PATENT DOCUMENT

Publication Number: US-8021183-B2
Application Number: US-36345209-A
Country: US
Kind Code: B2

Title: Cold headed electric plug arm

Abstract:
This is directed to a power adapter plug arm manufactured from a single piece of material. The plug arm can include a plug operative to extend into a wall socket, an elongated plate coupled to an end of the plug such that the plug extends from a first surface of one end of the plate, and a pin coupled to the opposite end of the plate and extending from the opposite surface of the plate. The pin can be operative to engage a circuit board of the power adapter to provide power received from the wall socket to an electronic device coupled to the power adapter. To enhance the strength of the plug arm, the plate can be manufactured by creating a co-axial plug and a stem from a single piece of material, bending the stem, and cold heading the bent portion of the stem to form a plate. Because the cold heading process involves cold working the material, the arm and in particular the bridge member at the interface between the plate and the stem can become stronger as a result of the manufacturing process.

Claims:
1. An electrical plug arm, comprising:
 a plug insert portion having a shape suitable for insertion into a corresponding electrical receptacle, the plug insert portion comprising a plug and a stem, wherein the plug comprises a surface perpendicular to a central axis of the plug insert portion at an interface between the plug and the stem, and wherein the surface comprises a band between a periphery of the plug and a periphery of the stem around the entirety of the periphery of the stem; 
 a cold stamped portion having a substantially flat surface perpendicular to a central axis of the plug insert portion, wherein a thickness of the cold stamped portion along the central axis of the plug insert portion is smaller than dimensions of the cold stamped portion measured along the substantially flat surface; and 
 a bridge portion that connects the plug insert portion to one end of the cold stamped portion, wherein the plug insert, cold stamped, and bridge portions are formed from a single piece of material. 
 
     
     
       2. The electrical plug arm of  claim 1 , further comprising:
 a pin coupled to the cold stamped portion, the pin extending from a surface of the cold stamped portion opposite the surface of the cold stamped portion from which the plug insert portion extends. 
 
     
     
       3. The electrical plug arm of  claim 2 , wherein the distance between the pin and the bridge portion is at least one of substantially equal to or longer than the length of the plug insert portion. 
     
     
       4. The electrical plug arm of  claim 1 , wherein:
 the cold stamped portion comprises an elongated shape; and 
 the bridge portion is located at one end of the elongated shape. 
 
     
     
       5. The electrical plug arm of  claim 1 , wherein the cold stamped portion is longer than the plug insert portion. 
     
     
       6. The electrical plug arm of  claim 1 , wherein:
 the plug comprises a first cross-section substantially the same as the cross-section of the corresponding receptacle; and 
 the stem comprises a cross-section that fits within the first cross-section, the stem and plug being co-axial. 
 
     
     
       7. The electrical plug arm of  claim 6 , wherein the stem is operative to be encased within a protrusion, the protrusion having a cross-section substantially equal to the first cross-section. 
     
     
       8. The electrical plug arm of  claim 7 , wherein:
 the electrical plug arm is constructed from an electrically conductive material; and 
 the protrusion is constructed from an electrically isolating material. 
 
     
     
       9. An electrical plug arm incorporated in a plug, comprising:
 a plug insert portion having a shape suitable for insertion into a corresponding electrical receptacle; 
 a plate portion comprising a plate characterized by a substantially flat surface perpendicular to a central axis of the plug insert portion, wherein the plug insert portion and the plate portion are constructed from a single piece of material, and wherein the plug insert portion extends from a first end of the plate portion such that an interface between the plug insert portion and the plate portion is offset from a periphery of the plate portion; and 
 an electrical connection extending from the plate portion and for receiving a lead providing an electrical connection for the plug arm, wherein the electrical connection is not aligned with an axis of the plug insert portion. 
 
     
     
       10. The electrical plug arm of  claim 9 , wherein the plate portion further comprises:
 an aperture for receiving the electrical connection, wherein the electrical connection comprises a pin. 
 
