Ground fault interrupt and usb power supply electrical wiring device

Abstract

An electrical wiring device comprising: a ground fault interrupt assembly including a ground fault interrupt circuit formed on a first printed circuit board and a trip mechanism, the ground fault interrupt circuit configured to detect a differential current between a line conductor and a neutral conductor and trigger the trip mechanism to electrically separate a plurality of line terminals from a plurality of load terminals based at least in part on the differential current according to predetermined criteria; and a USB power supply circuit formed on a second printed circuit board disposed within a compartment, the USB power supply circuit provided to at least one USB port, wherein the first printed circuit board and the second printed circuit board are spaced apart by a distance within the interior compartment.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to U.S. Provisional Patent Application No. 62 / 930,185, filed November 4, 2019, and U.S. Provisional Patent Application No. 63 / 063641, filed August 10, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to cabling equipment, and more specifically, to ground fault interruption electrical cabling equipment with a USB power supply. Background Technology

[0004] The proliferation of mobile devices has created a widespread demand for readily available charging ports. Almost every mobile device can be charged with a charging cable that has a USB connector on one end and a micro-USB or Lightning connector on the other. Therefore, the need for readily available charging ports can be met by providing USB ports in electrical wiring fixtures.

[0005] This type of electrical equipment can be equipped with ground fault protection. There are several reasons why ground faults can occur. First, if the insulation of the electrical wiring in the load circuit is damaged, the live wire conductor may become grounded. This scenario represents a risk of electric shock. For example, if a user touches the live wire conductor while in contact with the ground, the user will be shocked. Ground faults can also occur when the equipment comes into contact with water. Damage to the insulation within the power distribution system can also lead to ground faults.

[0006] A ground fault creates a differential current between the live conductor and the neutral conductor. Under normal operating conditions, the current flowing in the live conductor should be equal to the current in the neutral conductor. Therefore, a GFCI (Ground Fault Circuit Interrupter) is typically constructed to compare the current in the live conductor with the return current in the neutral conductor by sensing the differential current between the two conductors. When the differential current exceeds a predetermined threshold (typically around 6mA), the GFCI usually responds by interrupting the circuit. Circuit interruption is typically achieved by disconnecting a set of contacts positioned between the power source and the load. A GFCI can also respond by actuating some kind of alarm.

[0007] However, the combination of ground fault interruption and the accompanying electromechanical components for disconnecting contacts requires considerable space within the electrical cabling equipment housing. Adding a USB power supply for powering the USB ports can result in a relatively large profile for the electrical cabling equipment. The electrical cabling equipment housing must remain within certain constraints to fit into a standard wall box and avoid taking up too much space within the wall.

[0008] However, a more compact approach to integrating USB power supplies with fault-tolerant circuitry exacerbates thermal management issues for both, as heat-generating components must be positioned close together to minimize the overall profile of the electrical wiring. More specifically, the various components of the USB power supply and fault-tolerant circuitry, such as bridge rectifiers, microcontrollers, or transformers (these are provided as example components only, as the included components may vary depending on the specific example of the USB power supply and fault-tolerant circuitry), generate a relatively large amount of heat. When these components are used together in a compact housing, the heat generated by each component can potentially overheat the electrical wiring.

[0009] Therefore, there is a need for a relatively compact ground fault interruption electrical wiring device with a USB charging port that manages the heat of both the USB power supply circuit and the ground fault interruption circuit. Summary of the Invention

[0010] The examples described in this article can be combined in any technically possible way.

[0011] According to one aspect, an electrical wiring device includes: a plurality of line terminals, the plurality of line terminals including a live line terminal and a neutral line terminal, wherein the plurality of line terminals are configured to be connected to an AC power distribution system; a plurality of load terminals, the plurality of load terminals including a live load terminal and a neutral load terminal; a line conductor electrically connecting the live line terminal to the live load terminal; a neutral conductor electrically connecting the neutral line terminal to the neutral load terminal; a live receptacle contact electrically contacting the live line terminal in a reset state and a neutral receptacle contact electrically contacting the neutral line terminal in the reset state, wherein the live receptacle contact and the neutral receptacle contact are sized and positioned to receive plug prongs of a load plug; and a Universal Serial Bus (USB) receptacle configured to receive USB. An adapter; a housing defining an inner compartment in which line conductors, a neutral conductor, a live wire socket contact, a neutral wire socket contact, and a USB socket are at least partially disposed; a ground fault interruption assembly disposed in the inner compartment, the ground fault interruption assembly including a tripping mechanism and a ground fault interruption circuit formed on a first printed circuit board, the ground fault interruption circuit being configured to detect a differential current between the line conductors and the neutral conductor and trigger the tripping mechanism to electrically disconnect a plurality of line terminals from a plurality of load terminals at least partially based on the differential current according to a predetermined criterion; and a USB power supply circuit formed on a second printed circuit board disposed in the inner compartment, the USB power supply circuit being supplied to the USB socket, wherein the first printed circuit board and the second printed circuit board are spaced apart by a distance in the inner compartment.

[0012] In the example, the electrical wiring equipment also includes a metal oxide rheostat that shares electrical contact with the ground fault interruption circuit and the USB power supply circuit to absorb voltage transients in the ground fault interruption circuit or the USB power supply circuit.

[0013] In the example, the leads of the metal oxide rheostat extend through the first printed circuit board to the second printed circuit board, or extend through the second printed circuit board to the first printed circuit board.

[0014] In the example, the ground fault interruption circuit is electrically insulated from the first printed circuit board by an insulating substrate disposed between the first printed circuit board and the second printed circuit board, wherein the insulating substrate is made of a material having a resistivity greater than that of ambient air.

[0015] In the example, a first surface of the insulating substrate is disposed adjacent to the USB power supply circuit, wherein at least one component of the USB power supply circuit is disposed within a recess in the insulating substrate, the recess being sized to receive the at least one component.

