POWER SUPPLY WIRING CONNECTORS

Abstract

The invention relates to a wiring device (2) providing power supply comprising: a housing containing a circuit and socket connector; a control unit; and a moisture detection unit. The circuit has a voltage conversion circuit comprising a transformer, and a power output circuit applying the voltage after voltage conversion to the connector side corresponding to the connection of the switch. The moisture detection unit detects the presence of moisture inside the guide element and / or in the housing at the outside of the guide element. When a moisture detection signal is input from the moisture detection unit, the control unit controls the switch and transformer so that the switch is disconnected or the voltage applied to the secondary side is maintained at a minimum value set in advance in the state in which the switch is connected.

Description

Wiring devices that supply power

[0001] The present disclosure relates to a wiring device that supplies power, such as a wiring device that includes a USB (Universal Serial Bus) terminal.

[0002] Conventionally, USB outlets have been widely used as wiring devices for supplying DC power to electronic devices such as smartphones, tablet devices, and laptop computers. A wiring device for supplying power, such as a USB outlet, includes a circuit board on which electronic components are mounted, terminals for outputting DC power, and a housing surrounding the circuit board and terminals. The electronic components may include, for example, a power conversion component for converting AC power to DC power and an output circuit component for outputting the DC power from the terminals. The electronic components may also include an output circuit component for outputting voltage-converted AC power from the terminals. These electronic components may be distributed across multiple circuit boards or may be mounted on a single circuit board. Terminals for outputting power are connected to the upper side of the circuit board on which the output circuit component is mounted. The wiring device also includes a receptacle connector having a cylindrical guide portion and terminals inside the guide portion. The receptacle connector guides a plug connector for connecting a terminal inserted from outside to the terminal using the guide portion.

[0003] Furthermore, Patent Documents 1 and 2 disclose a wiring device in which a cover is provided on the outside of the wiring device so as to cover an insertion port into which a plug connector is inserted.

[0004] JP 2014-44914 A Japanese Patent No. 6491231 A

[0005] When the wiring device is installed on a top panel of a fixture or the like, an insertion port through which the plug connector can be inserted from above may be provided at the top of the wiring device so that the plug connector can be inserted from above and connected to the terminal. The insertion port may be provided at the top of the housing or at the upper end of the guide part of the receptacle connector, both of which open upward.

[0006] However, in wiring devices with an insertion port facing upward, if a container containing a liquid containing moisture falls onto the top surface of the top plate, the liquid may enter the housing through the insertion port and penetrate into the electronic components on the circuit board inside the housing. If power is applied in this state, problems such as malfunction of the electronic components may occur.

[0007] In some cases, the circuitry placed inside the housing includes a transformer that converts a primary voltage to a secondary voltage and outputs the converted voltage from the power output circuit to the terminals of the receptacle connector. In such cases, liquids are likely to seep into the power output circuit, which is likely to be placed near the receptacle connector, and applying a high voltage to this circuit increases the likelihood of malfunctions in the electronic components of that circuit.

[0008] In addition, in a conventional power output circuit where a switch is provided and voltage is output from the transformer to the terminals by connecting the switch, the control unit may control the switch to connect only when the plug connector is connected to the receptacle connector. In this case, even if liquid does not enter the power output circuit, if liquid enters the guide portion of the receptacle connector, current tends to flow between the two contact pins of the terminals through the liquid. As a result, a high current continues to flow through the power output circuit when the plug connector is connected, causing electronic components to heat up.

[0009] For this reason, in wiring devices having receptacle connectors that open upward, it is desirable to prevent high voltage from occurring when moisture adheres near the circuits located near the receptacle connector, and to suppress heat generation in electronic components when the plug connector is connected.

[0010] One aspect of the present disclosure is a wiring device for supplying power, which includes a housing that houses a circuit and a receptacle connector, a control unit, and a moisture detection unit. The receptacle connector has a bottomed, cylindrical guide portion that opens upward and a terminal that is located inside the guide portion and outputs power. The circuit has a voltage conversion circuit that converts the primary side voltage to the secondary side voltage using a transformer, and a power output circuit that applies the converted voltage to the terminal side by connecting a switch. The moisture detection unit detects moisture present inside at least one of the guide portion and the outer portion of the guide portion within the housing. The control unit connects the switch when a plug connector is connected to the receptacle connector, and when a moisture detection signal is input from the moisture detection unit, the control unit either disconnects the switch or controls the switch and the transformer so that the voltage applied to the secondary side is maintained at a predetermined minimum voltage. This is a wiring device for supplying power.

[0011] According to the present disclosure, in a configuration having a receptacle connector that opens upward, when moisture is detected inside the receptacle connector or on at least one of the exterior portions of the receptacle connector, the switch is turned off or the voltage applied to the secondary side when the switch is connected is maintained at a preset minimum voltage. This prevents high voltage from occurring when moisture adheres to the power output circuit located near the receptacle connector, which is prone to the intrusion of liquids containing moisture. Furthermore, when the plug connector is connected, it prevents a constant high current from flowing through the power output circuit via moisture inside the receptacle connector. This reduces heat generation in the electronic components of the power output circuit.

