiving circuit that receives the light emitted by the light-emitting circuit, a control circuit that controls the switching of a switching element in accordance with the amount of light received by the light-receiving circuit, and a temperature detection circuit that uses a thermistor to detect the temperature of at least one of the terminals and the semiconductor element and controls the light-emitting circuit in accordance with the detected temperature. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-118177 Summary of the Invention [Problem to be solved by the invention]

[0005] Although the USB power supply device of Patent Document 1 has a function for protecting against temperature rise, there is still room for improvement in terms of efficiently suppressing heat generation in the wiring device and improving safety while ensuring sufficient convenience for users. The object of the present disclosure is to effectively suppress temperature rise in the wiring device. [Means for solving the problem]

[0006] The wiring device for supplying DC power according to the present disclosure is a wiring device that is installed in a recessed hole formed in a building surface, and is characterized by comprising: a power conversion component that converts AC power into DC power; a terminal that outputs the DC power; a housing that accommodates the power conversion component and the terminal; a first temperature detection element that detects the temperature of a first portion within the housing that is closer to the terminal; a second temperature detection element that detects the temperature of a second portion within the housing that is farther from the terminal than the first portion; and a control unit that controls the DC power output from the terminal based on the temperatures detected by the first and second temperature detection elements. [Effects of the Invention]

[0007] The wiring fixture for supplying DC power according to the present disclosure can effectively suppress temperature rise in the fixture, and is suitable for, for example, fixtures with high heat density. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view of an outlet using a wiring fixture for supplying DC power according to an embodiment; [Figure 2] 1 is a perspective view of a wiring fixture according to an embodiment; [Figure 3] 1 is a perspective view of a wiring accessory according to an embodiment, showing a state in which a second member of a main body that constitutes a housing and a cover have been removed. [Figure 4] 1 is a side view of a wiring fixture according to an embodiment, showing a state in which a cover is removed; [Figure 5] 1 is a block diagram showing a configuration of a wiring fixture according to an embodiment; [Figure 6] 10 is a flowchart illustrating a control procedure of a wiring fixture according to an embodiment. [Figure 7] 10 is a flowchart showing a first example of output control. [Figure 8] 10A and 10B are diagrams illustrating an example of changes over time in (a) maximum output power and (b) temperatures T1 and T2 in the first output control example. [Figure 9] 10A and 10B are diagrams showing another example of changes over time in (a) maximum output power and (b) temperatures T1 and T2 in the first output control example. [Figure 10] 10A and 10B are diagrams showing another example of changes over time in (a) maximum output power and (b) temperatures T1 and T2 in the first output control example. [Figure 11] 10 is a flowchart showing a second example of output control. [Figure 12] 10A and 10B are diagrams illustrating an example of changes over time in (a) maximum output power and (b) temperatures T1 and T2 in the second output control example. [Figure 13] 10A and 10B are diagrams showing another example of the change over time in (a) the maximum output power and (b) the temperatures T1 and T2 in the second output control example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an example of an embodiment of a wiring device for supplying DC power according to the present disclosure will be described in detail with reference to the drawings. Note that the scope of the present disclosure includes configurations that selectively combine the components of the multiple embodiments and variations described below.

[0010] FIG. 1 is a diagram showing an outlet 1 using a wiring device 2 (hereinafter simply referred to as "wiring device 2") that supplies DC power, which is an example of an embodiment. As shown in FIG. 1, the outlet 1 is a wiring device that includes two wiring devices 2 and one power outlet device 3, and is installed on a wall 100, which is a construction surface of a building. A recessed hole is formed in the wall 100, and the wiring device 2 and the power outlet device 3 are inserted into the recessed hole. That is, the wiring device 2 is installed in the recessed hole formed in the wall 100.

[0011] The outlet 1 includes a frame-shaped decorative plate 4 with an opening 4a formed therein, through which the front surface 2a of the wiring fixture 2 and the front surface 3a of the power outlet device 3 are exposed. The decorative plate 4 is a rectangular frame-shaped plate when viewed from the front, and covers the recessed hole formed in the wall 100, the mounting frame installed around the recessed hole, and the like so that they are not visible. The outlet 1 includes, for example, a frame-shaped metal plate that is screwed to the mounting frame. The decorative plate 4 is fixed to the metal plate, for example, by hooking claws formed on its back surface into holes in the metal plate. The shape of the decorative plate when viewed from the front is not particularly limited, and may be, for example, circular.

[0012] The outlet 1 is installed with only the front faces 2a, 3a of the wiring device 2 and the power outlet device 3 exposed from the opening 4a in the decorative plate 4, and most of the wiring device 2 and the power outlet device 3 inserted into the recessed hole. As will be described in detail later, the wiring device 2 includes a power conversion component 11 (see FIG. 3 described later) that converts AC power supplied via the power line 31 into DC power output from the terminal 21, and is provided with a heat dissipation path for dissipating heat generated when the power conversion component 11 is operating to the outside of the device. However, because the front face 2a of the wiring device 2 is a part that the user may touch, the wiring device 2 is configured to suppress temperature rise in particular on the front face 2a.

[0013] In the example shown in FIG. 1 , the outlet 1 is installed on the wall 100 so that two wiring devices 2 are disposed adjacent to each other and the wiring devices 2 and the power outlet device 3 are aligned vertically. The connection ports 2b of the two wiring devices 2 and the connection port 3b of the power outlet device 3 are provided on the front of the outlet 1 so as to be aligned vertically. Although the two wiring devices 2 are disposed above the power outlet device 3, in an outlet equipped with the wiring devices 2, their arrangement is not particularly limited, and the number of wiring devices 2 is not particularly limited. Furthermore, the outlet equipped with the wiring devices 2 may include an optical outlet, a LAN outlet, a telephone line outlet, etc. instead of the power outlet device 3, or may include only the wiring device 2.

[0014] For ease of explanation, terms indicating front-to-rear, up-down, and left-to-right directions are used in this specification for the outlet 1, the wiring device 2, and each component of the wiring device 2. The front-to-rear direction refers to the direction in which a connector connected to the wiring device 2 is inserted and removed. The up-down direction is the direction along the vertical direction, and the left-to-right direction is the direction perpendicular to the up-down and front-to-rear directions. The left and right refer to the left and right when viewing the wiring device 2 from the front.

[0015] An example of the wiring fixture 2 is a USB outlet device. The USB outlet device is a device to which a USB connector 102 can be connected, includes a power conversion component that converts AC power into DC power, and supplies DC power to an electronic device 101 such as a smartphone, a tablet terminal, or a laptop computer. In FIG. 1 , the USB connector 102 of a cable 103 extending from the electronic device 101 is connected to the wiring fixture 2. The electronic device 101 is charged by DC power supplied from the wiring fixture 2 via the cable 103. In this embodiment, the wiring fixture 2 will be described as a USB outlet device. The power outlet device 3 is a general outlet device that outputs 100V or 200V AC power.

