Patent Application
20200006883
The present invention generally relates to safety protection of electrical power supply circuits, and more specifically to an electrical receptacle with a safety mechanism that can be used as part of an intelligent power supply circuit.
With advances in communications technology, the world is moving toward a connected society. Improvements in wireless network speed, coverage, and accessibility, as well as the pervasiveness of online connections, enable individuals to have ubiquitous access to information and services—anytime and anywhere. This mobile-centric approach has brought—and will continue to bring—significant changes in education, health care, transportation, energy, and entertainment.
Individuals can now use a variety of devices for ubiquitous access to these services, including smartphones, tablets, laptop computers, smart glasses, etc. Although these devices differ in form and function, all share the common feature of having a rechargeable battery as an energy source. As such, the ability to maintain ubiquitous access to online services is greatly dependent on the ability to recharge batteries of these electronic devices.
Furthermore, due to the increases in energy storage capacity/density of rechargeable batteries, various devices that traditionally included an AC power cord are now becoming battery-powers. For example, as lithium ion batteries have become more prevalent, many power tools used by professionals and/or tradespersons have become battery-powered. Much like the access devices discussed above, the value of these tools is greatly dependent on the ability to recharge the batteries whenever necessary.
Accordingly, vehicle manufactures today are providing DC-AC inverters and AC outlet sockets in vehicles as convenience features to facilitate vehicle-based operation and/or battery-charging for these electronic devices and/or tools. The AC outlet socket is the interface with the plug on the electronic device, which is also referred to herein as an “electrical receptacle.” This socket typically supplies AC electricity at voltages of 110V to 230V. A voltage of this value has the potential to cause hazard—including death—by electrocution to an individual exposed to it. To protect against this potential hazard, the electrically-conductive outlet terminals are usually contained within a non-conductive enclosure, thereby making it difficult for the user to come in contact with the conductive terminals.
However, the degree of difficulty depends on the design of the non-conductive enclosure. Often, this enclosure must be designed in multiple pieces and/or parts in order to facilitate assembly with the conductive terminals. In such case, it can be possible—even with some difficulty—for the user to remove an outer part of the enclosure such that the conductive terminals are exposed when the electrical socket is energized. As such, this leaves the user exposed to the hazard that the enclosure was intended to prevent.
Accordingly, to address at least some of such issues and/or problems, certain exemplary embodiments of methods, electrical receptacles, and/or power supply circuits according to the present disclosure can prevent the potential electrocution hazard discussed above, thereby facilitating safe use of AC electricity in vehicles. These improvements can facilitate adoption of AC electrical outlets in vehicles in a manner that is acceptable, desirable, and/or preferred by end users, manufacturers, and regulatory agencies.
Exemplary embodiments of the present disclosure include various embodiments of an electrical receptacle. In various embodiments, the electrical receptacle can include a base formed of electrically insulating material and arranged to hold at least one pair of electrically conductive terminals. In various embodiments, the electrical receptacle can also include a cover formed of electrically insulating material and configured to be joinable with the base. The cover can comprise a top portion having a bottom surface, and at least one separating tab attached to the bottom surface at an angle of approximately 90 degrees. Each separating tab can be arranged to separate two terminals comprising one of the pairs of electrically conductive terminals, only when the cover is at least partially joined with the base. In such embodiments, each separating tab can be arranged such that it does not separate two terminals when the cover is separated from the base.
In other embodiments, each separating tab can be arranged to separate the two terminals comprising one of the pairs of electrically conductive terminals only when the cover is fully joined with the base. In such embodiments, each separating tab can be arranged such that it does not separate two terminals when the cover is either partially joined with or separated from the base.
In some embodiments, the base can further comprise an inner portion arranged to hold the at least one pair of electrically conductive terminals, and an outer portion comprising four sides, wherein at least two of the sides comprise locking tabs. In some embodiments, each adjacent pair of sides of the base outer portion are joined at an angle of approximately 90 degrees.
In some embodiments, the cover can further comprise a side portion attached to the bottom surface of the top portion at an angle of approximately 90 degrees. The cover side portion can include four sides, at least two of which can comprise locking receptacles. The locking receptacles can be arranged to engage with the locking tabs when the cover and the base are fully joined. In some embodiments, the locking receptacles can be arranged to not engage with the locking tabs when the cover and the base are partially joined or separated.