     
     
       11. The electrical plug arm of  claim 10 , wherein:
 the pin is operative to engage the plate portion through the aperture, such that the pin extends substantially perpendicular from the plate portion. 
 
     
     
       12. The electrical plug arm of  claim 11 , wherein:
 the plate portion comprises a second surface opposite the substantially flat surface; 
 the plug insert portion extends from the substantially flat surface; and 
 the pin extends from the second surface. 
 
     
     
       13. The electrical plug arm of  claim 9 , further comprising:
 a bridge portion at an interface between the plug insert portion and the plate portion, wherein the bridge portion provides structural integrity for the interface. 
 
     
     
       14. The electrical plug arm of  claim 13 , wherein:
 the bridge portion is constructed from cold work. 
 
     
     
       15. The electrical plug arm of  claim 9 , wherein:
 the single material comprises a conductive material. 
 
     
     
       16. An electrical plug arm, comprising:
 a plug insert portion operative to be received into a corresponding electrical receptacle; 
 a plate portion comprising an elongated plate, wherein the plug insert portion extends from a surface of the elongated plate at a first end of the elongated plate, and 
 
       wherein the first end of the elongated plate is sized to correspond to the plug insert portion;
 a bridging portion connecting the plug insert portion to the plate portion, wherein the plug insert portion, the plate portion, and the bridging portion are constructed from a single piece of material; and 
 a pin for connecting the plug arm to a lead, the pin extending from a second end of the elongated plate, wherein:
 the second end of the elongated plate is sized to correspond to the pin; 
 the second end of the elongated plate is smaller than the first end of the elongated plate; and 
 a primary axis of the pin is perpendicular to a plane of the largest surface of the plate portion. 
 
 
     
     
       17. The electrical plug arm of  claim 16 , wherein:
 the plate portion is constructed from cold work. 
 
     
     
       18. The electrical plug arm of  claim 16 , wherein the plug insert portion further comprises:
 a plug end; and 
 a stem connecting the plug end to the bridging portion, wherein a cross-section of the stem is smaller than a cross-section of the plug end. 
 
     
     
       19. The electrical plug arm of  claim 16 , wherein:
 the single piece of material comprises a metal. 
 
     
     
       20. An electrical plug, arm comprising:
 a plug insert portion operative to be received into a corresponding electrical receptacle; 
 a plate portion comprising an elongated plate, wherein the plug insert portion extends from a surface of the elongated plate at a first end of the elongated plate, and 
 