[0016] In this specification, the term "USB" includes various generations (transfer speed standards) of USB, such as USB 1.0, USB 1.1, USB 2.0, USB 3.0, USB 3.1, USB 3.2, and USB 4. The shape of the USB terminal is not particularly limited and may be any of A-terminal, B-terminal, C-terminal, mini USB, micro USB, etc. In the example shown in FIG. 1 , an outlet 1 including a wiring apparatus 2 is installed on a wall 100 of a building. However, the wiring apparatus 2 may also be installed on furniture such as a desk, shelf, countertop, or bed, or on vehicles such as automobiles, airplanes, and railroad cars. In other words, the surface on which the wiring apparatus 2 is installed is not limited to the surface of a building, but may also be the surface of furniture, vehicles, etc. Furthermore, the outlet 1 has a vertical mounting frame, and the wiring apparatus 2 and the power outlet device 3 are arranged vertically side by side, but the mounting frame of the outlet is not limited to the vertical type and may be, for example, horizontal.

[0017] 2 and 3 are perspective views of the wiring fixture 2. Fig. 4 is a side view of the wiring fixture 2. Fig. 3 shows a state in which the second member 42 and the cover 50 of the main body 40 that constitutes the housing 30 have been removed, and Fig. 4 shows a state in which the cover 50 has been removed. Note that in this embodiment, the first substrate 10, the second substrate 20, and the cover 50 are attached to the main body 40 as a single unit, but for ease of explanation, the figure shows a state in which only the cover 50 has been removed.

[0018] As shown in FIGS. 2 to 4, the wiring device 2 includes a first board 10 on which a power conversion component 11 that converts AC power into DC power is mounted, a second board 20 on which terminals 21 that output the DC power converted by the power conversion component 11 are mounted, and a housing 30 that houses the power conversion component 11 and the terminals 21. The housing 30 includes a main body 40 that is inserted into a recessed hole (inside the wall 100) formed in the wall 100, and a cover 50 that is attached to the main body 40 and exposed outside the recessed hole. The wiring device 2 has an overall external shape that is approximately rectangular, with the vertical length < the horizontal length < the front-to-rear length. The external shape of the wiring device is not particularly limited, and may be, for example, approximately cubic.

[0019] The wiring device 2 further includes a first temperature detection element 22 that detects the temperature of a first portion within the housing 30 that is closer to the terminal 21, a second temperature detection element 23 that detects the temperature of a second portion that is farther from the terminal 21 than the first portion, and a control unit 24. The control unit 24 is configured to control the DC power output from the terminal 21 based on the temperatures detected by the temperature detection elements 22 and 23. As will be described in detail later, when the temperatures detected by the temperature detection elements 22 and 23 increase, the control unit 24 gradually reduces the maximum output power in accordance with the temperature.

[0020] The wiring device 2 further includes a power line 31 connected to the first board 10. The power line 31 is fixed to the main body 40 of the housing 30 via a bush 32, and is connected to an electric wire (not shown) that is connected to a commercial AC power source outside the housing 30. In this case, there is no need to provide a terminal member such as a quick-connect terminal inside the housing 30, and the wiring device 2 can be made more compact. Furthermore, by using the bush 32, it is possible to prevent the power line 31 from becoming detached from the first board 10 during installation of the wiring device 2, etc.

[0021] A cover 50 constituting the housing 30 of the wiring device 2 is formed with a connection port 2b, which is an opening into which a USB connector 102 can be inserted, and the surface of the cover 50 forms the front surface 2a of the wiring device 2 in the outlet 1. That is, the wiring device 2 is fixed to the mounting frame of the outlet 1 so that the surface of the cover 50 on which the connection port 2b is formed is exposed through the opening 4a of the decorative plate 4. The main body 40 of the housing 30 is disposed inside the wall 100 and is not disposed in a location that is accessible by the user's hands under normal use conditions. Heat generated by the power conversion component 11 is dissipated to the outside of the device via the main body 40. Some of the heat may be transferred to the cover 50, causing the cover 50 to become hot.

[0022] The wiring device 2 further includes a heat dissipation member 33 interposed between the power conversion component 11 and the inner surface of the main body 40 of the housing 30. The heat dissipation member 33 is, for example, a sheet-like member that abuts the surface of the power conversion component 11 and the inner surface of the main body 40. In this case, a heat dissipation path is formed from the power conversion component 11, which is the heat source, to the main body 40 via the heat dissipation member 33. As the wiring device 2 becomes higher output and smaller, the heat density of the device increases significantly, but by providing the heat dissipation member 33, a heat dissipation structure with low contact thermal resistance and excellent heat dissipation properties can be formed.

[0023] First substrate 10 is an insulating substrate on which electronic components including power conversion components 11 are mounted. First substrate 10 is, for example, a printed wiring board including an AC / DC conversion circuit 12, a DC / DC converter 13, etc., which will be described later. First substrate 10 is mounted with power conversion components 11, such as AC / DC conversion circuit 12 and DC / DC converter 13, that convert AC power into DC power output from terminals 21. Power conversion components 11 generate heat during operation, with the semiconductor switching elements and transformer that constitute DC / DC converter 13 and the diode bridge that constitutes AC / DC conversion circuit 12 generating particularly large amounts of heat. Electronic components may be mounted on both sides of the insulating substrate of first substrate 10.

[0024] The second substrate 20 is a printed wiring board with terminals 21 mounted on an insulating substrate, and is electrically connected to the first substrate 10. The second substrate 20 includes, for example, an output circuit for outputting DC power converted by the power conversion component 11 of the first substrate 10 from the terminals 21. In this embodiment, the second substrate 20 is disposed perpendicular to the first substrate 10. The second substrate 20 has electronic components such as the terminals 21, a temperature detection element 22, a control unit 24, and an electrolytic capacitor mounted on a first surface of the insulating substrate facing in the opposite direction to the first substrate 10. Note that the second substrate 20 does not have electronic components that generate a large amount of heat, such as the power conversion component 11. In other words, the amount of heat generated during operation is greater for the first substrate 10 than for the second substrate 20.

[0025] The second substrate 20 is disposed within the housing 30 with the first surface of the insulating substrate parallel to the vertical and horizontal directions and facing forward of the second substrate 20. The terminal 21 is disposed, for example, in the center of the first surface of the insulating substrate. The terminal 21 is a USB terminal to which the USB connector 102 can be connected, and is formed into a flat, cylindrical shape overall. The terminal 21 is disposed in a state in which the USB connector 102 can be inserted and removed through a connection port 2b formed in the cover 50 of the housing 30. In the example shown in FIG. 3, there is one terminal 21, but the number of terminals 21 is not particularly limited and may be two or more.

[0026] The housing 30 has a main body 40 that houses the power conversion component 11 and a cover 50 attached to the main body 40. As described above, the cover 50 forms the front surface 2a of the wiring device 2 that the user may touch, while the main body 40 is disposed in a recessed hole formed in the wall 100. For this reason, switching elements, transformers, diode bridges, and the like that generate a large amount of heat are disposed inside the main body 40. The main body 40 is composed of a first member 41 formed in a tray shape and a second member 42 that is a lid that closes the opening of the first member 41. In this embodiment, the first board 10 and the second board 20 are housed in the first member 41.

[0027] The main body 40 may be made of resin, but is preferably made of metal. The main body 40 is preferably made of a metal material to efficiently dissipate heat transferred from the heat source to the outside of the appliance. The metal constituting the main body 40 is not particularly limited, but aluminum or an aluminum alloy is preferred from the viewpoints of thermal conductivity, lightness, processability, etc. The first member 41 of the main body 40 includes a rectangular main wall extending in the front-rear and left-right directions, and side walls formed perpendicular to the main wall along each side of the main wall. The second member 42 is a plate-like member that is rectangular in plan view, is arranged parallel to the main wall of the first member 41, and is fixed to the side walls of the first member 41. The structure of the housing 30 described here is an example.

