PATENT DOCUMENT

Publication Number: US-9486956-B2
Application Number: US-201414267371-A
Country: US
Kind Code: B2

Title: Power adapter components, housing and methods of assembly

Abstract:
A dual-purpose transformer may be oriented in a plane perpendicular to planes in which printed circuit boards connected thereto are oriented, thereby providing structural support for a framework that can include a dense arrangement of internal power adapter components, in addition to stepping down voltage. Methods for ultrasonic welding are also provided and may be used to concurrently assemble, join and press-fit power adapter housing components. A ground lug is also provided that is shaped and located within a cover piece of a power adapter housing to allow for blind mating with a printed circuit board during an assembly process.

Claims:
What is claimed is: 
     
       1. A power adapter comprising:
 first and second printed circuit boards oriented in first and second planes, respectively, the first plane substantially parallel to the second plane; 
 a transformer extending between the first and second printed circuit boards, the transformer comprising:
 a first coiled winding defining a first opening, 
 a second coiled winding defining a second opening aligned with the first opening, and 
 a core comprising a first portion extending through the first and second openings and a second portion extending between the first and second coiled windings and the first printed circuit board; and 
 
 a body enclosing the first and second printed circuit boards. 
 
     
     
       2. The power adapter set forth in  claim 1  wherein the first and second coiled windings are embedded in the first and second printed circuit boards, thereby forming a board-to-board connection between the first and second printed circuit boards. 
     
     
       3. The power adapter set forth in  claim 1  wherein the core is a ferrite core that wraps around both the first and second coiled windings, the ferrite core protruding through and soldered to the first printed circuit board, and wherein a portion of the ferrite core is covered by an insulation element that is soldered to the second printed circuit board. 
     
     
       4. The power adapter set forth in  claim 1 , wherein the core intersects the longitudinal axes of both the first and second coiled windings. 
     
     
       5. The power adapter set forth in  claim 1  wherein the power adapter further includes first and second pin connectors, wherein the first coiled winding and the first printed circuit board are operatively coupled via the first pin connector, and wherein the second coiled winding and the second printed circuit board are operatively coupled via the second pin connector. 
     
     
       6. The power adapter set forth in  claim 1  wherein the first and second coiled windings are made from fiberglass and copper. 
     
     
       7. The power adapter set forth in  claim 1  further comprising a first connector that couples the first coiled winding to one of the printed circuit boards and a second connector that coupled the second coiled winding to the other of the printed circuit boards. 
     
     
       8. The power adapter set forth in  claim 7  wherein each of the first and second connectors are SMT connectors. 
     
     
       9. The power adapter set forth in  claim 1  wherein the first coiled winding is adhered to the second coiled winding with an adhesive. 
     
     
       10. The power adapter set forth in  claim 1  wherein the body has an L-shape that defines a plug region configured to receive a detachable plug. 
     
     
       11. The power adapter set forth in  claim 10  wherein the plug region includes first and second intersecting surfaces and the power adapter further comprises a connection opening positioned along the first surface and a ground plug positioned along the second surface. 
     
     
       12. The power adapter set forth in  claim 11  wherein a ground lug is electrically coupled between the ground plug and at least one of the first and second circuit boards. 
     
     
       13. The power adapter set forth in  claim 12  wherein the ground lug is connected to the at least one circuit board by a flexible connection member. 
     
     
       14. A power adapter comprising:
 first and second printed circuit boards oriented in first and second planes, respectively, the first plane substantially parallel to the second plane; 
 a transformer including: (i) first and second coiled windings extending between the first and second printed circuit boards thereby forming a board-to-board connection between the first and second printed circuit boards, and (ii) a ferrite core comprising:
 a first portion extending through a first opening defined by the first coiled winding and a second opening defined by the second coiled winding, and 
 a second portion extending between the first and second coiled windings and the first printed circuit board, wherein the ferrite core is electrically coupled to the first printed circuit board; 
 
 a first pin connector operatively coupled between the first coiled winding and the first printed circuit board; 
 a second pin connector operatively coupled between the second coiled winding and the second printed circuit board; and 
 a body configured to enclose the first and second printed circuit boards and the transformer. 
 
     
     
       15. The power adapter set forth in  claim 14  wherein the first coiled winding is adhered to the second coiled winding with an adhesive. 
     
     
       16. The power adapter set forth in  claim 14  wherein the body has an L-shape that defines a plug region configured to receive a detachable plug. 
     
     
       17. The power adapter set forth in  claim 16  wherein the plug region includes first and second intersecting surfaces and the power adapter further comprises a connection opening positioned along the first surface and a ground plug positioned along the second surface. 
     
     
       18. The power adapter set forth in  claim 17  wherein a ground lug is electrically coupled between the ground plug and at least one of the first and second circuit boards. 
     