       wherein the first end of the elongated plate is sized to correspond to the plug insert portion;
 a bridging portion connecting the plug insert portion to the plate portion, wherein the plug insert portion, the plate portion, and the bridging portion are constructed from a single piece of material; and 
 a pin for connecting the plug arm to a lead, the pin extending from a second end of the elongated plate, wherein:
 the second end of the elongated plate is sized to correspond to the pin; and 
 the second end of the elongated plate is smaller than the first end of the elongated plate, wherein the plug insert portion further comprises: 
 a plug end; and 
 a stem connecting the plug end to the bridging portion, wherein a cross-section of the stem is smaller than a cross-section of the plug end, 
 a front cap molded over the stem, wherein a cross-section of the front cap is not larger than the cross-section of the plug end.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to U.S. Provisional Application No. 61/110,474, filed Oct. 31, 2008, which is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     This is directed to providing an electric plug constructed from a single piece of material using a cold working process. 
     Power adapters include two or more plug arms that extend from a body to interface with wall sockets. To provide power from the arms to an electronic device, the power adapter can include one or more cables connecting the arms to an adapter operative to engage the electronic device. The arms can connect to the cables using any suitable approach, including for example via a pin that is soldered to the cables. As another example, a pin can be inserted in a circuit board operative to transform and direct power to the cables. 
     Some power adapters can include additional connectors or components for providing enhanced functionality. For example, some power adapters can include one or more USB, FireWire, 30-pin, or other connectors. The connectors can be fully integrated in the power adapters to provide a compact component that the user can easily carry and use. Integrating other connectors or components in a power adapter can restrict the space available for the arms to connect to the cables. In particular, if a connector is positioned immediately behind an arm, there may be insufficient space to route a cable around the connector to connect to the arm, or the connector can prevent substantially all direct access to the arm. 
     To accommodate the connector while retaining a small profile, one or more of the arms can include a plate extending from the base of the arm and providing a conductive path to a pin used for connecting to cable. The plate can be coupled to the arm and pin using any suitable approach. For example, the plate can be coupled to the arm using a screw, mechanical fastening mechanism (e.g., a pin passing through an opening and expanding), welding, soldering, or other coupling mechanism. While these approaches may allow an electrical current to pass from the arm to the pin, the inherent weakness due to connecting two distinct components together can cause the power adapter to fail. 
     SUMMARY OF THE INVENTION 
     This is directed to a power adapter plug arm having an integral plate for conducting power to a pin. The arm and plate can be constructed from a single piece of material using a bending and cold heading process. 
     The power adapter plug arm can include a plug operative to extend into a wall socket. The particular dimensions of the plug can be defined using any suitable standard, including for example the national standards agency of individual countries. A plate substantially perpendicular to the plug can be coupled to the end of the plug (e.g., the end that is not inserted into the wall socket) to provide a path between the plug and a cable extending from the power adapter. The plate can be substantially elongated, and positioned such that the plug extends from a first end of the plate and a pin connecting the plug to a circuit board extends from a second end of the plate. To increase the strength of the arm, the plug and plate can be constructed using a cold working process using a single piece of material, such as a single piece of brass or steel. 
     Any suitable manufacturing process or combination of manufacturing processes can be used to manufacture a power adapter arm from a single piece of material (e.g., brass or steel). In some embodiments, a block of material can first be drawn through a die to form a rectangular bar. The bar can be milled to form the power adapter plug, and lathed to form a tubular stem extending from the power adapter plug such that the plug and stem are substantially co-axial. To form the plate, the tubular stem may be bent, for example substantially perpendicular to the plug axis. The bent stem can be cold headed to flatten the stem and form a substantially flat plate. The plate can then be grinded or machined to shape the periphery of the plate, and a pin can be coupled to the opposite end of the plate such that it extends from the opposite surface of the plate as the stem and plug. Once the final shape has been reached, the arm can be finished for aesthetic purposes, for example using sand blasting and nickel plating. By bending the stem and cold heading the bent stem, the strength of the plate-stem interface (e.g., the strength of a bridging portion connecting the stem to the plate) can be increased by cold work, thus further improving the stiffness and strength of the power adapter arm and reducing failures due to fatigue use. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features of the present invention, its nature and various advantages will be more apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is an exploded view of an illustrative power adapter having a plug arm formed from a single piece of material in accordance with one embodiment of the invention; 