In some embodiments, each adjacent pair of sides of the cover side portion are joined at an angle of approximately 90 degrees. In some embodiments, the cover top portion can comprise at least two apertures arranged such that, when the base and the cover are at least partially joined, each aperture is disposed above a corresponding one of the electrically conductive terminals. In some embodiments, the electrical receptacle can also include a source terminal coupled to a first terminal of each pair of electrically conductive terminals, and a fuse disposed between the source terminal and the respective first terminals.
Exemplary embodiments of the present disclosure also include various embodiments of a power supply circuit. In various embodiments, the power supply circuit can include a DC-AC inverter comprising an AC generation circuit. The power supply circuit can also include an electrical receptacle comprising a base and a cover, both of which can be formed of electrically insulating material. The cover can be configured to be joinable with the base, and vice versa. The base can be arranged to hold at least one pair of electrically conductive terminals that are electrically coupled to the DC-AC inverter.
The cover can comprise a top portion having a bottom surface and at least one separating tab attached to the bottom surface at an angle of approximately 90 degrees. In some embodiments, each separating tab can be arranged to separate two terminals comprising a particular pair of electrically conductive terminals, only when the cover is at least partially joined with the base. In other embodiments, each separating tab can be arranged to separate two terminals comprising a particular pair of electrically conductive terminals, only when the cover is fully joined with the base.
The power supply circuit can also include a protection circuit configured to prevent the DC-AC inverter from energizing the electrical receptacle when the power supply circuit is in an overload condition resulting from contact between two terminals comprising one of the pairs of electrically conductive terminals. In some embodiments, the protection circuit can be further configured to enable the DC-AC inverter to energize the electrical receptacle when the power supply circuit is in a normal operating condition. In some embodiments, the protection circuit can be further configured to prevent the DC-AC inverter from energizing the electrical receptacle when the power supply circuit is in a no-load condition.
In some embodiments, the protection circuit can be a fuse, which can be integral with the electrical receptacle. In some embodiments, the electrical receptacle can also include a source terminal coupled to an output of the AC generation circuit, and the fuse can be disposed between the source terminal and a first terminal of each pair of electrically conductive terminals.
In some embodiments, the protection circuit can be integral with the DC-AC inverter. In such embodiments, the protection circuit can comprise a load detection circuit configured to measure one or more parameters associated with the DC-AC inverter's AC output to the electrical receptacle. In such embodiments, the protection circuit can further comprise a processing circuit configured to compare the measured one or more parameters with corresponding first thresholds associated with the overload condition. The processing circuit can also be configured to, if the comparison with the first thresholds indicates an overload condition, perform at least one of the following: decouple the DC-AC inverter from a DC supply input, and disable the AC generation circuit. In some embodiments, the processing circuit can be further configured to generate a diagnostic trouble code (DTC) if the comparison with the first thresholds indicates an overload condition.
In some embodiments, the processing circuit can be further configured to compare the measured one or more parameters with corresponding second thresholds associated with the no-load condition. In such embodiments, the processing circuit can be further configured to, if the comparison with the second thresholds indicates a no-load condition, perform at least one of the following: decouple the DC-AC inverter from the DC supply input, and disable the AC generation circuit.
Various exemplary embodiments of the power supply circuit can comprise one or more electrical receptacles corresponding to any of the exemplary electrical receptacle embodiments described herein.
Exemplary embodiments of the present disclosure also include various methods and/or procedures for protecting a power supply circuit, comprising an electrical receptacle, against an overload condition. In various embodiments, the exemplary methods and/or procedures can include detecting an overload condition of the power supply circuit, the overload condition resulting from separation of a cover portion of the electrical receptacle from a base portion of the electrical receptacle. The exemplary methods and/or procedures can also include, in response to detecting the overload condition, performing at least one of the following: decoupling the power supply circuit from an energy source, and disabling an output of the power supply circuit that is coupled to the electrical receptacle.
In some embodiments, the exemplary methods and/or procedures can also include detecting a normal operating condition of the power supply circuit, the normal operating condition resulting from the cover portion and the base portion being at least partially joined. In such embodiments, the exemplary methods and/or procedures can also include, in response to detecting the overload condition, performing at least one of the following: coupling the power supply circuit to the energy source, and enabling the output of the power supply circuit.
These and other aspects, features, and advantages will become apparent upon reading the following detailed description of the exemplary embodiments of the present disclosure, when taken in conjunction with the appended claims.