[0012] 1 is a perspective view showing a state in which an outlet using a wiring fixture for supplying power according to a first embodiment is in use; FIG. 2 is a perspective view showing the appearance of a wiring fixture for supplying power according to a first embodiment; FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2; FIG. 4 is a schematic view of the inside of a guide portion of a receptacle connector according to the first embodiment, viewed from above; FIG. 5 is a diagram showing a circuit disposed within a housing according to the first embodiment, showing a state in which a plug connector is not connected; FIG. 6 is a diagram showing a circuit disposed within a housing according to the first embodiment, showing a state in which a plug connector is connected and a switch is turned off upon moisture detection; FIG. 7 is a diagram showing a circuit disposed within a housing according to the first embodiment, showing a state in which a plug connector is connected and a switch is turned on upon moisture detection, so that the voltage applied to the secondary side is maintained at a predetermined minimum voltage; and FIG. 8 is a diagram corresponding to FIG. 6 for explaining an inconvenience of a wiring fixture according to a comparative example.

[0013] Hereinafter, an example of an embodiment of a wiring device for supplying 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.

[0014] [First embodiment] A wiring device 2 for supplying power according to a first embodiment will be described in detail with reference to Figures 1 to 5. Figure 1 is a perspective view showing a state in which an outlet 1 incorporating the wiring device 2 is in use. Note that, although the following describes a wiring device 2 for supplying DC power as a wiring device for supplying power, the wiring device of the present disclosure can also be a wiring device for supplying AC power.

[0015] As shown in Figure 1, outlet 1 is a wiring device including two wiring devices 2 for supplying DC power and one power outlet device 3, and is installed on a desk top 100, which is a piece of furniture. In this state, an insertion opening 2b for inserting a plug connector 102, which is provided in a housing (described later) constituting each wiring device 2, opens upward. At this time, a cylindrical guide portion with a bottom of a receptacle connector (described later) constituting each wiring device 2 opens upward and is configured to guide plug connector 102 to a terminal provided inside the guide portion.

[0016] The outlet 1 has a decorative plate 4 with three openings 4a formed in a horizontal row, and has a structure in which the upper surfaces 2a, 3a of the wiring device 2 and the power outlet device 3 are exposed through the three openings 4a of the decorative plate 4.

[0017] The decorative plate 4 has a rectangular shape when viewed from the front, and conceals the mounting holes formed in the top panel 100 and the mounting frame installed around the holes. 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 by, for example, hooking tabs formed on its back surface into the holes in the metal plate.

[0018] The outlet 1 is installed with the wiring device 2 and the power outlet device 3 inserted into a construction hole formed in the top plate 100. On the top surface of the outlet 1, only top surfaces 2a, 3a of the wiring device 2 and the power outlet device 3 are exposed through an opening 4a in the decorative plate 4. As will be described in detail later, the wiring device 2 includes electronic components such as a power conversion component that converts AC power to DC power, and a receptacle connector including a terminal that outputs the DC power, and is installed on the top plate 100 with the insertion opening 2b facing upward.

[0019] 1 , two wiring devices 2 are disposed adjacent to each other. In the outlet, the relative positions of the wiring devices 2 and the power outlet devices 3 are not particularly limited, and the number of wiring devices 2 is also not particularly limited. Furthermore, the outlet equipped with the wiring device 2 may be equipped with an optical outlet, a LAN outlet, a telephone line outlet, etc. instead of the power outlet devices 3, or may be equipped with only the wiring device 2.

[0020] 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 a direction perpendicular to the longitudinal direction of the slot-shaped insertion port 2b of the wiring device 2. The up-down direction is a direction along the vertical direction, and the left-to-right direction is a direction perpendicular to the up-down direction and the front-to-rear direction. In this example, the up-down direction is the direction in which the plug connector 102 is inserted into and removed from the wiring device 2. Furthermore, the up-down direction refers to the up-down direction when the wiring device is in use, and does not restrict the direction when the wiring device is not in use, such as when it is assembled.

[0021] An example of the wiring device 2 is a USB outlet device. The USB outlet device is a device to which a plug connector 102, which is a USB connector, can be connected, includes a power conversion component that converts AC power to DC power, and supplies DC power to an electronic device 101 such as a smartphone. In FIG. 1 , the plug connector 102 of a cable 103 extending from the electronic device 101 is connected to the wiring device 2. In this embodiment, the wiring device 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. Two insertion ports 2b for the wiring device 2 and an insertion port 3b for the power outlet device 3 are provided side by side in the left-right direction on the top surface of the outlet 1.

[0022] 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 , the outlet 1 including the wiring apparatus 2 is installed on the tabletop 100, but the wiring apparatus 2 may also be installed on furniture such as shelves, countertops, and beds, or on vehicles such as automobiles, airplanes, and railroad cars.

[0023] Fig. 2 is a perspective view showing the appearance of the wiring fixture 2, and Fig. 3 is a cross-sectional view taken along line A-A in Fig. 2. In Figs. 2 and 3, the front-rear direction of the wiring fixture 2 is indicated by X, the left-right direction by Y, and the up-down direction by Z.

[0024] 2 and 3 , the wiring device 2 includes a housing 10 that forms the external shape of the device, and includes a lower housing 20 and an upper housing 30. The wiring device 2 has an external shape that is generally rectangular parallelepiped, with the vertical length greater than the horizontal length greater than the front-to-rear length. However, the relationship between the vertical length, horizontal length, and front-to-rear length of the wiring device 2 is not limited to this.

[0025] The housing 10 has internal spaces 70 and 71 that house the primary circuit board 40, secondary circuit board 50, and receptacle connector 52, respectively, shown in Figure 3. The internal space of the housing is divided into two internal spaces 70 and 71 by a partition 24 and a sealing member 72. For example, the sealing member 72 is an elastic member such as rubber or a thermoplastic elastomer, and is compressed so as to fill the gap between the partition 24 and the inner surface of the housing. This prevents liquid from entering the internal space below the partition 24, even if water or other liquid enters the upper internal space.