         FIG. 1A  is a perspective view of an illustrative power adapter having a plug arm formed from a single piece of material in accordance with one embodiment of the invention; 
         FIGS. 2A and 2B  are perspective views of an illustrative plug arm for use in a power adapter in accordance with one embodiment of the invention; 
         FIG. 3A  is a schematic view of a cold draw operation in accordance with one embodiment of the invention; 
         FIG. 3B  is a schematic view of a lathing operation for creating a stem in accordance with one embodiment of the invention; 
         FIG. 3C  is a schematic view of a cold heading operation for shaping a plug in accordance with one embodiment of the invention; 
         FIG. 3D  is a schematic view of an illustrative bending process for defining the end of the stem in accordance with one embodiment of the invention; 
         FIG. 3E  is a schematic view of an illustrative cold heading process for forming a plug arm plate in accordance with one embodiment of the invention; 
         FIG. 3F  is a schematic top view of an illustrative finished plug arm plate in accordance with one embodiment of the invention; 
         FIG. 3G  is a schematic view of an illustrative process for shaping the stem in accordance with one embodiment of the invention; and 
         FIG. 4  is a flowchart of an illustrative process for manufacturing a power adapter arm from a single piece of material in accordance with one embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a an exploded view of an illustrative power adapter having a plug arm formed from a single piece of material in accordance with one embodiment of the invention. Power adapter  100  can include ground plug arm  112 , first AC plug arm  114  and second AC plug arm  116 . The plug arms can be retained by front cap  120 , which can serve as an exterior surface of power adapter  100 . In particular, front cap  120  can include cosmetic surface  121  that may be visible to a user when power adapter  100  is assembled. Front cap  120  can include openings  122 ,  124  and  126  for receiving each of plug arms  112 ,  114  and  116 , respectively. In some embodiments, front cap can include protrusions  125  and  127  extending beyond the surface of cosmetic surface  121 . The size and length of protrusions  125  and  127  can be selected based on any suitable criteria, including for example the dimensions and shapes of AC plug arms  114  and  116 , and standards set for power adapters by various national or international bodies. Plug arms  112 ,  114  and  116  can be placed in front cap  120  using any suitable approach. For example, front cap  120  can be molded over plug arms  112 ,  114  and  116 , for example as shown in  FIG. 1A . As another example, the shape and sizes of plug arms  112 ,  114  and  116  can allow the plug arms to be inserted into the corresponding openings of front cap  120 , for example from cosmetic surface. 
     Each of plug arms  112 ,  114  and  116  can be connected to particular portions of circuit board  130 . For example, circuit board  130  can include leads operative to direct power from a remote source (e.g., a wall socket) to an electronic device requiring power. Power adapter  100  can connect to an electronic device using any suitable approach, including for example via connector  132 . Connector  132  can include any suitable type of electronic connector that supports the transfer of power, including for example a USB, AT, SATA, Molex, Firewire, PCI, or any other suitable powered connector. In some embodiments, circuit board  130  can instead or in addition include wires or cables directly connecting the circuit board to the electronic device. The components of circuit board  130 , including the leads for receiving each of plug arms  112 ,  114  and  116  can be distributed based on any suitable criteria, including for example based on space considerations (e.g., to minimize the size of power adapter  100 ). In some embodiments, the distribution of circuit board components can require one or more the leads for receiving each of plug arms  112 ,  114  and  116  to be positioned away from the portions of plug arms  112 ,  114  and  116  that extend from front cap  120 . In particular, the leads can be located such that each of plug arms  112 ,  114  and  116  cannot simply extend in the same axis as the plug arm to connect to the circuit board, but require a bridging portion to connect the plug arm to the circuit board (e.g., as shown in plug arms  114  and  116 ). 