Exemplary embodiments of the present disclosure can reduce, mitigate, and/or prevent the potential electrocution hazard discussed above, thereby facilitating safe use of AC electricity in vehicles. These improvements can facilitate adoption of AC electrical outlets in vehicles in a manner that is acceptable, desirable, and/or preferred by end users, manufacturers, and regulatory agencies. Existing and/or conventional approaches to electrical outlet safety typically rely on leaving the outlet (or receptacle) energized but blocking access to the openings (or apertures) for insertion of the plug terminals. These conventional approaches do not address the case where the receptacle cover (or faceplate) is removed, thereby exposing the user to a dangerous condition.
In contrast, embodiments of the present disclosure address this situation by causing the opposite terminals of the electrical receptacle to be electrically shorted when the receptacle is not fully assembled (e.g., a cover is removed from a base). The short condition can be removed—and the receptacle can become operational again—by reassembly (e.g., reattachment of the cover to the base), which reintroduces electrical isolation between the opposite terminals of the receptacle. Embodiments of the present disclosure can also include mechanisms for maintaining the receptacle in a fully-assembled condition, thereby making disassembly more difficult.
Embodiments of the present disclosure also provide advantages and benefits when such electrical receptacles are used in a power supply circuit that also includes a DC-AC inverter and a protection circuit. When the receptacle is disassembled causing the short between the opposite terminals, the protection circuit can detect a resulting overload condition and prevent the DC-AC inverter from energizing the receptacle with AC electricity. In embodiments where the protection circuit comprises a fuse, the fuse can also protect the DC-AC inverter from the overload condition, albeit at the expense of the fuse becoming permanently inoperable (i.e., until replaced). As such, the use of the novel electrical receptacles, disclosed herein, in such power supply circuits provides substantial safety benefits to various parties including end users, manufacturers of vehicle power supplies, and vehicle manufacturers.
As shown in
Top portion 110 also includes a plurality of apertures (e.g., holes), such as apertures 115a-e. The number, shapes, and layout of apertures 115a-e can be arranged for compatibility with terminals on various types of electrical plugs used in various countries and/or regions. In other words, different ones of apertures 115a-e can receive terminals from the various types of electrical plugs with which the cover 100 can be compatible.
Cover 200 comprises a top portion 210 and a side portion 230, which is represented in the cross-sectional view of
As shown in
As shown in
At least two of the sides 310a-d comprise locking tabs. In the exemplary embodiment shown in
Base 300 also includes an inner portion 330, which is arranged to hold the at least one pair of electrically conductive terminals. For example, inner portion 330 shown in
Terminals 340a-b can be formed in various shapes to support one or more different types of plug terminal arrangements used in various countries and/or regions. Moreover, receptacle terminals 340a-b can be formed in various shapes that can exert retention force and/or pressure on the inserted plug terminals. Terminals 340a-b also include protrusions 342a-b, respectively. As shown in the dashed circle of
Furthermore, as shown in
In the exemplary partially-joined arrangement shown in
In other exemplary embodiments (not shown), the electrical receptacle can be configured such that, in the partially-joined arrangement shown in
Power supply circuit 700 can include a DC-AC inverter 720 that receives current and voltage from DC source 710 and outputs AC current and voltage, e.g., via AC generation circuit 722. Power supply circuit 700 can also include a protection circuit 730, which is shown in
In various exemplary embodiments, each of receptacles 740 and 750 can comprise any of the electrical receptacles shown in, and described above in relation to,
In general, protection circuit 730 can enable DC-AC inverter 720 to energize receptacle(s) 740 and/or 750 when power supply circuit 700 is in a normal operating condition and prevent DC-AC inverter 720 from energizing the receptacle(s) when power supply circuit 700 is in an overload condition. For example, protection circuit 730 can be configured to protect power supply circuit 700 from various overload conditions that can occur with respect to receptacles 740 and/or 750. Such overload condition can result from contact between two opposite terminals (e.g., terminals 742, 744) of a pair comprising a receptacle (e.g., 740). As explained above, this contact can further result from the cover portion of a receptacle (e.g., 740) being separated from or partially joined with the base portion of the receptacle, depending on the particular embodiment. In some exemplary embodiments, protection circuit 730 can also prevent DC-AC inverter 720 from energizing the receptacle(s) when power supply circuit 700 is in a no-load condition.
The exemplary embodiments shown in
Fuses 830 and 835 can be configured to permanently open (e.g., “blow”) when the amount of current carried by the particular fuse exceeds an approximate, predetermined amount. As shown in
In some exemplary embodiments, each of fuses 830 and 835 can be integral with the associated receptacles 840 and 850, respectively. For example, receptacle 840 can include a source terminal 846 coupled to one output line of DC-AC inverter 820 (e.g., output of AC generation circuit 822), and fuse 830 can be disposed between source terminal 846 and terminal 842. Alternately, source terminal 846 can be coupled to the other output line of DC-AC inverter 820, with fuse 830 disposed between source terminal 846 and terminal 844. In such embodiments, once fuse 830 (835) blows, receptacle 840 (850) can become inoperable until replaced during service.