[0016] In the example, the second surface of the insulating substrate is disposed adjacent to the USB power supply circuit, wherein at least one component of the USB power supply circuit is disposed within a recess in the insulating substrate, the recess being sized to receive the at least one component.

[0017] In the example, the electrical wiring equipment also includes a second live wire socket contact that is in electrical contact with the live wire line terminal and a second neutral wire socket contact that is in electrical contact with the neutral wire line terminal.

[0018] In the example, the live wire socket contact is electrically contacted with the second live wire socket contact via a first fixed contact bridge extending between the live wire socket contact and the second live wire socket contact, wherein the neutral wire socket contact is electrically contacted with the second neutral wire socket contact via a second fixed contact bridge extending between the neutral wire socket contact and the second neutral wire socket contact, wherein the first fixed contact bridge and the second fixed contact bridge are respectively deflected toward the periphery of the housing, wherein at least one of the following—a USB socket printed circuit board, a USB socket, a ground fault interruption component, or a USB power supply circuit—on which the USB socket is fixed, is at least partially disposed between the first fixed contact bridge and the second fixed contact bridge.

[0019] In the example, the USB power supply circuit includes a transformer, wherein the second printed circuit board includes a first side and a second side, wherein the first side faces the ground fault interruption component, wherein the second side faces away from the ground fault interruption component, and wherein the transformer is disposed on the second side of the second printed circuit board.

[0020] In the example, each of the components of the USB power supply circuit is disposed on the second side.

[0021] In the example, the USB power supply circuit includes a controller and a bridge rectifier, wherein the controller is separated from the bridge rectifier by a distance of at least 15 mm.

[0022] In the example, the ground fault interruption component is disposed between the USB power supply circuit and the front cover, wherein the USB power supply circuit is electrically connected to the USB socket via a conductor wire extending through the ground fault interruption component and between the line conductor and the neutral conductor.

[0023] In the example, when the electrical wiring device is in a reset state, the USB power supply circuit makes electrical contact with the live wire load terminal and the neutral wire load terminal to receive power.

[0024] In the example, the USB power supply circuit is in electrical contact with the fire wire terminal and the neutral wire terminal.

[0025] In the example, the line conductor and the neutral conductor are made of a material with a conductivity of at least 35% IACS.

[0026] In the example, the line conductor and the neutral conductor are made of brass. Attached Figure Description

[0027] A more comprehensive understanding and appreciation of the present invention will be achieved by reading the following detailed embodiments in conjunction with the accompanying drawings, wherein:

[0028] Figure 1 This is a perspective view of a protection device with a ground fault interruption component and a USB power supply, based on an example.

[0029] Figure 2 This is an exploded view of a protection device with a ground fault interruption component and a USB power supply, based on an example.

[0030] Figure 3 This is an internal perspective view of a portion of a protection device with a ground fault interruption component and a USB power supply, based on an example.

[0031] Figure 4 This is an exploded view of the insulating substrate and USB PCB based on the example.

[0032] Figure 5 This is an internal perspective view of a portion of a protection device with a ground fault interruption component and a USB power supply, based on an example.

[0033] Figure 6 This is an internal perspective view of a portion of a protection device with a ground fault interruption component and a USB power supply, based on an example.

[0034] Figure 7 This is an internal side view of a protection device with a ground fault interruption component and a USB power supply, based on an example.

[0035] Figure 8 This is an internal perspective view of a portion of a protection device with a ground fault interruption component and a USB power supply, based on an example.

[0036] Figure 9 This is an internal perspective view of a portion of a protection device with a ground fault interruption component and a USB power supply, based on an example.

[0037] Figure 10 This is a schematic diagram of a ground fault interruption circuit based on the example.

[0038] Figure 11 This is a schematic diagram of a USB power supply circuit based on an example. Detailed Implementation

[0039] The various aspects of the examples, along with certain features, advantages, and details thereof, are explained more fully below with reference to the non-limiting examples shown in the accompanying drawings. Descriptions of well-known structures are omitted to avoid unnecessarily obscuring the details of the invention. However, it should be understood that the detailed descriptions and specific non-limiting examples, when indicating aspects of the invention, are given by way of illustration only and not as limitations. Various substitutions, modifications, additions, and / or arrangements based on the spirit and / or scope of the concepts of the invention will be apparent to those skilled in the art from this disclosure. A 15-amp protective cabling device is shown and described herein with respect to the illustrated embodiments. Embodiments of the invention are similarly applicable to 20-amp protective cabling devices (and other protective cabling devices identified herein), as should be understood and appreciated by those skilled in the art in conjunction with a review of this disclosure (i.e., the front cover and neutral-side contacts are structurally different; otherwise, embodiments of the invention are structurally and functionally identical).

[0040] Reference will now be made in detail to the present exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Where possible, the same reference numerals will be used throughout the drawings to refer to the same or similar parts. Various parts / elements of the protective device of embodiments of the invention are first identified hereinafter and illustrated in the drawings. Many parts / elements are conventional, as will be understood by those skilled in the art in conjunction with a review of this disclosure, and need not be discussed in further detail except as identified and indicated in certain drawings. The structure, construction, and positioning are unique and inventive relative to the function of other specific parts / elements / assemblies and / or other specific parts / elements / assemblies in the protective wiring device assembled as a whole. Such other parts / elements / assemblies will be described in further detail below, except as identified and indicated in certain drawings.