     
       19. The power adapter set forth in  claim 18  wherein the ground lug is connected to the at least one circuit board by a flexible connection member.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application claims the benefit of prior filed U.S. Provisional Application No. 61/884,970, filed on Sep. 30, 2013, which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to power adapters and methods for assembling the same. More particularly, the present invention relates to improved transformer assemblies, grounding components and assembling techniques for power adapters. 
     Power adapter chargers are used to charge a wide range of electronic devices. For example, devices, such as tablets, laptops, netbooks, desktops, and all-in-one computers; cell, smart, and media phones; storage devices, portable media players, navigation systems, monitors, and others can be charged using power adapter chargers. In response to the increase in the number electronic devices sold and the decreasing size of those devices, demand has increased for highly efficient assembling techniques for power adapters and increased component density within power adapters. 
     However, many power adapter manufacturers continue to utilize assembly techniques that rely heavily on manual assembly and power adapter components that have gone unimproved or insufficiently improved for an extended period of time. For example, transformer assemblies continue to be a limiting factor in component density and current grounding components still require manual assembly. In addition, interference fits that require substantial manual labor and result in less robust power adapters continue to be employed by many manufacturers of power adapters. 
     BRIEF SUMMARY OF THE INVENTION 
     This invention provides improved power adapter components, including a redesigned transformer, a new grounding component and power adapter assembly techniques that utilize ultrasonic welding. For example, a dual-purpose transformer may be oriented in a plane substantially perpendicular to planes in which printed circuit boards connected thereto are oriented, thereby providing structural support for a framework that includes a dense arrangement of internal power adapter components, in addition to stepping down voltage. As another example, methods for ultrasonic welding are also provided and may be used to concurrently assemble, join and press-fit power adapter housing components. Furthermore, a ground lug is provided that is shaped and located within a power adapter to allow for blind mating with a printed circuit board during an assembly process that uses ultrasonic welding or other techniques. 
     According to one embodiment, a power adapter is provided. The power adapter can include first and second printed circuit boards oriented in first and second planes, respectfully. The first plane can be substantially parallel to the second plane. The plug connector can also include a transformer having first and second coiled windings extending between the first and second printed circuit boards. The first and second coiled windings can be oriented in a third plane substantially perpendicular to the first and second planes. The plug connector can also include a body configured to enclose the first and second printed circuit boards and the transformer. The body can include first and second faces oriented in planes substantially parallel to the first and second planes 
     According to another embodiment, a power adapter is provided. The power adapter can include electrical components configured to convert AC power received by the power adapter into external DC power, a housing configured to enclose the electrical components, a cover piece forming a plug region and a connection opening. The plug region and the connection opening can be configured to receive a corresponding detachable plug. The cover piece can include a ground prong for slidably engaging a notch formed in the detachable plug and a ground lug insert molded with the cover piece and operatively coupled to the ground prong. The ground lug can be electrically connected to a printed circuit board of the electrical components via a flexible member. The power adapter can also include contact pins positioned within the connector opening and operatively coupled to the electrical components. 
     According to yet another embodiment, the invention pertains to a method for assembling a power adapter. The method includes using a press to an L-shaped cover piece partially within a receiving area of the power adapter housing such that a first portion of the cover is deflected as a protrusion of the first portion contacts the receiving area and translates a deflecting force about an elbow of the cover piece; applying a horn to a second portion of the cover piece. The second portion can be oriented in a first plane perpendicular to a second plane in which the first portion is oriented when not deflected. The method can further include using a horn to provide ultrasonic acoustic vibration to the cover piece that causes the cover piece to be further seated within the receiving area as surfaces of the cover piece are ultrasonically welded to the receiving area, thereby positioning the protrusion within a receiving cavity of the receiving area such that the protrusion no longer translates the deflecting force. 
     Although aspects of the invention are described in relation to power adapters, it is appreciated that these aspects and methods can be used in a variety of different environments such as tablets, laptops, netbooks, desktops, and all-in-one computers; cell, smart, and media phones; storage devices, portable media players, navigation systems, monitors, and others. 
     To better understand the nature and advantages of the present invention, reference should be made to the following description and the accompanying figures. It is to be understood, however, that each of the figures is provided for the purpose of illustration only and is not intended as a definition of the limits of the scope of the present invention. Also, as a general rule, and unless it is evident to the contrary from the description, where elements in different figures use identical reference numbers, the elements are generally either identical or at least similar in function or purpose. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  illustrates a perspective view of a transformer connected with first and second printed circuit boards, according to an embodiment of the present invention; 
         FIGS. 1B-1F  are perspective views of the transformer of  FIG. 1A  in various stages of assembly, illustrating its various components, according to an embodiment of the present invention; 
