Patent Application
20130309908
This disclosure relates to power tips for power adaptors.
Consumer electronics and other electronic devices often need electrical power to power the device and/or charge one or more batteries. These electronic devices may include computers, laptops, tablets, mobile telephones, smart phones, personal digital assistants (“PDAs”), personal media players, and the like. Electronic devices require that electrical power comply with electrical requirements of the device. Electronic devices may require that the electrical power be supplied as direct current (“DC”), that a voltage between the terminals is within one or more predetermined ranges, and a certain current level be supplied. Because most power sources, such as household outlets, automobile and other vehicle outlets, and the like, are alternating current (“AC”) or are at a voltage outside the predetermined range, a power adaptor is needed to convert electricity from the power source such that it complies with the electrical requirements of the electronic device.
If the electronic device receives electrical power that does not comply with the electrical requirements, it may damage the electronic device. Electronic devices have physically distinct electrical input ports to prevent a potentially damaging connection with a power source not meeting the electronic devices' electrical requirements. Conventional power adaptors are generally designed to satisfy the electrical requirements of a single electronic device. These power adaptors are only designed to interface with the electrical input port for that particular electronic device.
Instead, a programmable power adaptor may be programmed to adapt to the electrical requirements of a plurality of electrical devices. This may involve manual selection by a user or an automatic determination of the electrical requirements. Alternatively, a power adaptor may be designed to output electrical power at a voltage and current that meets the requirements of the electrical requirements of multiple electronic devices. Such universal power adaptors should also be able to physically interface with input ports of the electronic devices. The power adaptors may have an intermediate output connector that interfaces with variably sized power tips. Each power tip is designed to physically and electrically couple with an input port of an electronic device through a device interface and to physically and electrically couple with the intermediate output connector through an adaptor interface. The power tips are further designed to electrically couple the input port with the power adapter via the intermediate output connector. In some embodiments, the programmable power adaptor may automatically determine the electrical requirements of the input port based on the power tip connected to it.
Because of the large variety of input ports for electrical devices, universal power adaptors may come with large numbers of disparate power tips. This requires power adaptor manufacturers to design and manufacture the large number of disparate power tips, which can make the manufacturing process less efficient. Additionally, consumers may purchase power tips they do not need, which can lead to waste and extra expense for the consumer. These problems may be alleviated by designing power tips that are able to interface with multiple variably sized input ports.
Power tips are designed to be held in place by a frictional force between the power tip and the input port. The frictional force arises from contact between surfaces of the device interface and surfaces of the input port. The frictional force depends on the materials of the power tip and input port and the normal force between the power tip and input port. The normal force depends on the size and shape of the power tip and input port. As the elements of the power tip and input port contact and attempt to occupy the same space, those elements will be deformed and will exert a force resisting deformation, a component of which will be the normal force. The size and shape of the power tip control the extent that the input port and power tip attempt to occupy the same space and accordingly the deformation resisting force.
The frictional force results in the power tips having an insertion resistance and a pull resistance. A user will need to apply an insertion force sufficient to overcome the insertion resistance to insert the power tip into the input port of the electrical device. If the insertion resistance is too high, it will be difficult for users to insert the power tip into the electronic device. A user will need to apply a pull-out force sufficient to overcome the pull resistance to remove the power tip from the electronic device. If the pull resistance is too low, the power tip may dislodge from the input port when a user does not desire it to do so. Accordingly, improper insertion and pull resistances can have a large, negative impact on the experience of a user.
The insertion resistance and pull resistance for a power tip can be modified by changing sizes and shapes of the elements of the power tip during design to reduce the normal and frictional forces. Because the insertion resistance is often correlated to the pull resistance, power tips may be designed to appropriately balance the insertion resistance and the pull resistance. An acceptable insertion resistance may be no more than a threshold, such as 2, 3, 4, 5, 6, 7, 8, 9, or 10 lbs. Above this threshold, the power tip may be unusable due to an inability to insert the power tip and/or create strong negative reactions from some users. An acceptable pull resistance may be no less than a threshold, such as 0.5, 1, 1.5, 2, 2.5, 3, 3.5, or 4 lbs. Below this threshold, the power tip may become dislodged frequently enough to annoy users or substantially interfere with powering the electronic device. Instead of using thresholds, the power tip may be designed to come as close as possible to a target insertion resistance and/or a target pull resistance.
A first consolidated power tip 100a may comprise a device interface 110a comprising a cylinder. A first electrical contact 140a may be disposed on an inner surface of the cylinder, and a second electrical contact 150a may be disposed on an outer surface of the cylinder. The first electrical contact 140a may be electrically conductive material on the inner surface of the cylinder, or as illustrated, one or more arched strips of conductive material may run longitudinally along the inner surface of the cylinder. Similarly, the second electrical contact 150a may be conductive material on the outer surface of the cylinder, or some or all of the cylinder may be made from an electrically conductive material. The cylinder may further comprise an insulating section 170a that prevents direct electrical coupling of the electrical contacts 140a, 150a, which might create a short circuit. The cylinder may also comprise differently sized sections. In the illustrated embodiment, a first cylindrical section 112a is disposed proximally to the housing 120a and a second cylindrical section 114a is disposed distally from the housing 120a. An outer circumference of the first cylindrical section 112a is larger than an outer circumference of the second cylindrical section 114a, but inner circumferences of each cylindrical section 112a, 114a are equal. Depending on the input ports the consolidated tip is designed to fit, the cylinder may comprise additional section, the inner circumferences may vary between sections, or outer circumferences may be sized differently.