[0041] Examples of the protective wiring device of the present invention are as follows: Figure 1 As shown, and generally indicated by reference numeral 10. Figure 1A perspective view of an exemplary assembled protection device 10 is depicted, having multiple receptacles and a USB port, as well as multiple features to minimize the profile of the protection device 10 and manage heat generated by the USB power supply and ground fault interruption circuitry. These features will be described in detail in this disclosure. Many of these features can be implemented independently of each other (that is, to the extent technically possible, some examples of the protection device 10 may use some of these features instead of others). Furthermore, many of these features can be used to minimize the profile or manage heat in electrical wiring devices other than the protection device 10; in fact, many features can be used outside of electrical wiring devices having a ground fault interruption component and a USB power supply and USB port. For example, many of these features can be used in any ground fault interruption electrical wiring device (where the USB power supply and USB port are omitted), and similarly, many of these features can be used in any electrical wiring device having a DC (direct current) power supply and a charging port (not just a USB power supply and port). Moreover, although many of these inventive features are shown with a specific example of a ground fault interruption component, many of these features can be used in any suitable ground fault interruption component, as long as it is appropriate for the specific ground fault interruption component used.

[0042] Certain structural and functional aspects of embodiments of the present invention are similar to embodiments of a protective cabling device described and illustrated in U.S. Application No. 16 / 967331, filed August 4, 2020, entitled “Protective Cabling Equipment,” which is incorporated herein by reference in its entirety and generally describes many features of the functionality of the ground fault interruption components and the electrical cabling equipment. Detailed explanations have been omitted where such ground fault components or other features are identical to those of the protective equipment 10 to avoid unnecessarily obscuring the features of the invention, and their construction and operation should be described with reference to U.S. Application No. 16 / 967331. Furthermore, U.S. Application No. 16 / 967331 itself relies on various patents to interpret additional features. These patents are also incorporated herein by reference in their entirety for additional explanation and embodiments, and include: U.S. Patent Nos. 9,437,386, 9,543,715, and 9,893,456.

[0043] As shown in the figure, the protective device 10 includes a housing having a front cover 12, a rear body 14, and a separator 16, which together define an internal compartment. The front cover 12 includes receptacle holes 12-1, 12-2 configured to receive the live, neutral, and ground terminals of a wired plug, and USB ports 12-3, 12-4 configured to receive a USB plug (e.g., for charging a mobile device). The rear body 14 includes line screw terminals 102 and load screw terminals 202, which allow the device to be connected to an AC power supply and a load circuit accordingly.

[0044] Go to Figure 2 This shows an exploded perspective view of a protective device 10, an example of the present invention. Starting from the top of the device, various parts / components are now identified: test button 18, front cover 12, reset button 17, reset structure 17-1, reset disconnect spring 17-2, ground bus 2, USB socket PCB 303 on which type A USB socket 303-1 and type B USB socket 303-2 are mounted, live wire socket terminal 22-1 including live wire socket contact 22-10 and fixed contact bridge 22-12, neutral wire socket terminal 22-2 including neutral wire socket contact 22-20 and fixed contact bridge 22-22, light guide 204-3, separator 16, test contact arm 234, including The electromechanical components 200 (or “ground fault interruption assembly”) of the electromechanical PCB 201 and tripping mechanism 203 (which includes latch blocks 220 and latches 230), live wire line contact arm 104-1, neutral wire line contact arm 104-2, live wire line terminal 102-1, neutral wire line terminal 102-2, live wire load terminal arm 202-1, neutral wire load terminal arm 202-2, spacer 301 (or “insulating substrate”), USB printed circuit board 302, rear body 14 (which is elongated in this example to accommodate USB printed circuit board 302 and spacer 301), and assembly threaded part 5.

[0045] Figure 2 The exploded view also depicts alternative examples of the front cover 12: front cover 12' and front cover 12". Front cover 12' includes USB ports 12-3 and 12-4 for two Type A USB receptacles 303-1; while front cover 12" includes USB ports 12-3 and 12-4 for two Type C USB receptacles 303-2. Front cover 12' mates with the USB receptacle 303-2 of the USB printed circuit board 303'. Front cover 12" mates with the USB receptacle 303-1 of the USB printed circuit board 303".

[0046] Ground fault interrupt circuit 1000 (see below) Figure 10 (Brief description) Detects ground faults and, together with the tripping mechanism 203, electrically separates the live wire terminals 102-1 and 102-2 from the live wire load terminals 202-1 and 202-2, respectively. The ground fault interruption circuit 1000 is formed on the electromechanical PCB 201, and the tripping mechanism 203 is also mounted on the electromechanical PCB 201.

[0047] The USB power supply circuit 1100 converts the AC power voltage existing between the live wire terminal 102-1 and the neutral wire terminal 102-2 into the USB voltage supplied to the USB sockets 303-1 and 303-2 for powering connected devices. The USB power supply circuit 1100 (described below in conjunction with...) Figure 11 (Brief description) is formed on the USB PCB302. The USB PCB302 and the electromechanical PCB201 are disposed in the internal compartment of the housing (e.g., within the rear body 14).

[0048] Figure 3 A perspective view is depicted of the ground fault interruption assembly 200, the USB PCB 302, and the live wire contact arm 104-1, neutral wire contact arm 104-2, live wire terminal 102-1, neutral wire terminal 102-2, live wire load terminal arm 202-1, neutral wire load terminal arm 202-2, and spacer 301. As shown, the electromechanical PCB 201 is positioned at a distance D from the USB PCB 302. Distance D typically ensures electrical insulation between the ground fault interruption circuit 1000 and the USB power supply circuit 1100. To minimize the size of distance D, and thus the outline of the protection device 10, an insulating substrate 301 may be positioned between the electromechanical PCB 201 and the USB PCB 302. The insulating substrate 301 may be formed of any suitable material having a resistivity greater than that of ambient air, such as rubber or plastic, and therefore may be thinner than the width of the air gap required to insulate the ground fault interruption circuit 1000 from the USB power supply circuit 1100. In another alternative example, the electromechanical PCB 201 and the USB PCB 302 can be separated only by an air gap, instead of using an insulating substrate 301, although this would require a slightly larger profile to protect the device 10, since the air gap must be greater than the thickness of the insulating substrate 301 to ensure electrical insulation between the electromechanical PCB 201 and the USB PCB 302.