         FIG. 2  illustrates a method for assembling and concurrently ultrasonically welding together components of a power adapter body, according to an embodiment of the present invention; 
         FIGS. 3A-3C  are side views of a cover piece and a power adapter housing at different steps of the assembly method of  FIG. 2 , according to an embodiment of the present invention; 
         FIGS. 3A-1 and 3B-1  are cross-sectional front views corresponding to the side views shown in  FIGS. 3B and 3C , respectively, according to an embodiment of the present invention; 
         FIG. 3D  illustrates a simplified perspective view of the power adapter housing of  FIGS. 3A-3C  at the conclusion of the method of  FIG. 2 , but with the cover piece removed for illustrative purposes, according to an embodiment of the present invention; 
         FIGS. 4A and 4B  are side views of a cover piece and a power adapter housing at different steps of an ultrasonic welding method, according to an embodiment of the present invention; 
         FIG. 4C  illustrates a simplified perspective view of solid state welds formed on the power adapter housing of  FIGS. 4A and 4B , but with the cover piece removed for illustrative purposes, according to an embodiment of the present invention; 
         FIGS. 5A and 5B  are exploded and simplified perspective views, respectively, of a cover piece for a power adapter housing that includes a grounding lug, according to an embodiment of the present invention; 
         FIG. 5C  is a simplified perspective view of the cover piece of  FIGS. 5A-5B  assembled with a power adapter housing, according to an embodiment of the present invention; and 
         FIGS. 6A and 6B  are simplified perspective and front views of a power adapter housing that is integrally formed with a receptacle connector. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention will now be described in detail with reference to certain embodiments thereof as illustrated in the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without some or all of these specific details. In other instances, well known details have not been described in detail in order not to unnecessarily obscure the present invention. 
     Embodiments of the present invention are directed to dual-purpose transformers that may be oriented in a plane perpendicular to planes in which printed circuit boards connected thereto are oriented. These transformers may provide traditional transformer functionality, e.g., stepping down voltage for use by devices. In addition, these transformers may provide structural support for printed circuit boards such that these transformers and printed circuit boards can serve as the framework for a multiplicity of components internal to a device, e.g., a power adapter. This dual-purpose—voltage regulating and structurally supporting—transformer may allow for greater component density as one component may replace the need for and function of two components. 
     Embodiments of the present invention are also directed to an ultrasonic welding process that may be used to assemble power adapter components. For example, an ultrasonic welding machine may bring components, e.g., power adapter housing parts, together but slightly offset from their fully assembled positions. The ultrasonic vibrations may cause the interfacing portions of the components to deform such that they are able to travel to their fully assembly position, whereas the un-deformed components would not have been able to connect in their fully assembly positions because they were sized to overlap instead of interconnect. Thus, this assembly process may modify the shape of components, albeit slightly, such that they may be assembled while welding them together. Other portions of these components may be concurrently and similarly welded together or otherwise joined, e.g., via an interference fit or simply being positioned flush against each other, as a result of the travel that occurs during the ultrasonic welding process. 
     Embodiments of the present invention are also directed to a ground lug. The ground lug may be coupled between a ground line of a printed circuit board and a ground plug of the power adapter. The ground lug may be shaped and located within a power adapter such that it may be blindly mated with a printed circuit board when the power adapter is fully assembly. In this manner, no placing and soldering of wires may be required to establish the coupling between the ground plug and a ground line. A flexible member, a leaf spring contact, may provide electrical coupling and positioning tolerance by flexing as necessary to adapt to and to connect with the ground lug in its final assembled position. For example, the flexible member may be biased to extend from the printed circuit board farther than necessary towards the assembled position of the ground lug. Accordingly, the ground lug may still connect with the flexible member even if it is slightly out of position, e.g., positioned farther away from the flexible member than originally expected, and the flexible member may deflect and adjust to the position of the ground lug while maintaining electrical contact therewith. 
     These embodiments are further discussed in the following subsections of the Detailed Description: (I) dual-purpose transformers for power adapters, and (II) ultrasonic welding processes for assembling power adapter housings, and (III) ground lugs for power adapters. 
     I. Dual-Purpose Transformers for Power Adapters 
     As mentioned above, transformers continue to be a limiting factor in component density. For example, transformers are typically oriented in planes parallel to the planes in which printed circuit boards are oriented when connected with the transformers and assembled in power adapter housings. This configuration does not create a framework for the inclusion of components in a high density manner. Rather, it is a plug-and-play style design that lacks consideration for what functions could be provided by the transformer, other than just varying and/or isolating voltage wherever implemented. In contrast, as described below, the dual-purpose transformers for power adapters of the present invention provide a structural functionality in addition to traditional functions. 