[0026] The housing 10 is composed of a lower housing 20 having a cylindrical peripheral wall portion 21 and a bottom portion 22 that closes the lower end of the peripheral wall portion 21, and an upper housing 30 that is assembled and fixed to the lower housing 20 so as to cover the upper end.

[0027] The lower housing 20 has a rectangular box shape with an open top and a closed bottom. The upper housing 30 is separably fixed to the lower housing 20 by a fitting structure. As a result, the upper housing 30 and the lower housing 20 are assembled in a predetermined assembly direction corresponding to the up-down direction during use. Therefore, the lower housing 20 and the upper housing 30 are separably integrated along the predetermined assembly direction to form the housing 10. At least one of the lower housing 20 and the upper housing 30 may be formed by connecting two members separated in the front-rear or left-right direction of the housing 10. In this case, after the two members are connected, they are assembled to the other members constituting the housing in a predetermined assembly direction. For example, the lower housing may be formed by connecting two members separated in the front-rear or left-right direction, and after the two members are connected to form the lower housing, the lower housing and the upper housing are assembled in a predetermined assembly direction.

[0028] The lower housing 20 and the upper housing 30 may be fixed by a snap-fit ​​structure. The snap-fit ​​structure is configured, for example, such that when the lower housing 20 and the upper housing 30 are fixed together, a pair of fixing pieces extend from both ends in the left-right or front-rear direction of one of the lower housing 20 and the upper housing 30 toward the outer surface of the other member, and protrusions protruding from the outer surface of the other member are engaged with openings formed in each fixing piece, thereby sandwiching and fixing the other member between the pair of fixing pieces.

[0029] An insertion opening 2b for inserting a plug connector 102 for terminal connection is formed so as to penetrate vertically through the top of upper housing 30. The surface of upper housing 30 forms upper surface 2a of wiring device 2 in outlet 1. That is, wiring device 2 is fixed to the mounting frame of outlet 1 so that the surface of upper housing 30 having insertion opening 2b is exposed through opening 4a of decorative plate 4.

[0030] The wiring device 2 also includes a primary circuit board 40 mounted with electronic components including power conversion components that convert primary-side voltage to secondary-side voltage and convert AC power to DC power, a receptacle connector 52 that outputs DC power, and two upper and lower secondary circuit boards 50a, 50b mounted with electronic components including output circuit components that output DC power.

[0031] 3, primary circuit board 40 includes printed circuit board 41 and electronic components, including power conversion components, arranged on printed circuit board 41. Secondary circuit boards 50a and 50b include printed circuit boards 51a and 51b and electronic components, including output circuit components, arranged on printed circuit board 51a. Receptacle connector 52 is a USB terminal that is connected to the upper side of printed circuit board 51b of lower secondary circuit board 50b and is mounted on printed circuit board 51b.

[0032] The two secondary circuit boards 50 a, 50 b are electrically connected to each other and include an outer annular secondary circuit board 50 a arranged so as to surround the receptacle connector 52 in the internal space 70 inside the housing 10, and a secondary circuit board 50 b arranged in a central position in the left-right direction.

[0033] In this example, the secondary circuit board is divided into two, upper and lower. This allows electronic components that are likely to fail due to water intrusion, such as electrolytic capacitor 90, to be placed on the upper secondary circuit board 50a, while the lower end of receptacle connector 52 can be connected to the lower secondary circuit board 50b. Therefore, even if liquid containing moisture seeps into the vicinity of the outer periphery of receptacle connector 52, water intrusion into the electronic components included in the upper secondary circuit board 50a can be prevented. In the following description, secondary circuit boards 50a and 50b will be collectively referred to as secondary circuit board 50 as needed.

[0034] The printed circuit boards 41, 51 of each board 40, 50 are arranged in a direction perpendicular to the up-down direction Z. The lower housing 20 surrounds the printed circuit board 41 of the primary circuit board 40 and the electronic components arranged on the printed circuit board 41, the printed circuit boards 51a, 51b of the secondary circuit boards 50a, 50b and the electronic components arranged on the printed circuit board 51b, and the lower end of the receptacle connector 52. The upper housing 30 surrounds the upper end of the receptacle connector 52.

[0035] In this wiring device 2, the insertion opening 2b opens upward, and in the receptacle connector 52 described below, a cylindrical guide portion 53 that guides the plug connector 102 to the terminal 54 also opens upward. This makes it easy for liquid containing moisture to enter the housing 10 inside the insertion opening 2b when a container falls over on the top plate 100. This makes it easy for moisture to adhere to circuits near the receptacle connector 52 inside the housing 10. Moisture also easily enters the guide portion 53 of the receptacle connector 52. For this reason, if moisture adheres to the power output circuit 120 described below, which is a circuit that is often located near the receptacle connector 52, and a high voltage is applied, there is a high possibility that malfunctions will occur in the electronic components of that circuit. The power output circuit 120 is provided on the secondary circuit boards 50a and 50b. Furthermore, as will be described later, if a switch is provided in the power output circuit 120 and the voltage of the power output circuit 120 is output to the terminal 54 by connecting the switch when the plug connector 102 is connected, a high current will continue to flow through the power output circuit 120, which will cause the electronic components to heat up.