[0049] It should be understood that in some examples, some of which will be described below, there may be some electrical communication between the ground fault interruption circuit 1000 and the USB power supply circuit 1100 (e.g., supplying AC power voltage to the USB power supply circuit). Therefore, it should be understood that, for the purposes of this disclosure, maintaining electrical insulation between the ground fault interruption circuit 1000 and the USB power supply circuit 1100 requires preventing electrical contact between the respective circuits (other than connections designed to occur). In other words, the insulating substrate 301 is positioned to prevent unwanted electrical contact between the stacked components of the ground fault interruption circuit 1000 and the USB power supply circuit 1100.

[0050] like Figure 4As shown, to further minimize the distance D between the electromechanical PCB 201 and the USB PCB 302, the insulating substrate 301 may define one or more recesses in its surface for receiving one or more components of the electromechanical PCB 201 or the USB PCB 302, thereby allowing the electromechanical PCB 201 to be positioned closer to the USB PCB 302. For example, recesses 301-2 and 301-3 may be defined within other flat surfaces of the insulating substrate 301 to receive components such as jumpers and solder from the electromechanical PCB 201 at recess 301-3 or components such as diodes from the USB PCB 302 at recess 301-2. Figure 4 As shown. However, this is provided only as an example, and it should be understood that in various alternative examples, any number of recesses can respectively accommodate any number of any type of component to ensure that the electromechanical PCB201 is positioned as close as possible to the USB PCB302, while providing insulation between the respective circuits. Furthermore, as... Figure 4 As shown, the spacer 301 can be adapted to the USB PCB 302 via the snap-fit ​​fitting 301-6 to ensure that the spacer 301 and the USB power supply 302-1 are held together tightly.

[0051] Both the ground fault interruption circuit 1000 and the USB power supply circuit 1100 use metal oxide varistors (MOVs) to prevent transient voltages (i.e., voltage surges) that could otherwise damage the ground fault interruption circuit 1000 or the USB power supply circuit 1100. Because the MOV is a fairly large component, a single MOV can typically be shared between the ground fault interruption circuit 1000 and the USB power supply circuit 1100 to reduce the size of the ground fault interruption circuit and the USB power supply circuit 1100 (and thus reduce the overall profile of the protection device 10). In other words, a single MOV can typically be positioned between the live wire input terminal and the neutral wire input terminal of the ground fault interruption circuit 1000 and the USB power supply circuit 1100 to shunt current from each input terminal in the event of a transient voltage. This can be achieved by providing electrical contact between the live wire input of the ground fault interruption circuit and the USB power supply circuit and one lead of the MOV, and between the neutral wire input of the ground fault interruption circuit and the USB power supply circuit and the other lead of the MOV. In this way, excess current from voltage transients present in the AC power supply voltage will be shunt by the shared MOV of the ground fault interrupt circuit 1000 and the USB power supply circuit. (Brief Reference) Figure 10 and 11 In this example, Figure 10 MOV2 and Figure 11 MOV1 is implemented as the same component.

[0052] Back Figure 3 To electrically connect the same MOV204 to the ground fault interruption circuit 1000 and the USB power supply circuit 1100, leads 204-1 and 204-2 can be allowed to extend through the electromechanical PCB 201 to the USB PCB 302, or from the USB PCB 302 to the electromechanical PCB 201. Where the MOV204 leads are typically trimmed, when the MOV204 is soldered to the electromechanical PCB 201 or the USB PCB 302, the leads can be left untrimmed, traversing the distance D between the electromechanical PCB 201 and the USB PCB 302, allowing electrical contact with the ground fault interruption circuit 1000 and the USB power supply circuit 1100. For example, as... Figure 3 As shown, the MOV leads can extend through the through-holes 201-1 and 201-2 of the electromechanical PCB 201 at a distance D separating the electromechanical PCB 201 and the USB PCB 302 (e.g., ...). Figure 5 and 6 As shown), and passes through the through holes 302-1 and 302-2 of the USB PCB 302 (as shown). Figure 4 (As shown). This example can also be used for a dual purpose, namely, to provide power from the live and neutral terminals of the ground fault interruption circuit 1000 to the live and neutral terminals of the USB power supply circuit 1100. Additionally, the USB power supply circuit requires separate connections to the live and neutral input terminals (e.g., via tabs on the live and neutral input terminals). Furthermore, in this example, the apertures 301-4, 301-5 defined in the spacer 301 ( Figure 4 (As shown in the figure) can be further used to guide leads 204-1, 204-2 to USB PCB 302 and allow leads 204-1, 204-2 to pass through spacer 301 to reach USB PCB 302 (otherwise they would be blocked there).

[0053] Alternatively, in addition to the leads of the MOV204, separate conductors (e.g., wires) can be used to form a common electrical contact between the MOV204 and the ground fault interruption circuit 1000 and the USB power supply circuit 1100. For example, the MOV204 can be soldered to one of the ground fault interruption circuit 1000 and the USB power supply circuit 1100 and connected to the other via wires.

[0054] To further manage the heat generated by the various components of the USB power supply circuitry, at least one component of the USB power supply circuitry may be positioned on the side of the USB PCB 302 opposite to the electromechanical PCB 201. Figure 7In the example, certain components of the USB power supply circuit 1100 are located on the side of the USB PCB 302, specifically on the side facing away from the electromechanical PCB 201, designated 302B. This placement of the components in the USB power supply circuit 1100 is intended to manage the heat generated by these components by positioning the USB PCB 302 between the heat-generating components and the electromechanical PCB 201, thereby thermally insulating the components of the USB power supply circuit 1100 from the components of the ground fault interruption circuit 1000. Furthermore, this positioning of the components in the USB power supply circuit 1100 increases the distance between the components of the USB power supply circuit 1100 and the components of the ground fault interruption circuit 1000.