       FIG. 1A  illustrates a perspective view of transformer  100  connected with first and second printed circuit boards  106 ,  108 , according to an embodiment of the present invention. Transformer  100  includes first and second coiled winding  102 ,  104  extending between first and second printed circuit boards  106 ,  108 , bracing first and second printed circuit boards  106 ,  108  together as shown in  FIG. 1A . This bracing may be accomplished by embedding tips of the coiled windings within the printed circuit boards  106 ,  108 , which may also facilitate a board-to-board connection for first and second printed circuit boards  106 ,  108 . For example, tips  110   a ,  110   b  of first coiled winding  102  may protrude through first and second openings  112   a ,  112   b  of second printed circuit board  108 . Soldering may be used to connect tips  110   a  and  110   b  to second printed circuit board  108  at openings  112   a  and  112   b , respectively. Additional tips (e.g., tips  126   a ,  126   b , as shown in  FIG. 1B ) on first coiled winding  102  may also protrude through third and fourth openings (not shown, but see, e.g., openings  112   a ,  112   b ) of first printed circuit board  106 . These tips, like tips  110   a ,  110   b , may be soldered at the corresponding third and fourth openings of first printed circuit board  106 . Accordingly, first and second coiled winding  102 ,  104  may be oriented in a plane extending between first and second printed circuit boards  106 ,  108 , which plane may be perpendicular (or, e.g., within about 10 degrees of perpendicular) to planes in which the first and second printed circuit boards  106 ,  108  are oriented. 
     Transformer  100  may also include an insulation element  114  protruding through a first notch  116  in second printed circuit board  108 . Similarly transformer  100  also includes and I-core  118  (as further discussed below) that protrudes through a second notch  120 . Pin headers such as surface mount technology (SMT) headers may further electrically couple the coiled windings to the printed circuit boards. For example, as shown in  FIG. 1A , SMT headers  122  and  124  (partially shown) further electrically couple coiled windings  102  and  104  to printed circuit boards  106  and  108 , respectively. Thus, transformer  100  may be electrically and mechanically connected with first and second printed circuit boards  106 ,  108  to form a structural framework for the inclusion of additional electrical components. As structural members of this framework, first and second coiled winding  102 ,  104  may be sized and constructed to support loads exerted on first and second printed circuit boards  106 ,  108 . For example, first and second coiled windings  102 ,  104  may have a thickness, extending in a direction parallel to the planes in which the first and second printed circuit boards are oriented, of 2 mm or between about 1.5 mm and 2.5 mm. First and second coiled winding  102 ,  104  may be made from fiberglass and copper. 
     This framework, wherein first and second coiled windings  102 ,  104  brace first and second printed circuit boards  106 ,  108  together as shown in  FIG. 1A , may be utilized within a number of the devices listed above, and, in particular, within a power adapter body or housing (e.g., body or housing  600 , as shown in  FIG. 6A ). For example, first and second printed circuit boards  106 ,  108  may be positioned within a power adapter housing such that they are adjacent to and oriented parallel (or, e.g., within about 10 degrees of parallel) to side faces of a power adapter housing, resulting in first and second coiled windings  102 ,  104  being positioned such that they are oriented in a plane perpendicular (or, e.g., within about 20 degrees of perpendicular) to planes in which the side faces of the power adapter housing are oriented. 
     Although first and second printed circuit boards  106 ,  108  are shown in  FIG. 1A  as having a specific shape and size, these boards may also be sized differently to adapt to the housing in which they are included. For example, although shown as being flat in  FIG. 1A , printed circuit boards  106 ,  108  may have curvatures, surfaces extending in a straight direction from a substantially flat portion of the printed circuit board and/or other openings and notches. Furthermore, first and second printed circuit boards  106 ,  108  may each be uniquely sized and shaped, instead of having the same size and shape as shown in  FIG. 1A . These variations of first and second printed circuit boards  106 ,  108  may still connect with transformer  100  as shown in  FIG. 1A . Alternatively, pin connectors may be used for this connection. For example, pin connectors (e.g., one per coiled winding) may be used to connect first and second coiled windings  102  and  104  with first and second printed circuit boards  106  and  108 , respectively. 
     In addition to serving as a structural support member of the above described framework, transformer  100  may also perform traditional transformer function. For example, transformer  100  may be configured to convert the AC power provided to a device, e.g., a power adapter, by the power source into power usable by the devices or, in the case of a power adapter, external power that is transferable to other devices connected to an electrical connection extending from the power adapter. More specifically, transformer  100  may convert electrical power from one voltage-current level to another voltage current level. The external power may be widely varied. For instance, transformer  100  may be adapted with different voltage ratings. In one implementation, the voltage of the external power ranges from about 8 volts to about 20 volts. Thus, one of first and second printed circuit boards  106 ,  108  may be the higher-voltage printed circuit board and the other may be the lower-voltage circuit board. 
       FIGS. 1B-1F  are perspective views of the transformer of  FIG. 1A  in various stages of assembly, illustrating its various components, according to an embodiment of the present invention.  FIG. 1B  shows first coiled winding  102  separated from second coiled winding  104  and including tips  112   a ,  112   b  and SMT header  124 .  FIG. 1B  also shows previously referenced additional tips  126   a ,  126 , which tips may protrude through third and fourth openings (not shown, but see, e.g., openings  112   a ,  112   b ) of first printed circuit board  106  (shown in  FIG. 1A ). FIG.  1 B also illustrates an adhering region  128  of coiled winding  102 , which region may interface with second coiled winding  104  (shown in  FIG. 1A ) when first and second coiled windings  102 ,  104  are adhered together, as discussed further below. First coiled winding  102  may also include a number of openings for interconnecting with other components of transformer  100 . For example, first coiled winding  102  includes openings  130   a ,  130   b  for receiving dowel pins that extend through corresponding openings of second coiled winding  104  (see openings  136   a ,  136   b , as shown in  FIG. 1C ). Headers openings  132   a ,  132   b  may also be included and configured to receive pins of SMT header  122  (e.g., see pins  140   a ,  140   b , as shown in  FIG. 1C ). Yet another opening, an opening  134 , may also be included. Opening  134  may be configured to receive a portion of an E core (e.g., E core  144 , as shown in  FIG. 1D ) when assembled with second coiled winding  104 . 