The exemplary embodiments shown in
Load detection circuit 924 can be configured to measure one or more parameters associated with the DC-AC inverter's AC output to receptacle 940 and (optionally) 950. In some embodiments, the one or more parameters comprise an AC current output and a load resistance associated with one or more of the receptacles. Load detection circuit 924 can provide the measured one or more parameters to processing circuit 926 (as illustrated by the arrow in
For example, processing circuit 926 can compare the measured current output against an overload current threshold and, in some cases, compare the measured load resistance against an overload resistance threshold. This comparison can indicate an overload condition in various ways. In some embodiments, an overload condition can be indicated by one of the parameters (e.g., current output) being greater than the corresponding threshold (e.g., overload current threshold). In some embodiments, an overload condition can be indicated by one of the parameters (e.g., load resistance) being less than the corresponding threshold (e.g., overload resistance threshold). In some embodiments, an overload condition can be indicated by a combination of parameters being greater than and/or less than corresponding thresholds.
Processing circuit 926 can be further configured to, if the comparison(s) indicate(s) an overload condition, perform at least one of the following operations: 1) disable AC generation circuit 922; and 2) decouple AC generation circuit 922 from DC source 910. This control by processing circuit 926 is illustrated by arrows in
In some exemplary embodiments, processing circuit 926 can be further configured to generate a diagnostic trouble code (DTC) if the comparison with the first thresholds indicates an overload condition. In some exemplary embodiments, processing circuit 926 can be further configured to prevent DC-AC inverter 920 from energizing receptacles 940 and 950 when the power supply circuit is in a no-load condition. In such exemplary embodiments, processing circuit 926 can be further configured to compare the measured one or more parameters with corresponding second thresholds associated with the no-load condition. This comparison can indicate a no-load condition in various ways.
In some embodiments, a no-load condition can be indicated by one of the parameters (e.g., current output) being less than the corresponding threshold (e.g., no-load current threshold). In some embodiments, a no-load condition can be indicated by one of the parameters (e.g., load resistance) being greater than the corresponding threshold (e.g., no-load resistance threshold). In some embodiments, a no-load condition can be indicated by a combination of parameters being greater than and/or less than corresponding thresholds. Processing circuit 926 can be further configured to, if the comparison(s) indicate(s) a no-load condition, perform at least one of the following operations: 1) disable AC generation circuit 922; and 2) decouple AC generation circuit 922 from DC source 910. Processing circuit 926 can be configured to perform such operations in a similar manner as discussed above with respect to a detected overload condition.
More generally, processing circuit 926 can comprise one or more digital processors that are operably connected to at least one memory, e.g., a program memory and a data memory. Program memory can store executable instructions (e.g., software, code, program, etc.) that, when executed by the processor(s), facilitates, causes, and/or configures processing circuit 926 to perform the operations discussed above and/or any of the exemplary methods and/or procedures described below. In some embodiments, the program memory can also include executable instructions that, when executed by the processor(s), facilitate, cause, and/or configure processing circuit 926 to perform other functions associated with power supply circuit 900. Data memory can comprise an area usable to store variables, tables, and/or other information used in such operations.
Moreover, any program memory and/or data memory comprising processing circuit 926 can include non-volatile memory (e.g., flash memory), volatile memory (e.g., static or dynamic RAM), or a combination thereof. Persons of ordinary skill in the art will recognize that processing circuit 926 can comprise multiple individual processors (including, e.g., multi-core processors), each of which can implement a portion of the functionality described above. In such cases, multiple individual processors can be commonly connected to program memory and/or data memory, or individually connected to multiple individual program memories and/or data memories. More generally, persons of ordinary skill in the art will recognize that processing circuit 926 can be implemented in many different computer arrangements comprising different combinations of hardware and software including, but not limited to, application processors, signal processors, general-purpose processors, multi-core processors, ASICs, and fixed and/or programmable digital circuitry.
The exemplary method and/or procedure shown in
The exemplary method and/or procedure shown in
In some embodiments, the exemplary method and/or procedure shown in
In some embodiments, the exemplary method and/or procedure shown in
Notably, modifications and other embodiments of the disclosed invention(s) will come to mind to one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention(s) is/are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of this disclosure. Although specific terms may be employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