[0055] exist Figure 7 In the example, only certain components—such as those that generate the most heat—are located on side 302B. For example, transformer 1102 (in...) Figure 11 The component designated T1 can be positioned on side 302B along with various other components. However, as shown in the figure, other heat-generating components, such as bridge rectifier 1103 (in... Figure 11 Designated as BR1) and controller 1104 (in Figure 11 The components designated U1 are located on side 302A. These components are not positioned on side 302B to space them from the transformer 1002 and to better manage the spacing on the USB PCB 302, on which the surface area for positioning components is limited. In another example, all components of the USB power supply circuit 1100 are positioned on side 302B to space them from the components of the ground fault interrupt circuit 1000.

[0056] Similarly, some or all components of the ground fault interruption circuit 1000 may be located on the side 201A of the electromechanical PCB 201, opposite to the USB PCB 302. For example... Figure 6 As shown, some components of the ground fault interruption circuit 1000 face the USB PCB 302; however, in an alternative example, some or all of these components may be positioned on the opposite side of the electromechanical PCB 201 to increase the distance between the components of the USB power supply circuit 1100 and the components of the ground fault interruption circuit 1000, and to position the electromechanical PCB 201 as a thermal insulator.

[0057] Furthermore, components on individual sides of the USB PCB302 and electromechanical PCB201 can be spaced apart to distribute the generated heat across the PCB rather than concentrating it in one location. This can be seen, for example, by the relative positions of the bridge rectifier 1103 and the controller 1104, which are spaced apart on side 302A of the USB PCB302 to avoid concentrating the heat generated by each in a single location. In one example, the bridge rectifier 1103 and the controller 1104 can be spaced at least 15 mm apart to distribute the generated heat across the USB PCB302 (in the example, a distance of 20 mm is shown to effectively distribute the heat-generating components across the surface of the USB PCB302).

[0058] To further control heat, the various components of the protection device 10 may be made of a material with a thermal conductivity of at least 35% IACS. Such components may be, for example, the live wire terminal 102-1, the neutral wire terminal 102-2, the live wire contact arm 104-1, the neutral wire contact arm 104-2, the live wire load terminal arm 202-1, the neutral wire load terminal arm 202-2, and the jumper 201-3. The material may be, for example, 7025 brass (which has a conductivity of 40% IACS), although other materials are conceivable.

[0059] Now go to Figure 8 The perspective view of the protection device 10 shows the separator 16, the live wire socket terminal 22-1, and the neutral wire socket terminal 22-2. As shown, the live wire socket terminal 22-1 includes a fixed contact bridge 22-12, and the neutral wire socket terminal 22-2 includes a fixed contact bridge 22-22. The fixed contact bridge 22-12 provides electrical contact between the live wire socket contacts 22-10, and the fixed contact bridge 22-22 provides electrical contact between the neutral wire socket contacts 22-20. Therefore, by placing the live wire socket terminal 22-1 in electrical contact with the live wire line contact arm 104-1 (and the live wire load terminal arm 202-1), and by placing the neutral wire socket terminal 22-2 in electrical contact with the neutral wire line contact arm 104-2 (and the neutral wire load terminal arm 202-2), AC power supply voltage will exist between the live wire socket contact 22-10 and the neutral wire socket contact 22-20 as long as the protection device 10 is in the reset state. Once the protection device 10 enters the trip state and the tripping mechanism 203 interrupts the electrical contact between the live wire line contact arm 104-1 and the live wire socket terminal 22-1, and the electrical contact between the neutral wire line contact arm 104-2 and the neutral wire socket terminal 22-2, power supply to the live wire socket terminal 22-1 and the neutral wire socket terminal 22-2 will be stopped.

[0060] To further reduce the profile of the protection device 10, fixed contact bridges 22-12 and 22-22 can be deflected toward the sidewall of the rear body 14 (i.e., at an angle perpendicular to or inclined to axis AA), thereby allowing the USB socket PCB 303 (and thus USB sockets 303-1 and 303-2) to be disposed between the fixed contact bridges 22-12 and 22-22, and thus more deeply disposed within the rear body 14. In other words, by deflecting the fixed contact bridges 22-12 and 22-22 toward the sidewall of the housing—between the live wire socket contact 22-10 and the neutral wire socket contact 22-20—the fixed contact bridges 22-12 and 22-22 can be disposed on the side of the electromechanical assembly 200, and thus detract from the profile of the protection device 10. In the example shown, the deflected fixed contact bridges 22-12 and 22-22 can each be deflected toward the corresponding sidewall of the rear body 14, such that no other components are positioned between the deflected fixed contact bridges 22-12 and the sidewall of the rear body 14, or between the fixed contact bridges 22-22 and the sidewall of the rear body 14. In an alternative example, the electromechanical PCB 201 and / or the USB PCB 302 can be positioned between the deflected fixed contact bridges 22-12 and 22-22, rather than positioned to or also to the electromechanical USB socket PCB 303.

[0061] like Figure 9 As shown, the output voltage of the USB power supply circuit 1100 can be supplied to the USB sockets 303-1 and 303-2 via conductor wire 302-3. To further minimize space requirements, conductor wire 302-3 can be threaded between the live wire load terminal arm 202-1 and the neutral wire load terminal arm 202-2. Conductor wire 302-3 can be held in place via a hole 301-8 defined at the end of the spacer 301.