The consolidated power tip 100a is designed to ensure electrical coupling with each desired input port 210, 220, 230 while maintaining acceptable insertion and pull resistances. Design variables include: the outer and inner circumferences of the cylinder; the number of arched strips, the length of the arched strips, the height of the arched strips from the cylinder, and the rigidity of the arched strips; and other variations of the size and shape of the device interface 110a. The size and shape may be selected by choosing target insertion and/or pull-out resistances and minimizing the deviation of resistances for input ports 210, 220, 230 of interest from the target resistance values. Minimizing deviation may comprise minimizing the maximum deviation of any resistance from the target resistance values; minimizing the average deviation of all resistances from the target resistance values; or the like. Alternatively, the size and shape may be selected to ensure that the insertion resistance for each input port is below a predetermined threshold and the pull resistance for each input port is above a predetermined threshold. Different aspects of the size and shape may be altered to ensure that the interaction with each input port is within the predetermined thresholds.
In the illustrated embodiment, the outer circumference of the device interface 110a is large enough to frictionally engage with the outer walls of the cylindrical void of input port 210. This provides a pull resistance for input port 210 above a desired threshold, while contributing little to the insertion resistance of input ports 220 and 230. The arched strips and inner circumference are selected to balance the pull resistance of input port 220 with the insertion resistance of input port 230. The inner circumference is large enough to interface with the largest pin 232 without the insertion resistance exceeding the desired threshold. Yet, it still provides an adequate pull resistance for the input port 230. Additionally, the arched strips are deformable, so the largest pin 232 still fits in the device interface 110a even though it is wider than the space between the arched strips. For input port 220, the arched strips are sufficiently arched and rigid to engage frictionally with the pin 222 and provide pull resistance above the desired threshold. The large electrical contact 224 of the input port 220 can also contribute to the pull resistance. The device interface 110a is thus able to maintain acceptable insertion and pull resistances across a plurality of input ports 210, 220, 230.
A second consolidated power tip 100b may also comprise a device interface 110b comprising a cylinder. A first electrical contact 140b may again be disposed on an inner surface of the cylinder, and a electrical contact 150b may again be disposed on the outer surface of the cylinder. Additionally, the device interface 110b of the consolidated power tip 100b may comprise a center pin 160b to communicate power supply identification (“PSID”) information between the electronic device and the power adaptor. In other embodiments, the center pin 160b may act as the first electrical contact 140b, or a user may be able to select whether the center pin 160b or the inner surface of the cylinder acts as the first electrical contact 140b. The power tip 100b may comprise a memory containing the PSID information. Alternatively, the memory may be in the power adaptor and the adaptor interface may electrically couple the center pin 160b with the memory.
As shown in the cross-section views in
In the illustrated embodiment, the device interface 110b does not comprise arched strips. The insertion and pull resistance are instead controlled by varying the outer and inner circumference of the device interface 110b. Additionally, the circumference of the pin 160b may also be varied to alter the insertion or pull resistances of the various input ports 240, 250. In some embodiments, the desired input ports 240, 250 are sized and shaped such that the outer circumference can be sized to create pull resistance above the required threshold for one input port while the inner circumference can be sized to create pull resistance above the required threshold for the another input port. The pin 160b might then be sized to create a threshold pull resistance with another input port.
In other cases, the outer cylindrical void of one input port may have both a larger outer circumference and smaller inner circumference than the other input port. This may prevent one input port from having a pull resistance above the necessary threshold without the other input port having an insertion resistance exceeding the allowable threshold. In these cases, the pin 160b may be sized large enough to create the desired pull resistance with the one input port while the outer and inner circumference are sized to create a greater than threshold pull resistance with the other input port. In some embodiments, arched strips may be added to the pin 160b to adjust the insertion and pull resistances as well.
A third consolidated power tip 100c may comprise device interface 110c comprising a pin 160c with a first electrical contact 140c disposed on its surface. The device interface 110c may further comprise a cylinder with the second electrical contact 150c disposed on the outer surface of the cylinder but not the inner surface. An insulating section 170c may then insulate the electrical contact s 140c, 150c from direct electrical coupling. As shown in the cross-section view in
Consolidated Power Tips with Deformable Members
Consolidated Power Tips with Selectable Output Mode
If a programmable power adaptor automatically determines electrical requirements based on the power tip connected to it, it may not be able to determine electrical requirements from a consolidated tip. Alternatively, a power tip may be designed to regulate the electrical power provided such that it complies with electrical requirements of disparate electronic devices. Some consolidated power tips with a center pin may be designed to couple with input ports that use the center pin for different purposes, such as to act as a first electrical contact or to communicate PSID information. In any of these situations, a user may need to select different modes for the power tip based on the electrical requirements of different input ports. The consolidated power tip may comprise a mode selector to choose the appropriate output mode or the input port of interest.
It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the disclosure. The scope of the present disclosure should, therefore, be determined only by the following claims.