       FIG. 1C  shows second coiled winding  104  assembled with first coiled winding  102 . As mentioned above, second coiled winding  104  may be adhered to first coiled winding  102 . A number of different adhesives could be used to accomplish this, including epoxy and silicon adhesives. In addition, dowel rods may be used to secure first and second coiled windings  102  together. For example, second coiled winding  104  may include opening  136   a ,  136   b , corresponding to openings  130   a  and  130   b , for receiving dowel pins. Dowel pins  138   a ,  138   b  may be inserted through openings  136   a  and  130   a  and openings  138   b  and  138   b , respectively, thereby providing additional mechanical support for securing together first and second coiled windings  102 ,  104 . Although not their primary function, SMT headers  122 ,  124  may similarly provide mechanical support. For example, pins  140   a ,  140   b  of SMT headers  122  may be inserted into header openings  132   a ,  132   b  (shown in  FIG. 1B ). Second coiled winding  104  may also include an opening  142  that is configured to receive a portion of an E core (e.g., E core  142 , as shown in  FIG. 1D ) when assembled with first and second coiled windings  102 ,  104 . 
     Just as first and second printed circuit boards  106 ,  108  are shown in  FIG. 1A  as having a specific shape and size, first and second coiled windings  102 ,  104  are also shown as having specific shape and size (see  FIG. 1C ). However, first and second coiled windings  102 ,  104  may also be sized differently to adapt to the housing, e.g., a power adapter housing, in which they are included. For example, in a larger housing or a housing including a larger number of internal components, it may be necessary to provide more space between the printed circuit boards (e.g., printed circuit boards  106 ,  108 ) to accommodate the internal components. Accordingly, first and second coiled windings  102 ,  104  may extend a greater distance in bridging the gap between the printed circuit boards, while still being oriented in a plane extending between the printed circuit boards, which plane is substantially perpendicular to the planes in which the printed circuit boards are oriented. 
     Referring to  FIGS. 1D-1F , a ferrite core may be assembled with first and second coiled windings  102 ,  104 . For example, as shown in  FIG. 1D , an E-core  144  may be assembled over first and second coiled windings  102 ,  104 , extending through opening  134  and opening  142  (shown in  FIGS. 1B-1C ). As previously mentioned, I-core  118  may be assembled over second coiled windings  104  and assembled with E-core  144 , as shown in  FIG. 1E . I-core  118  may also be epoxied to E-core  144  to hold the ferrite core together. Copper tape may be wrapped around I-core  144  about its longitudinal direction and an insulation element  114 , e.g., made from polyester resin or other non-conducive materials, may also be epoxied to first and second coiled windings  102 ,  104 , as shown in  FIG. 1F . As discussed previously and shown in  FIG. 1A , insulation element  114  may also protrude through first notch  116  in second printed circuit board  108   a  and I-core  118  may protrude through second notch  120 . 
     Although transformer  100  has been described above as including a number specific components, additional components and substitute components may also be implemented for transformer  100 . The variations may account for various environmental factors, including the types and sizes of devices in which transformer  100  is implemented. In addition, these variations may be adapted according to methods of assembly used for the device housings, e.g., a power adapter body or housing. For example, a power adapter body may be primarily integrally formed and include a small opening for receiving internal components. Examples of one such method of assembly for a power adapter body, which may be well suited for the inclusion of transformer  100 , are illustrated in the following figures. 
     II. Ultrasonic Welding Processes for Assembling Power Adapter Housings 
     As mentioned above, many traditional assembling techniques for device housings such as power adapter bodies or housings rely on interference fits that require substantial manual labor during the assembly process. The housings are also formed from a large number of discrete elements. These designs result in less robust power adapters that require longer and more labor intensive assembling processes, but these processes continue to be employed by many manufacturers of power adapters. 
     The method of assembly of the present invention may be employed for a number of different types of devices and corresponding device housing design styles. However, for simplicity, the present invention is described with reference to one particular device housing type and style; a power adapter housing that is integrally formed except for having an inlet cover that is assembled with the integrally formed housing using methods of the present invention. An example of these methods of assembling a power adapter is illustrated in the following figures. 
       FIG. 2  illustrates a method  200  for assembling and concurrently ultrasonically welding together components of a power adapter body, according to an embodiment of the present invention. Method  200  may be used to assemble an inlet cover or cover piece with a power adapter housing. Each step of method  200  is described below with reference to figures that physically illustrate the respective steps. 
     At a step  205 , an L-shaped cover piece may be seated or placed partially within a receiving area of a power adapter housing.  FIGS. 3A-3C  are side views of a cover piece and a power adapter housing at different steps of assembly method  200 , according to an embodiment of the present invention. And  FIGS. 3A-1 and 3B-1  are cross-sectional front views corresponding to the side views shown in  FIGS. 3B and 3C , respectively, according to an embodiment of the present invention. As shown in  FIG. 3A , which may correspond to step  205 , a press  300  or other positioning machine has placed an L-shaped cover piece  302  (e.g., cover piece  500 , as shown in  FIG. 5A ) partially within a receiving area  304  of a power adapter housing  306 . The press may hold cover piece  302  and power adapter housing  306  under pressure such that they remain appropriately positioned throughout an ultrasonic welding process. Due to the shape of cover piece  302  and receiving area  304 , the positioning of cover piece  302  causes a first portion  302   a  of cover piece  302  to deflect as a protrusion  302   b  of cover piece  302  comes into contact with receiving area  304 , as shown in  FIG. 3A . This deflection occurs as a force—a deflection force—is exerted by receiving area  304  on protrusion  302   b , which force is translated by protrusion  302   b  about an elbow  302   c  of cover piece  302 , causing first portion  302   a  to deflect, as shown in  FIG. 3A . 