[0062] It should be understood that any suitable ground fault interruption circuit can be used to trigger the trip mechanism 203. For completeness, a brief description of an example ground fault interruption circuit 1000 is shown. The protection device 10 includes a differential transformer 1002 configured to sense load-side ground faults, i.e., ground faults located in the load connected to load terminals or socket contacts. Transformer 1004 is configured as a neutral grounding transmitter for detecting grounded neutral faults. The differential transformer 1002 and the neutral grounding transmitter 1004 are electrically connected to a fault detector U1. Detector U1 receives power from a half-wave rectifier diode D1, thereby inputting power to pin Vs 3 of detector U1, where it is further processed by internal regulating circuitry. The output of detector U1 is connected to the control input of SCR Q1. When SCR Q1 is ON, the solenoid coil K1A is energized to actuate the trip mechanism 203, causing trip mechanism 203 to open and switch K1B to close. The solenoid coil K1A remains energized for a period of time, typically less than approximately 25 milliseconds. When the trip mechanism 203 trips, the line terminals separate from their corresponding load terminals or socket contacts. The trip mechanism 203 can be reset by the reset button 17 after the fault condition has been cleared. The MCU (microcontroller) U2 provides additional functionality to monitor the detector U1. The MCU U2 is responsible for self-testing, miswiring detection, and status indication. Unlike the U1 detector, which only receives power and operates during the positive half-cycle, the MCU U2 has power and functionality throughout the entire line cycle (positive and negative). This is accomplished via the half-wave rectifier diode D4 and voltage regulators Q5, R5, D5, and C12, where C12 provides storage during the negative half-cycle. During the self-test via the test GFCI node, the microcontroller U2 controls FET Q2, whose drain is supplied with a positive DC voltage via multiple IOs through the MCU U2. Various other IOs of the MCU U2 are used for basic but necessary standard MCU practices such as zero-crossing (ZC) monitoring, system power availability via the RST node, programming nodes, etc. The following section will describe in detail some aspects of the MCU U2's self-test and miswiring tests, with appropriate reference to relevant patents. Other aspects of the MCU U2 are known and will not be explained in detail here.

[0063] The differential transformer 1002 includes a secondary winding connected to a fault detector U1, which is accompanied by noise filtering circuitry. The differential transformer 1002 senses the current difference between the live and neutral conductors and provides a sensor signal to the ground fault detector U1 via (IN-, IN+) inputs. When the differential current (sensor signal) exceeds a predetermined threshold, the fault detector U1 should set the SCR output to HIGH.

[0064] The neutral grounding transmitter 1004 is configured to detect a neutral grounding condition. (The line neutral conductor is typically grounded at the panel in the electrical circuit – this does not constitute a neutral grounding fault condition). The neutral transmitter 1004 is configured to couple the same signal to the live conductor, the neutral conductor, and the self-test (third conductor). Because the differential transformer 1002 is configured to sense the current difference, the same signals provided by the neutral grounding transmitter 1004 effectively cancel each other out. On the other hand, a neutral grounding condition occurs when the load neutral conductor (i.e., the conductor connected to the load neutral terminal or neutral socket contact) is accidentally grounded. This creates a parallel conductive path (relative to the neutral return path) between the neutral line terminal and the neutral load terminal. Therefore, another signal circulates around this current loop and couples to the neutral conductor (not the live conductor) to generate a differential current. Differential transformer 1002 senses the differential current between the live conductor and the neutral conductor, and detector U1 generates a fault detection signal to actuate SCR Q1, energizing solenoid K1A and tripping tripping mechanism 203.

[0065] Any suitable AC / DC power supply circuit can be used as a USB power supply circuit. An example of such a power supply circuit is... Figure 11 The circuit is shown as USB power supply circuit 1100. In this example, the input AC power supply voltage is received at terminals AC1 and AC2. USB power supply circuit 1100 converts this input voltage into a 5V output voltage at terminals 5V_IN and GND. This 5V output voltage is used as the bus voltage Vbus of the USB Type-A socket. This output voltage is provided only as an exemplary possible output voltage. In practice, various types of USB connectors are designed to supply different voltages, and therefore, in an alternative example, USB power supply circuit 1100 may be designed to supply a voltage consistent with the standard type of USB connector used in protection device 10. Alternatively, a separate output stage of DC / DC converter may be used to further regulate the output of USB power supply circuit 1100 to conform to the requirements of the type of USB socket used.

[0066] exist Figure 11In the example shown, the USB power supply circuit 1100 receives an AC power input signal, which is rectified and filtered via a bridge rectifier BR1, capacitors C20 and C3, and inductor L2. The rectified and filtered signal is input to transformer T1. Controller U1 (in one example, this controller is the power supply controller of the power integrated INN3165C) operates on the secondary side, sensing and regulating the feedback signal appearing at pin 3 via a voltage divider of R14 and R15. U1 contains an integrated switching device (such as a MOSFET). When controller U1 keeps the MOSFET ON, the current in the primary winding of transformer T1 increases. During this period, MOSFET Q1, controlled by controller U1, prevents current from flowing through the secondary winding of transformer T1. (MOSFET Q1 acts as a secondary-side rectifier. Typically, MOSFET Q1 is superior to a conventional diode because its turn-on voltage is much lower, resulting in less power loss and improved overall efficiency.) Once the controller turns the integrated MOSFET OFF, it simultaneously sets MOSFET Q1. From the moment the MOSFET is ON, the energy stored in the primary winding is transferred to the secondary winding of T1, which charges the output filter capacitor C14. (Capacitor C22 provides additional high-frequency attenuation.) Once the controller U1 turns the integrated MOSFET off again, the load current is supplied by the output filter capacitor C14. The integrated MOSFET, transformer T1, and MOSFET Q1 together form a variant of a flyback converter. A snubber circuit consisting of diode D1, resistor R6, capacitor C18, and resistor R21 effectively clamps the voltage and suppresses ringing on the MOSFET drain.