     Power adapter  100  can include enclosure  140  for receiving circuit board  130  and protecting the circuit board components from damage due to the environment. In addition, enclosure  140  can be electrically isolating to prevent electrical charges from travelling from the wall socket to plug arms  112 ,  114  and  116 , and to the user&#39;s hand. Enclosure  140  can be constructed from any suitable material, including for example plastic, a ceramic material, or any other suitable isolating material. Enclosure  140  can include opening  142  for providing access to connector  132 . Enclosure  140  can include lip  144  operative to receive front cap  120  to assemble power adapter  100 . Front cap can be coupled to enclosure  140  using any suitable approach, including for example an adhesive (e.g., placed on lip  144 ), a press fit, interlocking features of the front cap and enclosure (e.g., tabs extending into corresponding slots), a mechanical fastener, welding (e.g., ultrasonic welding), or any other suitable approach. 
     When, due to space or other considerations, a plug arm includes a bridging portion, additional stresses can be introduced in the power adapter. In particular, the connection between the plug stem and the plate forming the bridging portion can be at a large angle (e.g., substantially a perpendicular connection), and the length of the plate can create a large aspect ratio relative to the stem, which can combine to generate a significant bending moment. Then, forces applied to the plug arm during normal use (e.g., as a user manipulates the power adapter to plug it into a wall socket) can be transferred to the plate-plug interface and cause fatigue or other stresses. 
     To ensure that the plug stem-plate connection can resist the applied stresses, the plug arm can be constructed from a single piece of material.  FIGS. 2A and 2B  are perspective views of an illustrative plug arm for use in a power adapter in accordance with one embodiment of the invention. Arm  200  can include plug  210  operative to be inserted in a power socket. Plug  210  can have any suitable dimension (e.g., 4.0 mm×8.70 mm×6.30 mm), including for example dimensions set by national or international standards agencies. In the example of  FIGS. 2A and 2B , plug  210  corresponds to the plugs used in the United Kingdom, though it will be understood that any other suitable plug dimension can be used. Plug  210  can include tip  212  that can be tapered, body  214 , and end  216 . Stem  220  can extend from end  216  in substantially the same axis as plug  210 . In some embodiments, arm  200  may not include stem  220 , but plug  210  may instead extend the combined lengths of plug  210  and stem  220  (e.g., if the plug standard does not include a stem covered by non-conductive material, such as in the United States). Stem  220  can have any suitable dimensions, including for example a length set by a standards body (e.g., 10.0 mm length). In some embodiments, stem  220  can have a smaller cross-section than plug  210  such that a layer of a second material can be placed around the periphery of stem  220  without extending past the boundary of plug  210  (e.g., protrusion  127 ,  FIG. 1 , fits around the stem). Stem  220  can have any suitable cross-section, including for example a circular cross-section, a rectangular cross-section, a cross-section matching or substantially similar to the cross-section of plug  210 , or any other suitable cross-section. In some embodiments, the cross-section of stem  220  can be selected based on manufacturing criteria, including for example to ensure that a front cap molded over stem  220  properly adheres to the stem sidewalls (e.g., requiring a rectangular or polygonal cross-section instead of a circular cross-section). 
     Arm  200  can include plate  230  coupled to the end of stem  220  such that stem  220  extends from first surface  232  of plate  230 . The plane of plate  230  can be angled relative to the axis of plug  210  and stem  220 . For example, plate  230  can be substantially perpendicular to the axis of plug  210  and stem  220 . In some embodiments, the angle may be at least 45 degrees, so that the aspect ratio of plate  230  and plug  210  is relatively large. Plate  230  can be coupled to stem  220  using any suitable component, including for example a bridging portion constructed from the same piece of material as arm  200  (e.g., bridging portion  231 ). Plate  230  can have any suitable thickness, periphery, or other characteristic length. For example, plate  230  can be 1.0 mm thick, and the components extending from plate  230  can be centered at opposite corners of a 13.23 mm×12.55 mm rectangle. In some embodiments, the thickness and periphery of plate  230  can be selected based on constraints set by the components on a circuit board, or constrains in the top cap or in the top cap manufacturing. 