[0036] In this embodiment, to solve this problem, a moisture detection unit 80 (see FIG. 5 described later) that detects moisture present inside the guide unit 53 and / or the portion outside the guide unit 53 within the housing 10, and a control unit 110 (see FIG. 5 described later) are provided. When a moisture detection signal is input from the moisture detection unit 80, the control unit 110 controls the switch and the transformer 43 provided on the primary circuit board 40 so as to open the switch or, with the switch closed, to maintain the voltage applied to the secondary side at a predetermined minimum voltage. This will be described in detail below.

[0037] Each component of the wiring device 2 will be described in detail below with reference to FIGS. 2 to 5 as appropriate. [Primary Circuit Board] As shown in FIG. 3 , the primary circuit board 40 is a printed wiring board including electronic components arranged on a printed circuit board 41. The primary circuit board 40 is a power supply circuit that converts AC power supplied from an external commercial power source 104 into DC current and outputs the DC current to the receptacle connector 52 of the secondary circuit board 50. The primary circuit board 40 also includes a voltage conversion circuit 130 that converts a primary-side voltage to a secondary-side voltage. The voltage conversion circuit 130 is configured by electrically connecting power conversion components via wiring formed on and inside the printed circuit board 41. The primary circuit board 40 is provided with terminals that are connected to the commercial power source 104. The voltage conversion circuit 130 has a primary-side circuit A1, which is the commercial power connection side of a transformer 43 described below. The primary-side circuit A1 is connected to a secondary-side circuit A2 via the transformer 43, as described below.

[0038] The primary circuit board 40 includes a semiconductor element 42, a transformer 43, a common mode coil (not shown), an electrolytic capacitor, and the like, which are broadly defined power conversion components that constitute the voltage conversion circuit 130. Examples of the semiconductor element 42 include a switching element, a diode, and a transistor. In FIG. 3 , the semiconductor element 42 and the transformer 43 are arranged on the first surface (top surface in FIG. 3 ) of the printed circuit board 41, but the semiconductor element 42 may also be arranged on the second surface (bottom surface in FIG. 3 ) of the printed circuit board 41, and the arrangement of the electronic components is not limited thereto. The transformer 43 is used to step down the voltage of the secondary side circuit A2 from the voltage of the primary side circuit A1.

[0039] The primary circuit board 40 may be fixed to the inner surface of the lower housing 20 via a member not shown. For example, the primary circuit board 40 may be fixed to the lower housing 20 in a state in which heat dissipation members made of a highly thermally conductive material are sandwiched between both ends in the left-right direction Y of the printed circuit board 41 of the primary circuit board 40 and the inner surface of the lower housing 20. This makes it possible to improve the heat dissipation of electronic components mounted on the primary circuit board 40 when the lower housing 20 is made of a material with high heat dissipation properties, such as metal.

[0040] [Secondary Circuit Board] Secondary circuit boards 50a, 50b are printed wiring boards including a power output circuit 120 arranged on printed circuit boards 51a, 51a, and a receptacle connector 52, which will be described later, is mounted and connected to the power output circuit 120. The secondary circuit board 50 is electrically connected to the primary circuit board 40. The power output circuit 120 has the function of outputting DC power converted by the voltage conversion circuit 130 of the primary circuit board 40 to the receptacle connector 52.

[0041] Secondary circuit board 50b is fixed to the upper surface of plate-shaped partition 24 that protrudes in a direction perpendicular to the up-down direction from the inner surface of lower housing 20. The circuits of primary circuit board 40 and secondary circuit board 50b are connected by a plurality of wires 106 that pass through vertical holes provided in partition 24. Secondary circuit board 50a and secondary circuit board 50b are connected by a plurality of wires 107.

[0042] The lower end of the receptacle connector 52 is connected to the upper side of the secondary circuit board 50b, and electronic components such as an electrolytic capacitor 90, a semiconductor element 91, and a secondary-side control unit 92 are arranged on the secondary circuit board 50a. The secondary-side control unit 92 is, for example, a secondary-side control IC.

[0043] The receptacle connector 52 is connected to the upper surface of the printed circuit board 51b. The receptacle connector 52 is a USB terminal to which the plug connector 102 can be connected, and is formed in a generally flat, cylindrical shape. The type of USB terminal is not particularly limited. The receptacle connector 52 has a guide portion 53 that is cylindrical and has a bottom and opens upward, and the plug connector 102 is arranged at the back of the guide portion 53 in a state where it can be inserted and removed.

[0044] [Lower Housing] Lower housing 20 is a housing that houses primary circuit board 40 and secondary circuit board 50, and is not exposed on the top surface of outlet 1. Lower housing 20 is made of a resin such as melamine resin, urea resin, or ABS resin. Lower housing 20 may also be made of a metal such as aluminum or an aluminum alloy.

[0045] The lower housing 20 has a generally rectangular shape when viewed from above, and the lower end of a cylindrical peripheral wall 21 is closed by a bottom 22. The bottom 22 is formed with a hole 25 for allowing a power line 105 connecting a commercial power source 104 and the primary circuit board 40 to extend outside the housing 10. The position of the hole 25 is not limited in the lower housing 20. A cylindrical thin wall 21a with a rectangular cross section protrudes upward along the entire periphery from the inner periphery of the upper end of the peripheral wall 21. The lower end of an upper housing 30 (described below) is fitted and fixed into the thin wall 21a.

[0046] Upper housing 30 is a housing that houses the upper portion of receptacle connector 52, and is fixed to the upper side of lower housing 20. An insertion port 2b having a generally oval or other long hole shape that extends in the left-right direction is formed in the center of the upper end of upper housing 30 so as to penetrate in the up-down direction.