[0067] As described above, the output of the USB power supply circuit 1100 can be further modulated by combining various output stages to power Type-A or Type-C USB circuits. Furthermore, various controllers can be used as dedicated charging ports to communicate with connected devices. For example, in addition to the above, the Texas Instruments TPS2513A dedicated charging port controller can be used to monitor USB data voltage and automatically provide the correct electrical signature on the data line for charging.

[0068] As described above, the USB power supply circuit 1100 can receive power from the MOV typically shared between the ground fault interruption circuit 1000 and the USB power supply circuit 1100. Alternatively, tabs on the live wire line terminal 102-1 and the neutral wire line terminal 102-2 can make electrical contact with and supply power to the USB power supply circuit 1100. Both methods of supplying power to the USB power supply circuit 1100 place the USB power supply circuit 1100 in electrical contact with the line side of the protection device 10. This is generally expected because it ensures that high-frequency switching of the USB power supply circuit 1100 does not cause an obstructive tripping of the tripping mechanism 203. However, in an alternative example, the USB power supply circuit 1100 can receive power from the load side of the protective cabling device (e.g., from tabs located at the ends of the live wire load terminal arm 202-1 and the neutral wire load terminal arm 202-2). Although the USB power supply circuit 1100 is already an NEC Class 2 power supply, which provides acceptable protection against electric shock by supplying power to the USB power supply circuit 1100 from the load side, the USB power supply circuit 1100 and the subsequent USB socket will be disconnected from power in the event of a trip, thus providing a redundant protection method.

[0069] While an example of dual USB dedicated charging ports is described in this disclosure, it should be understood that the protection device 10 may include any number of USB ports. Furthermore, as mentioned above, various alternative examples may combine charging ports in addition to USB charging ports to utilize the features described herein. Additionally, some of the features described herein can be used to improve the profile dimensions or thermal management of devices that do not include power supply circuitry (e.g., GFCI-only protection devices) or devices that do not include ground fault interruption protection circuitry or mechanisms.

[0070] While several embodiments of the invention have been described and illustrated herein, those skilled in the art will readily conceive of various other means and / or structures for performing functions and / or obtaining results and / or one or more advantages described herein, and each such variation and / or modification is considered within the scope of the embodiments of the invention described herein. More generally, those skilled in the art will readily understand that all parameters, dimensions, materials, and structures described herein are to be exemplary, and actual parameters, dimensions, materials, and / or structures will depend on the specific application or multiple specific applications using the teachings of the invention. Those skilled in the art will recognize, or be able to determine, many equivalents of the embodiments of the particular invention described herein using only conventional experimentation. Therefore, it should be understood that the foregoing embodiments exist only by way of example and are within the scope of the appended claims and their equivalents; embodiments of the invention may be practiced in ways other than those specifically described and claimed.

[0071] All references cited in this article, including publications, patent applications and patents, are incorporated herein by reference to the same extent as each reference individually and specifically indicated by reference as is presented herein as a whole.

[0072] All definitions used herein should be understood to govern the general meaning of dictionary definitions, definitions in referenced and incorporated literature, and / or the terms used.

[0073] The use of the terms “a,” “an,” and “the,” as well as similar references, in the context of describing the invention (particularly in the context of the following claims) is to be construed as covering both the singular and the plural, unless otherwise stated herein or obviously contradicted by the context. Unless otherwise stated, the terms “comprising,” “having,” “including,” and “comprise” are to be construed as open-ended terms (i.e., meaning “including but not limited to”). The term “connected” is to be construed as being partially or wholly contained in, attached to, or linked together, even with the intervention of something else.

[0074] As used herein in the specification and claims, the phrase “at least one” relating to a list of one or more elements should be understood to mean at least one element selected from any one or more elements in the list of elements, but not necessarily including every single element specifically listed in the list of elements and at least one of all elements, and does not exclude any combination of elements in the list of elements. This definition also allows for the optional presence of elements other than those specifically identified in the list of elements referred to by the phrase “at least one,” whether related to or unrelated to those specifically identified elements. Thus, as a non-limiting example, “at least one A and B” (or, equivalently, “at least one A or B”, or equivalently, “at least one A and / or B”) in one embodiment may mean at least one, optionally including more than one A, with no B (and optionally including elements other than B); in another embodiment, it means at least one, optionally including more than one B, with no A (and optionally including elements other than A); in yet another embodiment, it means at least one, optionally including more than one A, and at least one, optionally including more than one B (and optionally including other elements); and so on.

[0075] It should also be understood that, unless the contrary is explicitly stated, in any method claimed herein that includes more than one step or action, the order of the steps or actions of the method is not necessarily limited to the order in which the steps or actions of the method are described.

[0076] The approximate language used throughout this specification and claims can be used to modify any quantitative representation that allows for changes without altering the essential function associated with it. Therefore, values ​​modified by one or more terms, such as “approximately” and “substantially,” are not limited to specific precise values. In at least some cases, approximate language may correspond to the precision of the instrument used to measure the value. Scope limitations may be combined and / or interchanged herein and throughout the specification and claims; unless otherwise indicated by context or language, these scopes are identified and include all subscopes contained therein.

[0077] Unless otherwise indicated herein, the description of numerical ranges herein is intended only as a way of referring to each individual value falling within the range individually, and each individual value is incorporated into the specification as if it were described separately herein.

[0078] All methods described herein may be performed in any suitable order unless otherwise indicated herein or clearly contradicted by the context. Any and all examples or exemplary language (e.g., “for example”) used herein are intended merely to better illustrate embodiments of the invention and not to limit the scope of the invention, unless otherwise required.

[0079] Nothing in the specification should be construed as indicating that any unclaimed element is essential to the practice of the invention.