[0028] The main body 40 has an opening 41a formed in a side wall (front wall) located on the front side of the wiring fixture 2. A holding portion 41b for holding the second board 20 and the cover 50 is formed near the opening 41a of the first member 41. The holding portion 41b is formed so that the second board 20 can be inserted therein and holds an end portion of the second board 20. The cover 50 is attached to the first member 41 by being inserted between the holding portion 41b and the front wall of the first member 41. The second board 20 is held by the holding portion 41b with the terminals 21 protruding forward from the opening 41a.

[0029] The cover 50 is a member having a connection port 2b, which is an opening into which the USB connector 102 can be inserted, and accommodates the terminals 21 protruding from the opening 41a of the main body 40 to close the opening 41a. The cover 50 may be made of metal, but is preferably made of a resin material that does not easily transfer heat from the power conversion component 11. The resin that makes up the cover 50 is not particularly limited, but examples include urea resin, melamine resin, and ABS resin. The cover 50 has a pair of protrusions 51 that protrude in the left and right directions. The cover 50 is attached to the main body 40 by inserting the protrusions 51 between the holding portion 41b and the front wall of the main body 40.

[0030] The heat dissipation member 33 is interposed between the power conversion components 11 (e.g., switching elements, transformers, diode bridges, etc.) and the inner surface of the main body 40, and forms a heat dissipation path for transmitting heat from the power conversion components 11 to the main body 40. The heat dissipation member 33 may be in contact with the insulating substrate that constitutes the first substrate 10. The heat dissipation member 33 is, for example, a compressible elastic body with high thermal conductivity. One example of a suitable heat dissipation member 33 is a sheet-like member made of flexible resin and thermally conductive filler dispersed in the resin. The thickness of the heat dissipation member 33 is, for example, 0.3 mm or more and 2.0 mm or less.

[0031] The resin constituting the heat dissipation member 33 may be any flexible material that is elastically deformable, examples of which include silicone resin, acrylic resin, urethane resin, and epoxy resin. The thermally conductive filler dispersed in the resin is preferably an insulating filler with high thermal conductivity, examples of which include aluminum oxide, aluminum nitride, and boron nitride. The heat dissipation member 33 may be adhesive and may be attached to the surface of the power conversion component 11, the inner surface of the housing 30, or the like. This makes it easier to position the heat dissipation member 33. Alternatively, the heat dissipation member 33 may be attached to the desired location using an adhesive, adhesive tape, or the like.

[0032] The heat dissipation member 33 is preferably disposed in a compressed state. In this case, the effect of reducing contact thermal resistance becomes more pronounced. The degree of compression (compression rate) of the heat dissipation member 33 is not particularly limited, but is preferably 10% or more, more preferably 20% or more, and particularly preferably 30% or more. The compression rate is calculated using the formula [(thickness in uncompressed state - thickness in compressed state) x 100 / thickness in uncompressed state]. The heat dissipation member 33 is in a compressed state, for example, when the second member 42 constituting the main body 40 is assembled to the first member 41.

[0033] The heat dissipation member 33 may be a graphene sheet or a metal heat dissipation plate. In particular, when the main body 40 is made of a resin material, it is preferable to use a graphene sheet or a metal heat dissipation plate as the heat dissipation member 33. When the main body 40 is made of resin, the heat dissipation performance is likely to be lower than when it is made of metal, but using a graphene sheet or a metal heat dissipation plate can form an excellent heat dissipation path. It is preferable that the graphene sheet and the metal heat dissipation plate are arranged in contact with and pressed against the surface of the power conversion component 11 and the inner surface of the main body 40.

[0034] As described above, the wiring apparatus 2 includes the first temperature detection element 22, the second temperature detection element 23, and the control unit 24 that controls the DC power output from the terminal 21 based on the temperatures detected by the temperature detection elements 22 and 23. The temperature detection element 22 detects the temperature of a first portion close to the terminal 21, and the temperature detection element 23 detects the temperature of a second portion that is farther from the terminal 21 than the first portion. The wiring apparatus 2 may also include a third temperature detection element. The control unit 24 effectively suppresses temperature rise in the apparatus by controlling the maximum output power based on the temperatures of two or more different portions.

[0035] The temperature of the first portion, which is close to the terminal 21, must be maintained at a temperature that is safe for the user to touch, for example. On the other hand, the second portion, which is farther from the terminal 21, is inserted into the embedding hole (the internal space of the construction material), so its temperature may be higher than that of the first portion. However, it is undesirable for the temperature to become too high from the standpoint of thermal impact on the surrounding area and protection of the electronic components that make up the device. In particular, if there are components in the internal space of the construction material that are susceptible to thermal degradation, or if there are adjacent wiring devices, it is necessary to suppress the thermal impact on these components. Furthermore, if the temperature of the second portion rises, the heat is transferred to the first portion, causing the temperature of the first portion to also rise. Because the degree of temperature rise in the first and second portions varies depending on the usage state of the wiring device 2, the surrounding environment, etc., simply considering the temperature of one portion makes it difficult to appropriately suppress the temperature rise in each portion, which may result in excessive output suppression and impair user convenience.

[0036] The wiring device 2 addresses the above-mentioned problem by controlling the maximum output power based on the temperatures of a first portion close to the terminal 21 and a second portion inserted into the mounting hole away from the terminal 21. Specifically, the first portion is the portion located in the range from the second board 20 to the front surface 2a of the wiring device 2, the temperature of which is detected by the temperature detection element 22, and the second portion is the portion located behind the second board 20 on the wiring device 2, the temperature of which is detected by the temperature detection element 23. The wiring device 2 can control the maximum output power so as to avoid excessive output suppression while ensuring sufficient safety for end users during use, without causing discomfort. Furthermore, because the temperature of the second portion located in the interior space of a building material is also appropriately suppressed, builders (including manufacturers of fixtures, etc.) who install the wiring device 2 in building materials can safely design buildings, fixtures, etc., while minimizing increases in cost and size.

[0037] Although it is possible to measure the surface temperature of the cover 50 using the temperature detection element 22, it is not easy to accurately measure the surface temperature of the cover 50, especially when the cover 50 is made of resin. Therefore, in this embodiment, the temperature of the terminal 21 is measured using the temperature detection element 22.

[0038] The temperature detection element 22 is preferably mounted on the first surface of the second substrate 20 facing the front of the wiring fixture 2. The terminal 21 is mounted in the center of the first surface of the second substrate 20, standing perpendicular to the first surface. The temperature detection element 22 is disposed near the terminal 21 on the first surface of the second substrate 20 and detects the temperature of the terminal 21. Since the temperature of the first surface of the second substrate 20 near the terminal 21 is substantially equal to the temperature of the terminal 21, the temperature of the terminal 21 can be detected by disposing the temperature detection element 22 near the terminal 21. Note that although the temperature detection element 22 can also be disposed on the outer peripheral surface of the terminal 21, it is preferable to dispose it on the first surface of the second substrate 20 from the viewpoint of productivity, etc.