     In some embodiments, plate  230  can be substantially elongated such that stem  220  extends from a first end of plate  230 . Plate  230  can include aperture  236  at a second end of plate  230  that is opposite the first end. Pin  240 , which can extend from second surface  234  of plate  230  (e.g., extend from the opposite surface as stem  220 ), can be operative to engage or electrically connect with a circuit board of the power adapter (e.g., circuit board  130 ,  FIG. 1 ). Pin  240  can have any suitable cross-section (e.g., diameter) or length, including for example a diameter and length determined by the distance between arm  200  and the circuit board, and the size of the opening or port in the circuit board for receiving pin  240 . Pin  240  can extend from plate  230  at any suitable angle, including for example substantially perpendicular to the plane of plate  230 , substantially in the same orientation as stem  220 , or at any other suitable angle. Pin  240  can be coupled to plate  230  using any suitable approach, including for example by inserting pin  240  into aperture  236  and fastening the pin (e.g., using a rivet), with a mechanical fastener (e.g., a screw), soldering, swaging, welding, an adhesive, or any other suitable coupling mechanism. In some embodiments, the coupling mechanism can be selected to ensure that power or other signals can propagate from plate  230  into pin  240 . 
     Any suitable process or combination of processes can be used to construct arm  200  from a single piece of material. For example, a sequence of cold-working processes can be used to form arm  200 .  FIGS. 3A-3G  are schematic views of successive cold-working operations that can be used to manufacture a power adapter plug arm in accordance with one embodiment of the invention.  FIG. 3A  is a schematic view of a cold draw operation in accordance with one embodiment of the invention. As shown in  FIG. 3A , block  302  of material, for example a block of brass or steel can be drawn through die  304  to create bar  306 . Bar  306  can have any suitable dimension, including for example substantially the final dimension of an electrical plug. Once the bar is formed, the stem can be defined.  FIG. 3B  is a schematic view of a lathing operation for creating a stem in accordance with one embodiment of the invention. Bar  306  can be placed in a lathe and cut to create stem  308 . The length of stem  308  can be selected based on any suitable criteria, including for example the final lengths of stem and plate required for the arm, the length of the plug, combinations of these, or any other suitable criteria. Once the stem has be constructed, bar  306  can be placed in carrier  310  such that a portion of bar  306  extends from the top surface of carrier  310 , while the stem remains underneath the top surface of carrier  310  (e.g., as shown in  FIG. 3C ). In some embodiments, bar  306  can be placed in carrier  310  prior to or as part of the lathing operation. Once the stem has been formed, the plug can be shaped.  FIG. 3C  is a schematic view of a cold heading operation for shaping the plug in accordance with one embodiment of the invention. In some embodiments, the portion of bar  306  that will form the plug can be exposed in carrier  310  so that tool  312  can be applied to the exposed portion of bar  306 . Tool  312  may be operative to define the basic geometry of plug  309 , trim or stamp particular head features, or perform any other suitable operation (e.g., cutting, milling, compressing, or bending) to finalize the plug shape. In some embodiments, tool  312  can perform a cold head strike to shape plug  309 , or instead or in addition be used in a forging, trimming, or stamping operation. Although the order of  FIGS. 3B  and  3 C show stem  308  created before plug  309 , it will be understood that the order of these processes is purely illustrative and can be changed without departing from the invention. 
     Once the plug has been formed, the plate that is coupled to the end of the plug can be constructed.  FIG. 3D  is a schematic view of an illustrative bending process for defining the end of the stem in accordance with one embodiment of the invention. Bar  306  can be moved in carrier  310  (or to a different carrier) such that bar  306  is retained in the carrier by stem  308 . The distance between the base of stem  308  and carrier  310  (e.g., the top or bottom surface of carrier  310 ) can be selected based on any suitable criteria, including for example electrical plug standards defined by appropriate organizations (e.g., so that the stem length, or combined plug and stem length is a predetermined length). The portion of stem  308  extending beyond the top surface of carrier  310  can be bent to place the material  314  that will become the plug arm plate. The bent portion of stem  308  (e.g., material  314 ) can have any suitable length, including for example at least half of the length of stem  308  and plug  309 , substantially the same length as stem  308  and plug  309 , or longer than the length of stem  308  and plug  309 . Stem  308  can be bent at any suitable angle, including for example substantially perpendicular to the axis of plug  309 . To ensure that stem  308  is bent by the proper amount, stem  308  can be bent until it is substantially flush with the top surface of carrier  310 . Thus, the relative angle between stem  308  and carrier  310  can be used to accurately define the angle between stem  308  and material  314 . 