[0080] In the claims and in the foregoing description, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “constituting,” etc., are understood to be open-ended, meaning including but not limited to. Only the transitional phrases “comprising” and “essentially constituting” should be closed or semi-closed transitional phrases, respectively, as described in Section 2111.03 of the U.S. Patent Examination Procedure Manual.

[0081] It will be apparent to those skilled in the art that various modifications and alterations can be made to the invention without departing from its spirit and scope. The invention is not intended to be limited to the disclosed one or more specific forms; rather, it is intended to cover all modifications, alternative structures, and equivalents falling within the spirit and scope of the invention as defined by the appended claims. Therefore, the invention is intended to cover modifications and alterations to the invention as long as they fall within the scope of the appended claims and their equivalents.

Claims

1. An electrical wiring device, comprising: Multiple line terminals, including live wire line terminals and neutral wire line terminals, wherein the multiple line terminals are configured to be connected to an AC power distribution system; Multiple load terminals, including live wire load terminals and neutral wire load terminals; A line conductor that electrically connects the live wire line terminal to the live wire load terminal; A neutral conductor that electrically connects the neutral line terminal to the neutral load terminal; A live wire socket contact that is electrically in contact with the live wire line terminal when in the reset state, and a neutral wire socket contact that is electrically in contact with the neutral wire line terminal when in the reset state, wherein the live wire socket contact and the neutral wire socket contact are sized and positioned as plug prongs for receiving load plugs. A Universal Serial Bus (USB) socket configured to receive a USB adapter; A housing defining an inner compartment, wherein the line conductors, neutral conductors, live wire socket contacts, neutral wire socket contacts, and universal serial bus sockets are at least partially disposed within the inner compartment. A ground fault interruption assembly disposed in the inner compartment includes a tripping mechanism and a ground fault interruption circuit formed on a first printed circuit board. The ground fault interruption circuit is configured to detect a differential current between the line conductor and the neutral conductor and trigger the tripping mechanism to electrically disconnect multiple line terminals from multiple load terminals, at least partially based on the differential current, according to predetermined criteria. A USB power supply circuit is formed on a second printed circuit board disposed in the inner compartment. The USB power supply circuit provides power to the Universal Serial Bus (USB) socket. The first and second printed circuit boards are spaced apart in the inner compartment. The ground fault interruption circuit is electrically insulated from the first printed circuit board by an insulating substrate disposed between the first and second printed circuit boards. The insulating substrate is made of a material having a resistivity greater than that of ambient air.

2. The electrical wiring device according to claim 1 further includes a metal oxide rheostat, wherein the metal oxide rheostat is in common electrical contact with the ground fault interruption circuit and the USB power supply circuit to absorb voltage transients in the ground fault interruption circuit or the USB power supply circuit.

3. The electrical wiring device according to claim 2, wherein, The leads of the metal oxide rheostat extend through the first printed circuit board to the second printed circuit board, or extend through the second printed circuit board to the first printed circuit board.

4. The electrical wiring device according to claim 1, wherein, The first surface of the insulating substrate is disposed adjacent to the USB power supply circuit, wherein at least one component of the USB power supply circuit is disposed within a recess in the insulating substrate, the recess being sized to receive the at least one component.

5. The electrical wiring device according to claim 4, wherein, The second surface of the insulating substrate is disposed adjacent to the USB power supply circuit, wherein at least one component of the USB power supply circuit is disposed within a recess in the insulating substrate, the recess being sized to receive the at least one component.

6. The electrical wiring device according to claim 1 further includes a second live wire socket contact that is electrically in contact with the live wire terminal when in the reset state and a second neutral wire socket contact that is electrically in contact with the neutral wire terminal when in the reset state.

7. The electrical wiring device according to claim 6, wherein, The live wire socket contact is electrically contacted with the second live wire socket contact via a first fixed contact bridge extending between the live wire socket contact and the second live wire socket contact. The neutral wire socket contact is electrically contacted with the second neutral wire socket contact via a second fixed contact bridge extending between the neutral wire socket contact and the second neutral wire socket contact. The first and second fixed contact bridges are respectively deflected toward the periphery of the housing. At least one of the following—a Universal Serial Bus (USB) socket printed circuit board, a USB socket, a ground fault interruption component, or the USB power supply circuitry mounted thereon—is at least partially disposed between the first and second fixed contact bridges.

8. The electrical wiring device according to claim 1, wherein, The USB power supply circuit includes a transformer, wherein the second printed circuit board includes a first side and a second side, wherein the first side faces the ground fault interruption component, wherein the second side faces away from the ground fault interruption component, and wherein the transformer is disposed on the second side of the second printed circuit board.

9. The electrical wiring device according to claim 8, wherein, Each of the components of the USB power supply circuit is disposed on the second side.

10. The electrical wiring device according to claim 1, wherein, The USB power supply circuit includes a controller and a bridge rectifier, wherein the controller and the bridge rectifier are separated by a distance of at least 15 mm.

11. The electrical wiring device according to claim 1, wherein, The ground fault interruption assembly is disposed between the USB power supply circuit and the front cover, wherein the USB power supply circuit is electrically connected to the Universal Serial Bus receptacle via a conductor wire extending through the ground fault interruption assembly and between the line conductor and the neutral conductor.

12. The electrical wiring device according to claim 1, wherein, When the electrical wiring device is in the reset state, the USB power supply circuit makes electrical contact with the live wire load terminal and the neutral wire load terminal to receive power.

13. The electrical wiring device according to claim 1, wherein, The USB power supply circuit is in electrical contact with the live wire terminal and the neutral wire terminal.

14. The electrical wiring device according to claim 1, wherein, The line conductor and the neutral conductor are made of a material having a conductivity of at least 35% IACS.

15. The electrical wiring device according to claim 14, wherein, The line conductor and the neutral conductor are made of brass.

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