[0039] A thermistor (substrate thermistor) is used for the temperature detection element 22. The temperature detection element 22 detects the temperature of the terminals 21 by detecting the temperature of the first surface of the second substrate 20. For this reason, the temperature detection element 22 is disposed in an area on the first surface of the second substrate 20 where the temperature is substantially equal to the temperature of the terminals 21. Since the temperature of the terminals 21 is similar to the temperature of the front surface 2a of the cover 50 that the user can touch, and the temperature of the cover 50 is generally highest near the terminals 21, detecting the temperature of the terminals 21 can effectively suppress a temperature rise in the cover 50. Note that the control unit 24 may estimate the temperature of the front surface 2a of the cover 50 from the temperature detected by the temperature detection element 22 and control the maximum output power based on the estimated value.

[0040] The temperature detection element 23 may be a substrate thermistor like the temperature detection element 22, but is preferably attached to the housing 30 and detects the temperature of the housing 30. A lead-type thermistor including an element body 23a and lead wires 23b extending from the element body 23a is used for the temperature detection element 23. In this embodiment, the element body 23a of the temperature detection element 23 is attached to the inner surface of the main body 40 of the housing 30 and detects the temperature of the main body 40. The lead wires 23b extending from the element body 23a may be connected to the first substrate 10, but are preferably connected to the second substrate 20 on which the control unit 24 is mounted. The temperature of the main body 40 detected by the element body 23a is transmitted to the control unit 24 of the second substrate 20 via the lead wires 23b.

[0041] The element body 23a of the temperature detection element 23 may be fixed to the inner surface of the main body 40 using screws, or using adhesive or adhesive tape. When the main body 40 is made of metal, heat transferred to the main body 40 is likely to diffuse throughout the main body 40. For this reason, the element body 23a may be fixed to any position on the main body 40, but is preferably fixed near the second substrate 20, for example, because the lead wires 23b need to be connected to the second substrate 20. The element body 23a is fixed to the side wall of the main body 40, for example, closer to the opening 41a than the center of the main body 40 in the front-to-rear direction.

[0042] Control unit 24 is a microcomputer that controls the DC power output from terminal 21 based on the temperatures detected by temperature detection elements 22 and 23, and is mounted on second board 20. As described above, control unit 24 is disposed on the first surface of second board 20 facing the front of wiring fixture 2. Control unit 24 can also be disposed on the second surface of second board 20 facing the rear of wiring fixture 2, or on first board 10. However, disposing control unit 24 on the first surface of second board 20 has the advantage of making it easier to ensure insulation and reducing the influence of heat from power conversion component 11. Control unit 24 is composed of, for example, a memory that stores programs, a processor that executes programs, a timer, an A / D converter, a D / A converter, an input / output circuit, etc.

[0043] 5 is a block diagram showing the configuration of the wiring device 2, illustrating a state in which the electronic device 101 is connected to the terminal 21. As described above, the electronic device 101 is connected to the terminal 21 by inserting the USB connector 102 of the cable 103 into the connection port 2b.

[0044] 5 , the wiring device 2 includes an AC / DC conversion circuit 12, a DC / DC converter 13, a detection circuit 14, a breaker 15, a communication unit 16, and a memory unit 17. In the present embodiment, the AC / DC conversion circuit 12 and the DC / DC converter 13 are provided on a first substrate 10, and the detection circuit 14, the breaker 15, the communication unit 16, and the memory unit 17 are provided on a second substrate 20. The control unit 24 controls the operation of the DC / DC converter 13 to control the DC power output from the terminal 21, for example, based on the temperature of the terminal 21 detected by the temperature detection element 22 and the temperature of the main body 40 detected by the temperature detection element 23.

[0045] AC / DC conversion circuit 12 is a circuit that converts AC power supplied from an AC power source via power line 31 into DC power, and includes, for example, a diode bridge and a smoothing capacitor. DC / DC converter 13 further converts the DC power supplied from AC / DC conversion circuit 12 and outputs the converted power to terminal 21. DC / DC converter 13 includes, for example, a switching element, a control circuit that controls the switching element, a transformer, an inductor, a diode, etc. DC / DC converter 13 outputs a predetermined DC voltage under the control of control unit 24.

[0046] Detection circuit 14 is a circuit that detects at least one of DC power and DC current, and includes, for example, a shunt resistor that detects DC current. Control of the output voltage is achieved by performing constant voltage control so that DC / DC converter 13 outputs a DC voltage instructed by control unit 24. Control of the maximum output power is achieved by having control unit 24 monitor the current detected by detection circuit 14 and feedback control DC / DC converter 13 so that the current does not exceed a current corresponding to the maximum output power (maximum output current).

[0047] The interrupter 15 is configured, for example, by a circuit that interrupts the output of the DC / DC converter 13, and includes a MOS transistor or the like. The control unit 24 controls the interrupter 15 to stop the output from the DC / DC converter 13 when the DC current detected by the detection circuit 14 exceeds a predetermined value. The communication unit 16 is configured, for example, by a communication interface circuit for communicating with the electronic device 101 connected to the terminal 21. The storage unit 17 is configured, for example, by a nonvolatile semiconductor memory, and stores an output control table that defines the relationship between the output voltage and the maximum output current of the DC / DC converter 13.

[0048] Tables 1 to 3 show examples of output control tables. As shown in Tables 1 to 3, the output control tables specify the maximum output current corresponding to each of four output voltages (5V, 9V, 15V, and 20V). Tables 1 to 3 are output control tables when the maximum output power is a first maximum output power, a second maximum output power, and a third maximum output power, respectively. The relationship between the maximum output powers is first maximum output power > second maximum output power > third maximum output power. For example, the first maximum output power is set to 60 W, the second maximum output power is set to 45 W, and the third maximum output power is set to 30 W.

[0049] [Table 1]

[0050] [Table 2]

[0051] [Table 3]

[0052] Table A in Table 1 is applied when the temperature detected by the temperature detection elements 22 and 23 is low and output control to suppress a temperature rise is not executed. As will be described in detail later, when the temperature detected by the temperature detection element 22 is equal to or lower than the first suppression temperature and the temperature detected by the temperature detection element 23 is equal to or lower than the second suppression temperature, the control unit 24 executes control using Table A. Table B in Table 2 is applied when the temperature detected by the temperature detection elements 22 and 23 exceeds the first or second suppression temperature. Table C in Table 3 is applied when the temperature of the wiring device 2 becomes even higher. In other words, Tables A to C are output control tables in which maximum output power is determined corresponding to a plurality of temperature setting values.

[0053] The control unit 24 acquires the temperatures detected by the temperature detection elements 22 and 23, and controls the DC / DC converter 13 based on an output control table corresponding to the temperature. Furthermore, before supplying DC power to the electronic device 101 connected to the terminal 21, the control unit 24 negotiates the output voltage via the communication unit 16 and the communication terminal of the electronic device 101. The control unit 24 transmits, for example, table A stored in the storage unit 17 to the electronic device 101, and receives information on the requested voltage (the voltage to be supplied from the wiring fixture 2) from the electronic device 101. The control unit 24 transmits a control signal to the DC / DC converter 13 to cause it to output the requested voltage of the electronic device 101. As a result, the requested voltage of the electronic device 101 is output from the terminal 21.

[0054] The negotiation may be performed each time the table used for output control is switched due to a change in the temperature detected by the temperature detection elements 22 and 23. The items to be negotiated may include not only the output voltage but also the maximum output current and the maximum output power.