     After cover piece  302  and power adapter housing  306  are securely positioned as shown in  FIG. 3A , method  200  may proceed to the next step. An example of the next step is shown in the following figures. 
     At a step  210 , an anvil or horn is applied to a second portion of the cover piece. For example, as shown in  FIG. 3B , a horn  308  is applied in an application direction  310  to second portion  302   d . As mentioned earlier, this second portion  302   d  may be oriented in a place perpendicular to a plane in which first portion  302   b  is oriented when not deflected (e.g., see first portion  302   b  in  FIG. 3C  and cover piece  500  in  FIG. 5A ). Horn  308  may be an ultrasonic welding transducer that is used to apply ultrasonic acoustic vibrations to one or more workpieces, e.g., cover piece  302  and/or power adapter housing  306 , during ultrasonic welding operations. Horn  308  may be shaped to conform to second portion  302   d  and to accommodate a ground plug  312  that may extend from second portion  302   d . Following step  210 , cover piece  302  may be positioned within receiving area  304 . Accordingly, as shown in  FIG. 3A-1 , edges  314   a  and  314   b  of second portion  320   d  may be positioned adjacent to ledges  316   a  and  316   b  of receiving area  304 , respectively. 
     After horn  308  is applied to second portion  302   d , method  200  may proceed to the next step. An example of the next step is shown in the following figures. 
     At step  215 , horn  308  may provide ultrasonic acoustic vibration (e.g., about application direction  310 ) to second portion  302   d  of cover piece  302  that causes cover piece  302  to be further seated within receiving area  304  as surfaces (e.g., edges  314   a ,  314   b ) of cover piece  302  are ultrasonically welded to receiving area  304  (e.g., at ledges  316   b ,  316   a ), as shown in  FIG. 3C .  FIG. 3  also illustrates that following the providing of ultrasonic acoustic vibration, edges  314   a  and  314   b  are pushed past the original positions of now deformed ledges  316   a ,  316   b , thereby creating solid state welds  318   a ,  318   b , as shown in  FIG. 3B-1 . In addition, first portion  302   a  has also traveled such that protrusion  302   b  is positioned within a receiving cavity  320  of receiving area  304  and no longer translates the deflecting force that previously caused first portion  302   a  to deflect. Accordingly, this ultrasonic welding step also press-fits first portion  302   a  within receiving area  304  and fully assembles cover piece  302  with power adapter housing  306 . 
       FIG. 3D  illustrates a simplified perspective view of the power adapter housing of  FIGS. 3A-3C  at the conclusion of method  200 , but with cover piece  302  removed for illustrative purposes, according to an embodiment of the present invention.  FIG. 3D  shows solid state welds  318   a ,  318   b  as well as an additional weld  318   c  extending between solid state welds  318   a  and  318   b . Weld  318   c  may have occurred between another edge (not shown) of second portion  302   d  and another ledge (not shown) of receiving area  304  during step  215 . 
     The frequency of the ultrasonic acoustic vibration applied during step  215  may vary based on the materials of cover piece  302  and power adapter housing  306 . For example, where cover piece  302  and power adapter housing  306  are made from polycarbonate, an appropriate frequency for the ultrasonic acoustic vibration provided during step  215  may be 20,000 hertz (Hz) or another frequency between about 18,000 Hz and about 22,000 Hz. Cover piece  302  and power adapter housing  306  may also be made from other polymers, e.g., acrylonitrile butadiene styrene (ABS), and the provided ultrasonic acoustic vibration may be tuned accordingly. 
     In addition to the welds mentioned above, other welds may also occur during step  215 . For example, the ultrasonic acoustic vibration provided at step  215  may also be experienced at the interface between protrusion  302   b  and surfaces of receiving area  304 , resulting in a solid state weld occurring between protrusion  302   b  and surfaces of receiving area  304 . Although method  200  was described above with reference to a particular device housing, method  200  may be used for a variety of other device housings, including other power adapters and mobile media devices. For example, parts that are typically assembled with a device housing using press-fitting may instead be assembled with device housings using a combination of ultrasonic welding and press-fitting; the travel experienced by a part during ultrasonic welding may press-fit other portions of the part (e.g., protrusion  302   b ) to the housing. 
     In other embodiments, an assembling method may include applying a horn to multiple portions of a part to concurrently cause multiple welds to be formed between a part and a housing with which it is being assembled; examples of this are illustrated in the following figures. 
       FIGS. 4A and 4B  are side views of a cover piece and a power adapter housing at different steps of an ultrasonic welding method, according to an embodiment of the present invention. At a first step, an L-shaped cover piece may be seated or placed partially within a receiving area of a power adapter housing and a horn may be applied to first and second portions of the cover piece. 
     As shown in  FIG. 4A , which may correspond to the first step, a press or other positioning machine may have already placed an L-shaped cover piece  400  (e.g., cover piece  500 , as shown in  FIG. 5A ) partially within a receiving area  402  of a power adapter housing  402 . The press may hold cover piece  400  and power adapter housing  406  under pressure such that they remain appropriately positioned throughout an ultrasonic welding process. A horn  406  can be applied in application directions  408   a ,  408   b  to multiple surfaces of cover piece  400 . Horn  406  may be an ultrasonic welding transducer that is used to apply ultrasonic acoustic vibrations to one or more workpieces, e.g., cover piece  400  and/or power adapter housing  404 , during ultrasonic welding operations. As shown in  FIG. 4A , horn  406  may be shaped to conform to concurrently interface with multiple surfaces of cover piece  400  and to accommodate a ground plug  410  that may extend from cover piece  400 . Following this first step, cover piece  400  may be positioned within receiving area  402  such that surfaces of cover piece  400  and receiving area  402  are adjacent to each other. 