[0047] As described above, the upper end surface of the upper housing 30 where the insertion opening 2 b is formed becomes the upper surface 2 a of the wiring accessory 2 exposed on the upper surface of the outlet 1 .

[0048] The upper housing 30 has a generally rectangular shape when viewed from above, and is a stepped rectangular tube having an upper end wall 31 that is a generally rectangular plate that is long in the left-right direction and step portions 32 that are joined to both left and right ends of the upper end wall 31. The insertion opening 2b is not limited to a horizontally elongated shape that is long in the left-right direction, but may also be a vertically elongated shape that is long in the front-to-rear direction. In this case, the outer peripheral shape of the receptacle connector 52 is also a vertically elongated shape that is long in the front-to-rear direction.

[0049] A cylindrical thin wall portion 33a with a rectangular cross section protrudes downward along the entire periphery from the outer periphery of the lower end of the peripheral wall portion 33 of the upper housing 30. The thin wall portion 33a is fitted and fixed to the outer periphery of the thin wall portion 21a at the top of the lower housing 20. The upper housing 30 is fixed to the upper side of the lower housing 20, thereby forming a housing 10 that houses a receptacle connector 52 and a circuit 200, which will be described later. The circuit 200 includes a voltage conversion circuit 130 and a power output circuit 120, as will be described later.

[0050] The upper housing 30 is made of, for example, resin. Like the lower housing 20, the resin that constitutes the upper housing 30 is not particularly limited, but examples include urea resin, melamine resin, and ABS resin.

[0051] [Receptacle Connector] The receptacle connector 52 is connected to the upper side of the secondary circuit board 50 and outputs DC power. Specifically, the receptacle connector 52 includes a cylindrical guide portion 53 with a bottom and terminals 54 arranged inside the guide portion 53 and outputting DC power. The guide portion 53 guides the plug connector 102 for connection to the terminals 54 from above to the terminals 54. The guide portion 53 allows the plug connector 102 to be inserted and removed in the vertical direction. The guide portion 53 has a cylindrical shape whose cross section perpendicular to the vertical direction is an oval or the like that is elongated in the horizontal direction. The guide portion 53 has a shape that allows the cylindrical shell (not shown) of the plug connector 102 to fit inside. Therefore, if the shell has a cylindrical rectangular cross section, the guide portion 53 also has a cylindrical rectangular cross section.

[0052] Guide portion 53 may be provided with a locking mechanism that locks the shell in accordance with a predetermined standard to which receptacle connector 52 conforms. Guide portion 53 is formed of metal or resin. No through-holes that penetrate the inside and outside of guide portion 53 are formed in the outer peripheral surface of guide portion 53. Note that small holes that penetrate the inside and outside of guide portion 53 may be formed in the outer peripheral surface of guide portion 53, but it is preferable to form the small holes at a position higher than the bottom surface of the recess formed on the inside of guide portion 53 in order to make it difficult for liquid that has entered inside to escape to the outside of guide portion 53.

[0053] 4 is a schematic diagram of the inside of guide portion 53 of receptacle connector 52 as viewed from above. Terminal 54 may be configured according to a predetermined standard to which receptacle connector 52 complies. With the shell of plug connector 102 mated with guide portion 53, multiple pins 150, 151, 152, 153, and 154, which are multiple contacts of terminal 54, are electrically connected to multiple pins, which are multiple contacts housed in the shell of plug connector 102. Multiple pins 150, 151, 152, 153, and 154 of terminal 54 are connected to the circuit of secondary circuit board 50 via wiring. As a result, DC power is output from secondary circuit board 50 to electronic device 101 via terminal 54 and plug connector 102. In addition, in the terminal structure of FIG. 4, the multiple pins are arranged symmetrically with respect to the front-rear direction X and the left-right direction Y so that even if the plug connector 102 is inserted inverted with respect to the front-rear direction X of the guide portion 53, the multiple pins are connected to the terminal 54 so as to be able to output power to the plug connector 102.

[0054] The multiple pins 150, 151, 152, 153, and 154 include power transmission pins 150 and 151, two dead pins 152 and 153 that are not used for power transmission, and an output voltage request pin 154. The two dead pins 152 and 153 constitute a moisture detection unit 80 (see FIG. 5 ), which will be described later. FIG. 4 schematically shows that a resistance R1 between the inner ends of the guide portions 53 of the dead pins 152 and 153 is measured by a resistor R1 connected to the two dead pins 152 and 153.

[0055] 3, the upper end of guide portion 53 of receptacle connector 52 is in contact with or closely faces the open end of insertion opening 2b of housing 10 on the internal space 70 side. This makes it difficult for liquid that has entered insertion opening 2b from above to enter internal space 70 outside guide portion 53 directly without passing through the inside of guide portion 53.

[0056] 5 is a diagram showing a circuit 200 disposed inside the housing 10, showing a state in which the plug connector 102 is not connected. The circuit 200 has a voltage conversion circuit 130 provided on the primary circuit board 40 and a power output circuit 120 provided on the secondary circuit board 50. The voltage conversion circuit 130 has a transformer 43 and converts an AC voltage on the primary side into an AC voltage on the secondary side. In addition, a diode is connected to the secondary side of the voltage conversion circuit 130 as a semiconductor element 42. As a result, voltage-converted DC power is output from the voltage conversion circuit 130 side to the power output circuit 120.