[0055] When the temperature detected by the temperature detection element 22 exceeds the first suppression temperature, or when the temperature detected by the temperature detection element 23 exceeds the second suppression temperature, the control unit 24 suppresses the maximum output power output from the terminal 21 to a second maximum output power (45 W) that is lower than the first maximum output power (60 W). By suppressing the maximum output power, it is possible to suppress a temperature rise in the wiring apparatus 2 while continuing to supply power to the electronic device 101. Hereinafter, the temperature detected by the temperature detection element 22 will be referred to as a "first temperature T1" or simply as temperature T1, and the temperature detected by the temperature detection element 23 will be referred to as a "second temperature T2" ​​or simply as temperature T2.

[0056] The suppression temperature is a threshold value used to determine whether or not to suppress the maximum output power (suppression determination), and the second suppression temperature is set to a temperature higher than the first suppression temperature. For example, the first suppression temperature is set to 50°C or higher and 65°C or lower, and the second suppression temperature is set to 70°C or higher and 85°C or lower. A plurality of first and second suppression temperatures may be set.

[0057] The control unit 24 may further stop the output of DC power when the first temperature T1 exceeds a third suppression temperature higher than the first suppression temperature, or when the second temperature T2 exceeds a fourth suppression temperature higher than the third suppression temperature. The control unit 24 can stop the output of DC power to the electronic device 101, for example, by controlling the DC / DC converter 13 or the circuit breaker 15. If the temperature rise of the wiring device 2 does not subside even after suppressing the maximum output power, the control unit 24 stops the output of DC power, i.e., sets the maximum output power to 0 W, thereby suppressing the temperature rise. For example, the third suppression temperature is set to a temperature higher than 65°C and equal to or lower than 80°C, and the fourth suppression temperature is set to a temperature higher than 80°C and equal to or lower than 95°C.

[0058] For example, after the first temperature T1 exceeds the first suppression temperature or after the second temperature T2 exceeds the second suppression temperature, if the first temperature T1 falls below the first return temperature and the second temperature T2 falls below the second return temperature, the control unit 24 returns the maximum output power to the first maximum output power. That is, if the temperature of the wiring device 2 drops as a result of suppressing the maximum output power to the second maximum output power, the control unit 24 increases the maximum output power to enable the output of the voltage required by the electronic device 101, thereby improving user convenience. By suppressing the maximum output power based on one of the temperatures T1 and T2 and releasing the suppression of the maximum output power based on both the temperatures T1 and T2, safety can be sufficiently ensured.

[0059] The return temperature is a threshold value used to determine whether or not to release the suppression of maximum output power (return determination), and the second return temperature is set to a temperature higher than the first return temperature. For example, the first return temperature is set to 40°C or higher and 65°C or lower, and the second return temperature is set to 60°C or higher and 85°C or lower. A plurality of first and second return temperatures may be set.

[0060] As will be described in detail later, when the first temperature T1 or the second temperature T2 increases, the control unit 24 gradually reduces the maximum output power in accordance with the temperature. Then, when the first temperature T1 or the second temperature T2 decreases, the control unit 24 gradually increases the reduced maximum output power or returns it to the initial maximum output power before reduction in accordance with the temperature. Furthermore, it is preferable that the control unit 24 acquires the first temperature T1 every first period and uses it for controlling the output of DC power, and calculates the average or median value of the second temperature T2 during the second period and uses it for controlling the output of DC power. Here, the second period is set to be longer than the first period.

[0061] A first example of output control in the wiring apparatus 2 will be described below with reference to Figures 6 to 10. The control procedure shown in Figure 6 is also the same for a second example of control, which will be described later.

[0062] 6, when the wiring apparatus 2 detects that the electronic device 101 is connected to the terminal 21 (Yes in step S1), it negotiates to acquire information about the required voltage from the electronic device 101 (step S2). For example, if the temperatures T1 and T2 at the time when the connection of the electronic device 101 is detected are equal to or lower than the suppression temperatures, the control unit 24 transmits Table A of Table 1 to the electronic device 101 and receives the information about the required voltage from the electronic device 101. The connection of the electronic device 101 in step S1 is detected by receiving a signal from the communication terminal of the USB connector 102.

[0063] When control unit 24 acquires the information on the required voltage from electronic device 101, it sends a control signal to DC / DC converter 13 to output the required voltage, and controls the DC power (DC voltage) output from terminal 21 (step S3). Control unit 24 also monitors the current detected by detection circuit 14, and performs feedback control on DC / DC converter 13 based on table A so that the current does not exceed the maximum output current. As will be described in detail later, in step S3, the maximum output power is controlled based on temperatures T1 and T2 detected by temperature detection elements 22 and 23.

[0064] When the control unit 24 detects that the electronic device 101 has been disconnected (Yes in step S4), the series of steps S3 and S4 ends. That is, regardless of which of steps S31 to S44 described below is in progress, when the USB connector 102 is removed from the terminal 21, the control procedure shown in FIG. 6 ends.

[0065] Fig. 7 is a flowchart showing the details of step S3. The following describes an example in which the temperature of the wiring apparatus 2 when the electronic device 101 is connected to the terminal 21 is room temperature (the same applies to Fig. 11 described later). As shown in Fig. 7, when the temperature of the wiring apparatus 2 is room temperature, the control unit 24 controls the DC power output from the terminal 21 based on the voltage required by the electronic device 101 so that the DC power does not exceed a first maximum output power (step S31). The first maximum output power is, for example, 60 W. The control unit 24 uses Table A to feedback-control the DC / DC converter 13 so that the current detected by the detection circuit 14 does not exceed a current corresponding to the first maximum output power (maximum output current).

[0066] The control unit 24 acquires the temperature T1 detected by the temperature detection element 22 and the temperature T2 detected by the temperature detection element 23 (step S32), and determines whether the temperature T1 exceeds 50°C and whether the temperature T2 exceeds 70°C (step S33). If the control unit 24 determines that the temperature T1 exceeds 50°C or that the temperature T2 exceeds 70°C (Yes in step S33), it suppresses the maximum output power to a second maximum output power that is lower than the first maximum output power (60 W) (step S34). The second maximum output power is, for example, 45 W. This suppresses a temperature rise in the wiring apparatus 2.

[0067] Step S33 and steps S37 and S41 described below are steps for making a suppression determination as to whether or not to suppress the maximum output power. If the control unit 24 determines that the temperature T1 does not exceed 50°C and the temperature T2 does not exceed 70°C (No in step S33), it continues steps S31 to S33. 50°C corresponds to the first suppression temperature, and 70°C corresponds to the second suppression temperature.

[0068] If control unit 24 determines in step S33 that temperature T1 exceeds 50°C or that temperature T2 exceeds 70°C (Yes in step S33), it switches the output control table to Table B of Table 2. Then, using Table B, it performs feedback control on DC / DC converter 13 so that the current detected by detection circuit 14 does not exceed the current corresponding to the second maximum output power (step S34). At this time, the negotiation in step S2 of FIG. 6 may be performed again.