     At the next or second step, horn  406  may provide ultrasonic acoustic vibration about application directions  408   a ,  408   b  to cover piece  400 . As shown in  FIG. 4B , which corresponds to the conclusion of the second step, cover piece  400  is further seated within receiving area  402  and surfaces of cover piece  400  have been ultrasonically welded to surfaces of receiving area  402 .  FIG. 4C  illustrates a simplified perspective view of solid state welds formed on the power adapter housing of  FIGS. 4A and 4B  (housing  404 ), but with cover piece  400  removed for illustrative purposes, according to an embodiment of the present invention. The solid state welds formed by the second step may include welds  412   a ,  412   b  and welds  414   a ,  414   b . Welds  412   a ,  412   b  may have been formed by the ultrasonic acoustic vibrations applied in direction  408   a , while welds  414   a ,  414   b  may have been formed by the ultrasonic acoustic vibrations applied in direction  408   b.    
     The frequency of the ultrasonic acoustic vibration applied during the second step may vary based on the materials of cover piece  400  and power adapter housing  404 . For example, where cover piece  400  and power adapter housing  404  are made from polycarbonate, an appropriate frequency for the ultrasonic acoustic vibration provided during the second step may be 20,000 hertz (Hz) or another frequency between about 18,000 Hz and about 22,000 Hz. Cover piece  400  and power adapter housing  404  may also be made from other polymers, e.g., ABS, and the provided ultrasonic acoustic vibration may be tuned accordingly. 
     Although, the steps of  FIGS. 4A-4C  were described above with reference to a particular device housing, these steps may be used for a variety of other device housing, including other power adapters and mobile media devices. For example, parts that are typically assembled with a device housing using press-fitting may instead be assembled with device housings using these steps. 
     In addition to the advantages provided by methods of assembly described above, power adapter housings may also include features to make corresponding methods of assembly even more simple and efficient. Examples of these features for power adapters, which power adapters may be assembled according to the methods described above and/or include embodiments of the transformer described above, are illustrated in the following figures. 
     III. Ground Lugs for Power Adapters 
     As mentioned previously, many of the current assembling techniques for power adapter housings and other device housings require a significant amount of manual assembly time. For example, traditional grounding components are often interconnected manually using wiring. Embodiments of the present invention are directed to a ground component for a power adapter that can be interconnected with other grounding components using blind mating, instead of manually added wires. 
       FIGS. 5A and 5B  are exploded and simplified perspective views, respectively, of a cover piece for a power adapter housing that includes a grounding lug, according to an embodiment of the present invention. Cover piece  500  may include a ground plug  502  partially inserted into an opening  504  to connect with an inserted molded ground lug  506 . Ground plug  502  may be secured to cover piece  500  using a screw  508  that is threadingly coupled to ground plug  502  via a threaded opening (not shown) in ground plug  502 . The exposed end of screw  508  may be insulated using a screw end cap  510  that is made from a non-conductive material, e.g., polycarbonate or ABS. As shown in  FIG. 5B , a mating end  506   a  of ground lug  506  may extend from a back surface  512  of cover piece  500 . Ground lug  506  may be used to connect electrical components to ground plug  502  for grounding. As such, ground lug  506  may be made from electrically conductive material. For example, ground lug  506  may be made from brass and plated with nickel. Cover piece  500  may be assembled with a power adapter housing, as shown in the following figure. 
       FIG. 5C  is a simplified perspective view of the cover piece of  FIGS. 5A-5B  assembled with a power adapter housing, according to an embodiment of the present invention. Cover piece  500  may be assembled with a power adapter housing  550  to form a power adapter  552 . Power adapter  552  may be configured to receive a detachable plug at cover piece  500 , which forms a plug region  514 , i.e., a region that interfaces with the detachable plug when connected therewith, and a connection opening  516 . The detachable plug may include electrical contact surfaces that engage electrical contact pins (not shown) positioned within connection opening  514 . Accordingly, when a corresponding detachable plug is received at cover piece  500 , prongs of the detachable plug may be electrically coupled to power adapter  552  such that electrical current may pass through the prongs of the detachable plug to the contact pins (not shown) in connection opening  514 . In order to securely hold the detachable plug at cover piece  500 , the detachable plug may include a notch for slidably engaging ground plug  502 , thereby holding the detachable plug in an attached position. 
     As shown in  FIG. 5C , when cover piece  500  is assembled with a power adapter housing  550 , a mating end  506   a  of ground lug  506  may extend such that it contacts a flexible member  554  of a printed circuit board  556  (e.g., printed circuit board  106 , as shown in  FIG. 1A ). Thus, blind mating may occur between ground lug  506  and printed circuit board  556 , wherein no manual effort may be required to ensure ground lug  505  contacts flexible member  554  after cover piece  500  is assembled with a power adapter housing  550 . This blind mating may allow ground plug  502  to couple to a ground line of printed circuit board  556  via ground lug  506 . 