[0057] A primary-side control unit 93 that constitutes a control unit 110 (described later) is provided on the primary circuit board 40. In Fig. 5, as an example, the primary-side control unit 93 changes a voltage of 100 V on the primary side to a voltage of 5 V on the secondary side.

[0058] The power output circuit 120 provided on the secondary circuit board 50 has an electrolytic capacitor 90 and a switch S1. The switch S1 may be formed, for example, from the semiconductor element 91 shown in FIG. 3. When the switch S1 is connected, the power output circuit 120 outputs the voltage converted by the voltage conversion circuit 130 to the terminal 54. When the plug connector 102 is connected to the terminal 54, power is output to the plug connector 102 using a power transmission pin 150 connected to the positive bus B1 of the power output circuit 120 and a power transmission pin 151 connected to the negative bus B2.

[0059] A secondary-side control unit 92 (to be described later) that constitutes the control unit 110 is provided on the secondary circuit board 50. The secondary-side control unit 92 controls the primary-side control unit 93 and switches the switch S1 between on and off.

[0060] [Moisture Detection Unit] A moisture detection unit 80 is also provided within the housing 10. The moisture detection unit 80 includes a moisture detection circuit 81 provided on the secondary circuit board 50 and two dead pins 152, 153 connected to the moisture detection circuit 81 via wiring. The two dead pins 152, 153 form a first detection unit C1 that detects moisture present inside the guide portion 53. The first detection unit C1 measures a resistance R1 between the inner ends of the two dead pins 152, 153 on the guide portion 53. When there is no moisture in the guide portion 53, the resistance R1 is, for example, infinite. However, when moisture enters the guide portion 53, the resistance R1 becomes a low resistance value other than infinite. Thus, by measuring the resistance R1, the first detection unit C1 can detect moisture present inside the guide portion 53.

[0061] A second detection unit C2 is provided outside the guide unit 53 between the two dead pins 152, 153 and the moisture detection circuit 81. The second detection unit C2 detects moisture present in the portion outside the guide unit 53 within the housing 10. In this case, as with the first detection unit C1, the second detection unit C2 can detect moisture present outside the guide unit 53 by measuring the resistance R2 between the portions of the two dead pins 152, 153 outside the guide unit 53.

[0062] For example, the second detection unit C2 can be configured to detect the presence of moisture in a position that is prone to flooding, such as the top surface of the printed circuit board 51b or a position lower than the top surface of the printed circuit board 51, in order to make it easier to detect the presence of moisture in the internal space 70 at an early stage when a liquid containing moisture begins to accumulate.

[0063] The moisture detection circuit 81 detects the presence of moisture in one or both of the first and second detection units C1 and C2 when the corresponding detection unit detects a decrease in resistance compared to normal conditions when no moisture is present. This allows the moisture detection unit 80 to detect moisture present inside the guide unit 53 and / or the outer portion of the guide unit 53 within the housing 10. The moisture detection unit 80 also detects the presence of moisture based on a change in resistance between the two dead pins 152 and 153. When the moisture detection unit 80 detects the presence of moisture, it outputs a moisture detection signal G to the secondary-side control unit 92. Figure 5 shows a water-containing liquid 180 that has seeped into the guide unit 53 due to a sandy area within the guide unit 53.

[0064] [Control Unit] A control unit 110 is also provided within the housing 10. The control unit 110 has a secondary-side control unit 92 provided on the secondary circuit board 50 and a primary-side control unit 93 provided on the primary circuit board 40. The secondary-side control unit 92 controls the switch S1 to close when the plug connector 102 is connected to the receptacle connector 52. At this time, as shown in FIG. 5 , the secondary-side control unit 92 determines that an output voltage request pin 154, which is one of the multiple pins of the terminal 54, is connected to a pin of the plug connector 102.

[0065] Furthermore, when the secondary-side control unit 92 receives a moisture detection signal from the moisture detection circuit 81, it outputs an OFF command to the switch S1 to shut off the switch S1, or outputs an ON command to the switch S1 to keep the switch S1 connected, and controls the switch S1 and the transformer 43 to maintain the voltage applied to the secondary side at a preset minimum voltage. Here, the "preset minimum voltage" refers not only to the voltage itself, but also to a voltage that can be said to be the minimum voltage at which conduction is possible without failure even when submerged in water, and refers to a set value whose operation has been guaranteed in advance through experiments, etc. Whether the control unit 110 shuts off the switch S1 or maintains the voltage applied from the power output circuit 120 to the terminal 54 at the preset minimum voltage with the switch S1 connected can be preset in the control unit 110.

[0066] 5 shows a case where the control unit 110 turns off the switch S1. Furthermore, because the plug connector 102 is not connected to the receptacle connector 52, no voltage request is output from the output voltage request pin 154 to the secondary-side control unit 92. Since the switch S1 is turned off at this time, even if moisture adheres to an electronic component of the power output circuit 120, high voltage is prevented from being applied to the circuit including that electronic component. Furthermore, even if moisture accumulates in the guide portion 53, a high current is prevented from continuously flowing through the power output circuit 120 when the plug connector 102 is connected, as shown in FIG. 6 (described later). This suppresses heat generation in the electronic components.