[0069] Here, the acquisition of temperatures T1 and T2 in step S32 will be described. The control unit 24 acquires the first temperature T1 for each first period and calculates the average or median value of the second temperature T2 for the second period. The first period is set to be shorter than the second period. That is, the first temperature T1 is used for output control at shorter intervals than the second temperature T2. Because the first temperature T1 is close to the temperature of the front surface 2a of the cover 50 that the user can touch, it is preferable to perform output control to suppress temperature increases while also taking into account instantaneous temperature increases. For the second temperature T2, it is preferable to acquire more reliable temperature information and use it for output control from the perspective of preventing excessive output suppression and improving user convenience.

[0070] The control unit 24 may use the temperature information acquired from the temperature detection element 22 directly for output control, but preferably calculates the average or median value for the first period, as with the second temperature T2. It is particularly preferable to calculate a moving average value for the first temperature T1 for the first period and use it for output control. Similarly, it is preferable to calculate a moving average value for the second temperature T2 for the second period and use it for output control. The first period is, for example, from 0.1 to 5 seconds, or from 0.5 to 3 seconds. The second period is preferably from 10 to 50 times the first period, and more preferably from 20 to 40 times the first period. The second period is, for example, from 10 to 50 seconds, or from 20 to 40 seconds.

[0071] Control unit 24 acquires temperatures T1 and T2 (step S35) while controlling DC / DC converter 13 so that the maximum output power output from terminal 21 does not exceed the second maximum output power (45 W) (step S34). Then, it is determined whether temperature T1 has become 40°C or less and temperature T2 has become 60°C or less (step S36). Note that in temperature acquisition step S35, it is preferable to calculate moving average values ​​of temperatures T1 and T2, as in step S32. Unless otherwise specified, moving average values ​​of temperatures T1 and T2 are also calculated in other temperature acquisition steps described below.

[0072] When the control unit 24 determines that the temperature T1 is 40°C or less and the temperature T2 is 60°C or less (Yes in step S36), the control unit 24 returns the maximum output power to the first maximum output power (60 W) (step S31). That is, when the maximum output power is restricted to the second maximum output power (45 W) and the temperature of the wiring apparatus 2 drops, the restriction on the maximum output power is released.

[0073] Step S36 and steps S40 and S44 described below are steps for determining whether or not to release the suppression of the maximum output power. The temperature of 40°C in step S36 corresponds to the first return temperature, and 60°C corresponds to the second return temperature.

[0074] If the control unit 24 determines in step S36 that the temperature T1 exceeds 40°C or that the temperature T2 exceeds 60°C (No in step S36), the control unit 24 further determines whether the temperature T1 exceeds 60°C and whether the temperature T2 exceeds 80°C (step S37). If the control unit 24 determines that the temperature T1 exceeds 60°C or that the temperature T2 exceeds 80°C (Yes in step S37), the control unit 24 suppresses the maximum output power to a third maximum output power that is lower than the second maximum output power (45 W) (step S38). The third maximum output power is, for example, 30 W. This suppresses a temperature rise in the wiring apparatus 2.

[0075] If control unit 24 determines in step S37 that temperature T1 exceeds 60°C or that temperature T2 exceeds 80°C (Yes in step S37), it switches the output control table to Table C of Table 3. Then, using Table C, it performs feedback control on DC / DC converter 13 so that the current detected by detection circuit 14 does not exceed the current corresponding to the third maximum output power (step S38). At this time, the negotiation in step S2 of FIG. 6 may be performed again. On the other hand, if control unit 24 determines that temperature T1 does not exceed 60°C and that temperature T2 does not exceed 80°C (No in step S37), it continues steps S34 to S37.

[0076] The control unit 24 acquires temperatures T1 and T2 (step S39) while controlling the DC / DC converter 13 so that the maximum output power output from the terminal 21 does not exceed the third maximum output power (30 W) (step S38). Then, the control unit 24 determines whether the temperature T1 is equal to or lower than 40°C and the temperature T2 is equal to or lower than 60°C (step S40). If the control unit 24 determines that the temperature T1 is equal to or lower than 40°C and the temperature T2 is equal to or lower than 60°C (Yes in step S40), the control unit 24 returns the maximum output power to the first maximum output power (60 W) (step S31). That is, if the temperature of the wiring apparatus 2 drops after the maximum output power is restricted to the third maximum output power (30 W), the restriction on the maximum output power is lifted.

[0077] If the control unit 24 determines in step S40 that the temperature T1 exceeds 40°C or that the temperature T2 exceeds 60°C (No in step S40), it further determines whether the temperature T1 exceeds 70°C and whether the temperature T2 exceeds 90°C (step S41). If the control unit 24 determines that the temperature T1 exceeds 70°C or that the temperature T2 exceeds 90°C (Yes in step S41), it stops the output of DC power from the terminal 21 (step S42). That is, the maximum output power is set to 0 W.

[0078] If the temperature of the wiring apparatus 2 continues to rise even after the maximum output power is reduced to the third maximum output power, the control unit 24 stops the output of DC power to suppress further temperature rise (step S42). On the other hand, if the control unit 24 determines in step S41 that the temperature T1 does not exceed 70°C and the temperature T2 does not exceed 90°C (No in step S41), it continues steps S38 to S41.

[0079] While the output of DC power is stopped in step S42, the control unit 24 acquires temperatures T1 and T2 (step S43) and determines whether temperature T1 has become 40°C or less and temperature T2 has become 60°C or less (step S44). If the control unit 24 determines that temperature T1 has become 40°C or less and temperature T2 has become 60°C or less (Yes in step S44), it returns the maximum output power to the first maximum output power (60 W) (step S31) and cancels the suppression of the maximum output power.

[0080] Figures 8 to 10 are diagrams showing an example of changes over time in (a) maximum output power and (b) temperatures T1 and T2 in the first output control example shown in Figure 7. In the examples shown in Figures 8 to 10, it is assumed that electronic device 101 is charged at the maximum output power in each period.

[0081] 8 to 10 correspond to the first suppression temperature, and suppression temperatures T2[A] and T2[B] correspond to the second suppression temperature. Suppression temperature T1[C] corresponds to the third suppression temperature, and suppression temperature T2[C] corresponds to the fourth suppression temperature. Furthermore, return temperature T1[X] corresponds to the first return temperature, and suppression temperature T2[X] corresponds to the second return temperature.

[0082] In the example shown in FIG. 8, when charging of electronic device 101 begins with 60 W of power, temperatures T1 and T2, which were 30° C. at the start of charging, both rise, and temperature T2 exceeds suppression temperature T2[A] of 70° C. at time t1, causing the maximum output power to be suppressed to 45 W. At this time, temperature T1 has not yet reached suppression temperature T1[A], but the maximum output power is suppressed to 45 W. Although the maximum output power is suppressed to 45 W, charging of electronic device 101 can continue. As a result of suppressing the maximum output power to 45 W, temperature T2 falls below recovery temperature T2[X] of 60° C. at time t2, and temperature T1 falls below recovery temperature T1[X] of 40° C. In this case, control unit 24 returns the maximum output power to 60 W at time t2 and cancels the suppression of the maximum output power.

[0083] In the example shown in Fig. 8, temperature T2 exceeds 70°C again at time t3, the maximum output power is restricted to 45 W, and at time t4, temperature T2 falls to 60°C or less and temperature T1 falls to 40°C or less, and the restriction on the maximum output power is released. In the example shown in Fig. 8, steps S31 to S37 of the control procedure shown in Fig. 7 are repeated.