     Flexible member  554  may be a leaf spring contact, another spring connection or even a pressure connection that provides electrical coupling and positioning tolerance by flexing as necessary to adapt to and to connect with ground lug  506  in its final assembled position. For example, flexible member  554  may be biased to extend farther than necessary from printed circuit board  556  and toward an expected assembled position of ground lug  506 . Accordingly, ground lug  506  may still connect with flexible member  554  even if it is slightly out of the expected assembled position, e.g., positioned farther away from flexible member  554  than it would have been in the expected assembled position, and flexible member  554  simply may deflect to adjust to the position of ground lug  506  while maintaining electrical contact therewith. 
     Although ground lug  506  is shown in  FIGS. 5A-5C  and described above as having a specific size, shape and location, the size, shape and location of ground lug  506  may be varied, e.g., where the ground plug&#39;s position is varied or when the ground lug is implemented with different power adapters or housings of other devices. In addition, ground lug  506  can include a flexible member for connecting with flexible member  554  and flexible member  554  may be replaced with a rigid member. Furthermore, ground lug  506  may not be insert molded with cover piece  500  and may simply rely on screw  508  or other components for connecting to ground plug  502 . 
     In addition to including components that use blind mating to reduce manual assembly time, embodiments of power adapter housings of the present invention may be integrally formed with components that are traditionally assembled with power adapter housings or housings of other electronic devices. Examples of components integrally formed with a power adapter are shown in the following figures. 
       FIGS. 6A and 6B  are simplified perspective and front views of a power adapter housing that is integrally formed with a receptacle connector. As shown in  FIG. 6A , a power adapter housing  600  (e.g., power adapter housing  550 ) may include an opening  602  that provides access to a Universal Series Bus (USB) port  604 . Housing  602  may be made from polycarbonate or other polymer such as ABS or even metal. Opening  602  may be integrally formed with the housing, and contacts (e.g., contacts  606   a - 606   d , as shown in  FIG. 6B ) and/or other elements of USB connector  604 , some of which are shown in  FIG. 6B , may be insert molded with housing  600 . As shown in  FIG. 6B , USB port  604  includes a plurality of contacts  606   a - 606   d . Some of the contacts are for transmitting data while others are for transmitting power. Concerning the contacts for transmitting power, these contacts may be coupled to a power source through various components (e.g., printed circuit board housed within power adapter housing  600 ) so as to provide power to a data transmission line when connected thereto. 
     Although port  604  is described above as being a USB port, port  604  may also be a FireWire (IEEE 1394) port. In addition, the contacts and other components of port  604  may alternatively be provided at port  604  via machining out gaps for them and them assembling them therewith, instead of being integrally formed with gaps and having components insert molded therewith. 
     The specific details of particular embodiments may be combined in any suitable manner or varied from those shown and described herein without departing from the spirit and scope of embodiments of the invention. Moreover, the invention may also provide features for electronic devices other than power adapters, such as other devices that include transformers, utilize interference fits, or use wires for grounding components. 
     The above description of exemplary embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.

Metadata:
Filing Date: 20140501
Publication Date: 20161108
Grant Date: 20161108
Priority Date: 20130930
Inventors: VILLARREAL CESAR LOZANO
KWAN ALEXANDER M.
OBERTHER KEVIN A.
Assignee: APPLE INC
CPC Classifications: [{"code": "Y10T29/49915", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C66/81419", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R43/0207", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/5045", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C65/565", "inventive": true, "first": true, "tree": "[]"}, {"code": "B29C66/9513", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C65/081", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/112", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R31/065", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29L2031/3481", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C66/114", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/8432", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/542", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C65/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/8322", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/244", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/71", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01F27/2804", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/306", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F2027/2819", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01F2027/2809", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/655", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/9512", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/655", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R43/0207", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C65/081", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C65/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R31/065", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C66/8322", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F2027/2809", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29K2055/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/5045", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F2027/2819", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C66/71", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C66/112", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F27/2804", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/8432", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T29/49915", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C65/565", "inventive": true, "first": true, "tree": "[]"}, {"code": "B29C66/542", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/81419", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/244", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/114", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/9512", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29K2069/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01F27/306", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/9513", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29L2031/3481", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 52740591