[0067] Furthermore, when the secondary-side control unit 92 receives a moisture detection signal from the moisture detection circuit 81, it controls the switch S1 to output an OFF command to the switch S1. At the same time, it outputs a command signal to the primary-side control unit 93 to maintain the secondary-side voltage at a preset minimum voltage, such as 5 V, and controls the transformer via the primary-side control unit 93. This minimum voltage may or may not be the same as the predetermined voltage required of the primary-side control unit 93 when the switch S1 is connected. This causes the primary-side control unit 93 to control the transformer 43 to output a low voltage, such as 5 V, to the secondary side. Therefore, the primary-side control unit 93 and the secondary-side control unit 92 can continue to operate by drawing this low-voltage power from wiring (not shown) even after the switch S1 is turned off. This allows the secondary-side control unit 92 and the primary-side control unit 93 to return to their pre-moisture detection operation when the moisture detection signal is no longer output from the moisture detection unit 80, and to output a normal high voltage, such as 20 V DC, to the plug connector 102 when the plug connector 102 is connected.

[0068] FIG. 6 is a diagram showing circuit 200 disposed within housing 10, illustrating a state in which plug connector 102 is connected and switch S1 is turned off upon moisture detection. In this case, plug connector 102 is connected to receptacle connector 52, so output voltage request pin 154 is connected to pin 160 of plug connector 102, and a predetermined voltage request, such as 20 V, is output from output voltage request pin 154 to secondary-side control unit 92. Even in this case, secondary-side control unit 92 controls switch S1 to be turned off upon input of moisture detection signal G, and outputs a command signal to primary-side control unit 93 instructing it to convert to a low voltage, such as 5 V, thereby controlling transformer 43 via primary-side control unit 93. As a result, even when plug connector 102 is connected, as in the case of FIG. 5, even if moisture adheres to an electronic component of power output circuit 120, high voltage can be prevented from being applied to the circuit including that electronic component. Furthermore, even if moisture accumulates inside the guide portion 53, it is possible to prevent a high current from continuously flowing through the power output circuit 120 regardless of the connection of the plug connector 102. This makes it possible to suppress heat generation in electronic components.

[0069] FIG. 7 is a diagram showing a circuit disposed within the housing 10, illustrating a case where the plug connector 102 is connected, and the switch S1 is closed upon moisture detection, maintaining the voltage applied to the secondary side at a predetermined minimum voltage. In the case shown in FIG. 7 , when a moisture detection signal is input from the moisture detection circuit 81, the secondary-side control unit 92 outputs an ON command to the switch S1 to close the switch S1 and control the transformer 43 so that the voltage applied to the secondary side is maintained at a predetermined minimum voltage. For example, in the case shown in FIG. 7 , as in the case of FIG. 6 , a voltage request of 20 V is output from the output voltage request pin 154 to the secondary-side control unit 92 upon connection of the plug connector 102. However, even in this case, since the moisture detection signal G is input to the secondary-side control unit 92, the secondary-side control unit 92 controls the switch S1 to be closed, but controls the transformer 43 via the primary-side control unit 93 to output a voltage of 5 V to the primary-side control unit 93, which is lower than the 20 V voltage output before moisture detection. 5, even if moisture adheres to the electronic components of the power output circuit 120, high voltage can be prevented from being applied to the circuit including the electronic components. Furthermore, even if moisture accumulates in the guide portion 53, high current can be prevented from continuously flowing through the power output circuit 120 regardless of whether the plug connector 102 is connected. This suppresses heat generation in the electronic components.

[0070] [Effects] According to the wiring device 10 of this embodiment, in a configuration including a receptacle connector 52 that opens upward, when moisture is detected in at least one of the receptacle connector 52 and the exterior of the receptacle connector 52, the switch S1 is turned off, or the voltage applied to the secondary side when the switch S1 is turned on is maintained at a preset minimum voltage. This prevents high voltage from occurring when moisture adheres to the power output circuit 120, which is located near the receptacle connector 52 and into which liquids containing moisture are likely to penetrate. Furthermore, when the plug connector 102 is connected, it prevents a high current from continuously flowing through the power output circuit 120 via moisture in the receptacle connector 52. This reduces heat generation in the electronic components of the power output circuit 120.

[0071] In this example, the terminal 54 has power transmission pins 150, 151 and two dead pins 152, 153 that are not used for power transmission, and the moisture detection unit 80 detects the presence of moisture based on a change in resistance between the two dead pins 152, 153. This eliminates the need to provide a dedicated moisture detection unit for detecting the presence of moisture in the guide portion 53, separate from the pins of the terminal 54, within the guide portion 53, thereby reducing the number of parts and costs. Note that the terminal 54 may have three or more dead pins that are not used for power transmission.

[0072] 8 is a diagram corresponding to FIG. 6 for explaining the disadvantages of a wiring device 220 of the comparative example. The wiring device 220 of the comparative example does not include a moisture detection unit 80 ( FIG. 5 ). Furthermore, a control unit 110a including a secondary-side control unit 92a and a primary-side control unit 93 controls switch S1 to be closed when plug connector 102 is connected to receptacle connector 52, and controls transformer 43 via primary-side control unit 93 to convert the voltage to 20 V in response to a signal representing a requested voltage output of 20 V input from output voltage request pin 154.

[0073] In this comparative example, for example, if liquid 180 containing moisture seeps into and accumulates in guide portion 53 of receptacle connector 52, as shown by the sandy area, current is likely to flow between two power transmission pins 150, 151 of terminal 54 via the liquid. As a result, a high current continues to flow through power output circuit 120 when plug connector 102 is connected, causing electronic components to heat up. This embodiment can prevent such a problem.