[0084] The example shown in FIG. 9 is similar to the example shown in FIG. 8 in that the temperature T2 exceeds the suppression temperature T2[A] of 70°C at time t1, and the maximum output power is suppressed to 45 W. Meanwhile, in the example shown in FIG. 9, as a result of suppressing the maximum output power to 45 W, the temperature rise slows down but continues, and the temperature T2 exceeds the suppression temperature T2[B] of 80°C at time t2, and the maximum output power is suppressed to 30 W. As a result of suppressing the maximum output power to 30 W, the temperature T2 falls below the return temperature T2[X] of 60°C at time t4, and the temperature T1 falls below the return temperature T1[X] of 40°C. In this case, the control unit 24 returns the maximum output power to 60 W at time t4 and cancels the suppression of the maximum output power. In the example shown in FIG. 9, steps S31 to S41 of the control procedure shown in FIG. 7 are executed.

[0085] The example shown in FIG. 10 is similar to the example shown in FIG. 9 in that temperature T2 exceeds suppression temperature T2[B] of 80°C at time t2, and the maximum output power is suppressed to 30 W. On the other hand, in the example shown in FIG. 10, as a result of suppressing the maximum output power to 30 W, the temperature rise slows down but continues, and temperature T2 exceeds suppression temperature T2[C] of 90°C at time t3, and the output of DC power is stopped (maximum output power 0 W). As a result of stopping the output of DC power, temperature T2 falls below return temperature T2[X] of 60°C at time t4, and temperature T1 falls below return temperature T1[X] of 40°C. In this case, control unit 24 returns the maximum output power to 60 W at time t4 and cancels the suppression of the maximum output power. In the example shown in FIG. 8, steps S31 to S44 of the control procedure shown in FIG. 7 are executed.

[0086] Fig. 11 is a flowchart showing a second example of step S3 in Fig. 6. As shown in Fig. 11, control unit 24 controls DC power output from terminal 21 based on the required voltage of electronic device 101 so as not to exceed the first maximum output power (60 W) (step S301). Note that steps S301 to S309 are similar to steps S31 to S39 in Fig. 7, and therefore redundant explanations will be omitted. However, step S306 in Fig. 11 differs from step S36 in Fig. 7 in that the return temperature corresponding to first temperature T1 is set to 45°C and the return temperature corresponding to second temperature T2 is set to 65°C.

[0087] In step S308, control unit 24 acquires temperatures T1 and T2 while controlling DC / DC converter 13 so that the maximum output power does not exceed the third maximum output power (30 W) (step S309), and determines whether temperature T1 has become 55°C or less and temperature T2 has become 75°C or less (step S310). If control unit 24 determines that temperature T1 has become 55°C or less and temperature T2 has become 75°C or less (Yes in step S310), it returns the maximum output power to the second maximum output power (45 W) (step S304).

[0088] 11 differs from the example shown in FIG. 7 in that in step S310, the maximum output power is returned to the second maximum output power (45 W), which is one step higher, rather than to the first maximum output power (60 W). That is, when temperature T1 or temperature T2 increases, control unit 24 reduces the maximum output power in stages in accordance with the temperature, and when temperature T1 or temperature T2 decreases, control unit 24 increases the reduced maximum output power in stages in accordance with the temperature. The example shown in FIG. 11 differs from the example shown in FIG. 7, in which the recovery temperature is constant in each recovery determination step, in that the recovery temperature used for recovery determination is different and set higher in stages.

[0089] If the control unit 24 determines in step S310 that the temperature T1 exceeds 55°C or that the temperature T2 exceeds 75°C (No in step S310), it further determines whether the temperature T1 exceeds 70°C and whether the temperature T2 exceeds 90°C (step S311). If the control unit 24 determines that the temperature T1 exceeds 70°C or that the temperature T2 exceeds 90°C (Yes in step S311), it stops the output of DC power from the terminal 21 (step S312). Steps S311 and S312 are the same as steps S41 and S42 in FIG. 7.

[0090] While the output of DC power is stopped in step S312, the control unit 24 acquires temperatures T1 and T2 (step S313) and determines whether temperature T1 has become 65°C or less and temperature T2 has become 85°C or less (step S314). If the control unit 24 determines that temperature T1 has become 65°C or less and temperature T2 has become 85°C or less (Yes in step S314), it cancels the output stop and returns the maximum output power (0 W) to the third maximum output power (30 W), which is one level higher (step S308).

[0091] Figures 12 and 13 are diagrams showing an example of (a) maximum output power and (b) temperature T1, T2 changes over time in the second output control example shown in Figure 11. In the examples shown in Figures 12 and 13, it is assumed that electronic device 101 is charged at the maximum output power in each period.

[0092] Note that the suppression temperatures T1[A] to T1[C], T2[A] to T2[C], and the return temperatures T1[X], T2[X] shown in FIGS. 12 and 13 are the same as those in FIGS. 8 to 10. The return temperatures T1[Y], T1[Z] correspond to the first temperature T1 and are used for the second-stage and third-stage return determinations, and are set such that T1[X] < T1[Y] < T1[Z]. The return temperatures T2[Y], T2[Z] correspond to the second temperature T2 and are used for the second-stage and third-stage return determinations, and are set such that T2[X] < T2[Y] < T2[Z].

[0093] In the example shown in FIG. 12, the temperatures T1 and T2, which were 30°C at the start of charging, continued to rise even when the maximum output power was suppressed to 45W at time t1, and at time t2, the maximum output power was suppressed to 30W when the temperature T2 exceeded the suppression temperature T2[B] of 80°C. As a result of suppressing the maximum output power to 30W, the temperature T2 became 75°C or less, which is the return temperature T2[Y], at time t3, and the temperature T1 became 55°C or less, which is the return temperature T1[Y]. In this case, the control unit 24 returns the maximum output power (30W) to the next higher level of 45W at time t3. In the example shown in FIG. 12, the temperature T2 exceeded 80°C again at time t4 and the maximum output power was suppressed to 30W, and steps S301 to S311 of the control procedure shown in FIG. 11 were executed.

[0094] In the example shown in FIG. 13, when the temperature T2 exceeded the suppression temperature T2[C] of 90°C at time t3, the maximum output power was set to 0W and the output of DC power from terminal 21 was stopped. As a result of stopping the output, the temperatures T1 and T2 rapidly decreased, and at time t4, the temperature T2 became 85°C or less, which is the return temperature T2[Z], and the temperature T1 became 65°C or less, which is the return temperature T1[Z]. In this case, the control unit 24 returns the maximum output power (0W) to the next higher level of 30W at time t4. In the example shown in FIG. 13, steps S301 to S314 of the control procedure shown in FIG. 11 were executed.

[0095] As described above, the wiring device 2 having the above configuration suppresses the maximum output power output from the terminal 21 based on the temperature of the terminal 21 detected by the first temperature detection element 22 and the temperature of the main body 40 detected by the second temperature detection element 23. This makes it possible to efficiently and appropriately suppress temperature increases in the cover 50, which the user may touch, and the main body 40, which is inserted into the mounting hole. Furthermore, the wiring device 2 is configured to quickly restore the maximum output power if the temperature drops due to the suppression of the maximum output power. This makes it possible to prevent excessive output suppression while more reliably ensuring safety and improving user convenience.