[0074] Furthermore, in the comparative example, even if a liquid containing moisture enters the housing 10 outside the guide portion 53, the switch S1 remains connected, and the voltage is not converted to the preset minimum voltage by the transformer 43. This causes a high voltage to be applied to the power output circuit 120, which may cause malfunctions in the electronic components of that circuit. This embodiment can also prevent such inconveniences.

[0075] 1 to 7, a control unit may be provided in the moisture detection circuit 81, and when moisture is detected by the moisture detection circuit 81, the control unit may control the switch S1 and the transformer 43 so that the switch S1 is turned off or the voltage applied to the secondary side is maintained at a preset minimum voltage value with the switch S1 turned on. In this case, the parts of the moisture detection circuit other than the control unit constitute the moisture detection unit.

[0076] In the above embodiment, the secondary-side control unit 92 is provided on the secondary circuit board 50, and the primary-side control unit 93 is provided on the primary circuit board 40, but both control units 92, 93 may be provided on either the secondary circuit board 50 or the primary circuit board 40. In this case, the secondary-side control unit 92 and the primary-side control unit 93 may be integrated to form a single control unit. Conversely, the control unit may be configured to be made up of three or more control units connected to each other.

[0077] The configurations of the present disclosure described above are as follows: (Configuration 1) A wiring device for supplying power, comprising: a housing that accommodates a circuit and a receptacle connector; a control unit; and a moisture detection unit, wherein the receptacle connector has a bottomed, cylindrical guide portion that opens upward and has a terminal that outputs power and is located inside the guide portion, the circuit has a voltage conversion circuit that converts a primary voltage to a secondary voltage using a transformer, and a power output circuit that applies the converted voltage to the terminal side by connecting a switch, the moisture detection unit detects moisture present inside the guide portion or in an area inside the housing that is outside the guide portion, and the control unit connects the switch when a plug connector is connected to the receptacle connector, and when a moisture detection signal is input from the moisture detection unit, controls the switch and the transformer to either disconnect the switch or maintain the voltage applied to the secondary side at a preset minimum voltage value with the switch connected. (Configuration 2) The power wiring device according to Configuration 1, wherein the terminal has a power transmission pin and at least two dead pins not used for power transmission, and the moisture detection unit detects the presence of moisture based on a change in resistance between the two dead pins. (Configuration 3) The power wiring device according to Configuration 1 or 2, wherein the control unit, when the moisture detection signal is input from the moisture detection unit, turns off the switch and controls the switch and the transformer to maintain the secondary side voltage at a predetermined voltage lower than normal. (Configuration 4) The power wiring device according to any one of Configurations 1 to 3, which supplies DC power. (Configuration 5) The power wiring device according to Configuration 4, which is a USB outlet device.

[0078] 1 Outlet, 2, 220 Wiring device (wiring device) for supplying power, 2a, 3a Top surface, 2b Terminal side insertion port, 2c Housing side insertion port, 3b Insertion port, 3 Power outlet device, 4 Decorative plate, 4a Opening, 10 Housing, 20 Lower housing, 21 Peripheral wall portion, 22 Bottom, 24 Partition portion, 29 Bottom member, 30 Upper housing, 31 Upper end wall portion, 33 Peripheral wall portion, 40 Primary circuit board, 41, 51 Printed circuit board, 42 Semiconductor element, 43 Transformer, 50, 50a, 50b Secondary circuit board, 51, 51a, 51b Printed circuit board, 52 Receptacle connector, 53 Guide portion, 54 Terminal, 70, 71 Internal space, 72 Sealing member, 80 Moisture detection portion, 81 Moisture detection circuit, 90 Electrolytic capacitor, 91 Semiconductor element, 92 Secondary side control unit, 93 Primary side control unit, 100 Top plate, 101 Electronic device, 102 Plug connector, 103 Cable, 104 Commercial power supply, 105 Power line, 106, 107 Wiring, 110, 110a Control unit, 120 Power output circuit, 130 Voltage conversion circuit, 150, 151 Power transmission pin, 152, 153 Free pin, 154 Output voltage request pin, 160 Pin, 180 Liquid, 200 Circuit.

Claims

1. A wiring device for supplying power, comprising: a housing for accommodating a circuit and a receptacle connector; a control unit; and a moisture detection unit, wherein the receptacle connector has a bottomed, cylindrical guide portion that opens upward and has a terminal arranged inside the guide portion and outputs power, the circuit has a voltage conversion circuit that converts a primary voltage to a secondary voltage using a transformer, and a power output circuit that applies the converted voltage to the terminal side by connecting a switch, the moisture detection unit detects moisture present inside the guide portion or in at least one of the guide portion and an outer portion of the guide portion within the housing, and the control unit connects the switch when a plug connector is connected to the receptacle connector, and cuts off the switch when a moisture detection signal is input from the moisture detection unit, or controls the switch and the transformer so as to maintain the voltage applied to the secondary side at a preset minimum voltage value with the switch connected.

2. A wiring device for supplying power as described in claim 1, wherein the terminal has a power transmission pin and at least two free pins not used for power transmission, and the moisture detection unit detects the presence of moisture based on a change in resistance between the two free pins.

3. A wiring device for supplying power as described in claim 1, wherein the control unit, when the moisture detection signal is input from the moisture detection unit, cuts off the switch and controls the switch and the transformer so as to maintain the secondary side voltage at a predetermined voltage lower than normal.

4. The wiring device for supplying power according to claim 1, which supplies DC power.

5. The wiring device for supplying power according to claim 4, which is a USB outlet device.

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