[0096] The present disclosure is further illustrated by the following embodiments. Configuration 1: A wiring device that is installed in a recessed hole formed in a building surface, the wiring device supplying DC power, comprising: a power conversion component that converts AC power into DC power; a terminal that outputs the DC power; a housing that accommodates the power conversion component and the terminal; a first temperature detection element that detects the temperature of a first portion within the housing that is closer to the terminal; a second temperature detection element that detects the temperature of a second portion within the housing that is farther from the terminal than the first portion; and a control unit that controls the DC power output from the terminal based on the temperatures detected by the first and second temperature detection elements. Configuration 2: The wiring device for supplying DC power described in Configuration 1, wherein the housing has a main body that is inserted into the embedding hole and a cover that is attached to the main body and exposed outside the embedding hole, and the second temperature detection element detects the temperature of the main body. Configuration 3: The wiring device for supplying DC power according to configuration 1 or 2, wherein the first temperature detection element detects the temperature of the terminal. Configuration 4: The wiring device for supplying DC power according to any one of configurations 1 to 3, wherein the control unit acquires a first temperature detected by the first temperature detection element for each first period and uses the first temperature for controlling the output of the DC power, calculates an average or median value of a second temperature detected by the second temperature detection element for each second period and uses the average or median value for controlling the output of the DC power, and the first period is shorter than the second period. Configuration 5: The wiring device for supplying DC power described in any one of configurations 1 to 3, wherein the control unit calculates a moving average value of a first temperature detected by the first temperature detection element over a first period of time and uses the moving average value for output control of the DC power, and calculates a moving average value of a second temperature detected by the second temperature detection element over a second period of time and uses the moving average value for output control of the DC power, and the first period is shorter than the second period of time. Configuration 6: The wiring device for supplying DC power according to any one of configurations 1 to 5, wherein the control unit suppresses the maximum output power to a second maximum output power that is smaller than the first maximum output power when a first temperature detected by the first temperature detection element exceeds a first suppression temperature or when a second temperature detected by the second temperature detection element exceeds a second suppression temperature that is higher than the first suppression temperature. Configuration 7: The wiring device for supplying DC power described in Configuration 6, wherein the control unit stops outputting the DC power when the first temperature exceeds a third suppression temperature that is higher than the first suppression temperature, or when the second temperature exceeds a fourth suppression temperature that is higher than the third suppression temperature. Configuration 8: The wiring device for supplying DC power according to Configuration 6 or 7, wherein the control unit returns the maximum output power to the first maximum output power when, after the first temperature exceeds the first suppression temperature or the second temperature exceeds the second suppression temperature, the first temperature becomes equal to or lower than a first return temperature and the second temperature becomes equal to or lower than a second return temperature that is higher than the first return temperature. Configuration 9: The wiring device for supplying DC power according to any one of Configurations 1 to 8, wherein the control unit, when the first temperature or the second temperature increases, gradually reduces the maximum output power in accordance with the temperature, and, when the first temperature or the second temperature decreases, gradually increases the reduced maximum output power in accordance with the temperature, or returns the reduced maximum output power to the initial maximum output power before the reduction. Configuration 10: The wiring device for supplying DC power according to configuration 2 or 3, further comprising a heat dissipation member interposed between the power conversion component and an inner surface of the main body. Configuration 11: The wiring device for supplying DC power according to Configuration 10, wherein the main body is made of metal. Configuration 12: The wiring device for supplying DC power according to Configuration 10, wherein the main body is made of resin, and the heat dissipation member is a graphene sheet or a metal heat dissipation plate. [Explanation of symbols]

[0097] 1 power outlet 2. Wiring devices for supplying DC power (wiring devices) 2a,3a front 2b, 3b connection port 3 Power outlet device 4 decorative plates 4a opening 10 First board 11 Power conversion components 12 AC / DC conversion circuit 13 DC / DC converter 14 Detection circuit 15 Breaker 16 Communications Department 17 Memory section 20 Second board 21 terminals 22 first temperature detection element 23 Second temperature detection element 23a Element body 23b lead wire 24 Control Unit 30 Case 31 Power line 32 Bush 33 Heat dissipation material 40 Main Unit 41 First member 41a opening 41b Holding part 42 Second member 50 Cover 51 protrusion 100 Wall 101 Electronic equipment 102 USB connector 103 Cable

Claims

1. A wiring device to be installed in an embedded hole formed on a construction surface, a power conversion component that converts AC power into DC power; a terminal for outputting the DC power; a housing that accommodates the power conversion component and the terminal; a first temperature detection element configured to detect a temperature of a first portion of the housing that is close to the terminal; a second temperature detection element configured to detect the temperature of a second portion within the housing that is farther from the terminal than the first portion; a control unit that controls the DC power output from the terminal based on temperatures detected by the first and second temperature detection elements; A wiring device for supplying DC power.

2. the housing has a main body inserted into the embedding hole and a cover attached to the main body and exposed to the outside of the embedding hole, The wiring device for supplying DC power according to claim 1 , wherein the second temperature detection element detects a temperature of the main body.

3. The wiring device for supplying DC power according to claim 2 , wherein the first temperature detection element detects a temperature of the terminal.

4. The control unit a first temperature detected by the first temperature detection element is acquired for each first period and used for output control of the DC power; calculating an average value or a median value of the second temperature detected by the second temperature detection element during a second period, and using the average value or median value for controlling the output of the DC power; The wiring device for supplying DC power according to claim 1 , wherein the first period is shorter than the second period.

5. The control unit calculating a moving average value of a first temperature detected by the first temperature detection element during a first period, and using the moving average value for output control of the DC power; calculating a moving average value of the second temperature detected by the second temperature detection element during a second period, and using the moving average value for output control of the DC power; The wiring device for supplying DC power according to claim 1 , wherein the first period is shorter than the second period.

6. The wiring device for supplying DC power according to any one of claims 1 to 5, wherein the control unit suppresses the maximum output power to a second maximum output power smaller than the first maximum output power when a first temperature detected by the first temperature detection element exceeds a first suppression temperature, or when a second temperature detected by the second temperature detection element exceeds a second suppression temperature higher than the first suppression temperature.

7. 7. The wiring device for supplying DC power according to claim 6, wherein the control unit stops output of the DC power when the first temperature exceeds a third suppression temperature that is higher than the first suppression temperature, or when the second temperature exceeds a fourth suppression temperature that is higher than the third suppression temperature.

8. 7. The wiring device for supplying DC power according to claim 6, wherein the control unit returns the maximum output power to the first maximum output power when, after the first temperature exceeds the first suppression temperature or after the second temperature exceeds the second suppression temperature, the first temperature becomes equal to or lower than a first return temperature and the second temperature becomes equal to or lower than a second return temperature that is higher than the first return temperature.

9. The control unit When the first temperature or the second temperature increases, the maximum output power is reduced in stages according to the temperature; 7. The wiring device for supplying DC power according to claim 6, wherein, when the first temperature or the second temperature decreases, the maximum output power suppressed in accordance with the temperature is increased in a stepwise manner or is returned to the initial maximum output power before suppression.

10. The wiring device for supplying DC power according to claim 2 or 3, further comprising a heat dissipation member interposed between the power conversion component and an inner surface of the main body.

11. The wiring device for supplying DC power according to claim 10 , wherein the main body is made of metal.

12. The main body is made of resin, The wiring device for supplying DC power according to claim 10 , wherein the heat dissipation member is a graphene sheet or a metal heat dissipation plate.

Images