     To shape substantially round (e.g., lathed) material  314  into the flat plate of the plug arm, another cold heading operation can be performed.  FIG. 3E  is a schematic view of an illustrative cold heading process for forming a plug arm plate in accordance with one embodiment of the invention. Tool  320  can be applied to material  314 , which can be substantially circular or elliptical, to form substantially flat plate  316  having a proximal end adjacent to the bending location and a distal end adjacent to the free end of the bent material. Tool  320  and carrier  310  can be designed to interface in a manner to ensure that plate  316  has any suitable width (e.g., 1 mm) and any suitable periphery. For example, tool  320  can include a die to trim portions of plate  316  that extend beyond a desired periphery or dimensions. By using tool  320  to provide a cold head strike on material  314 , the crystal properties of material  314  can be re-aligned to relieve stresses created when stem  308  was bent, and strengthen bridging portion  317  between the end of stem  308  and plate  316 . The cold heading can therefore provide a stronger interface than coupling a separate stem and plate together, while providing an efficient manufacturing process. 
     Once plate  316  has the appropriate width, plate  316  can be processed to refine the shape of the plate, punch one or more holes for receiving a pin (e.g., pin  240 ,  FIG. 2 ), and remove or erase manufacturing marks (e.g., marks due to carrier  310 ).  FIG. 3F  is a schematic top view of an illustrative finished plug arm plate in accordance with one embodiment of the invention. Plate  316  can include any suitable shape, including for example expanded portion  318  adjacent to bridging portion  317  and elongated portion  319  extending to the opposite end of plate  316 . In some embodiments, a punching process can be performed to create aperture  322  (e.g., for a pin). After plate  316  has been finished, stem  308  can be re-shaped to provide a cross-section or sidewalls better suited to adhere to material molded around stem  308  and arm  300 .  FIG. 3G  is a schematic view of an illustrative process for shaping the stem in accordance with one embodiment of the invention. Tool  324  can be applied to stem  308  to refine the shape of stem  308  using any suitable approach, including for example removing some or all curved surfaces of stem  308 , or compressing or cutting portions of stem  308 . It will be understood that the steps or processes shown in  FIGS. 3A-3G  are merely illustrative, and that other processes can be used instead or in addition of those shown (e.g., couple the pin to the end of plate  316 , and include sand blasting and nickel plating processes), and the order of the processes is merely illustrative and can be changed to suit any suitable purpose. 
       FIG. 4  is a flowchart of an illustrative process for manufacturing a power adapter arm from a single piece of material in accordance with one embodiment of the invention. It will be understood that the order of steps in process  400  is merely illustrative, and that particular steps can be removed or added without departing from the invention. Process  400  can begin at step  402 . At step  404 , the material used for the power adapter arm can be drawn through a die. For example, a brass or steel block can be drawn through a die to create a rectangular bar. The cross-section of the drawn bar can be substantially the same as the cross-section of the plug used in a power adapter (e.g., the drawn block could be inserted in a wall outlet). In some embodiments, the die can define other shapes for the drawn block, including for example circular or oval cross-sections (e.g., based on the set dimensions of electrical plugs for the market in which the arm is to be used). At step  406 , a first portion of the drawn material can be milled, worked, machined, or combinations of these and other processes to form the power adapter plug. For example, a first end of the block can be milled to form the plug. The milling, working or machining process can remove any suitable amount of material, including for example sufficient material for the remaining plug to satisfy the specifications set by an appropriate standards agency for electrical plugs. 
     At step  408 , the end of the bar opposite the plug can be lathed to form an elongated tubular structure extending from the base of the plug, and substantially along the same axis as the plug. The tubular structure can define a stem having a length at least equal to the sum of lengths of the plug adapter stem and plate. The stem can have any suitable diameter or other characteristic length (e.g., if the stem has an elliptical cross-section). In particular, the diameter or characteristic length can be selected such that the volume of material is sufficient to form a plate having suitable dimensions when compressed (e.g., the volume of the stem is at least equal to the volume of the plate). Although this process describes the stem as being circular, it will be understood that the stem can have any suitable cross-section or other characteristic dimension (e.g., a rectangular cross-section). At step  410 , the stem can be bent. For example, a press can be used to bend the stem to any suitable angle. In particular, the angle can be selected based on space requirements or other constraints within the power adapter (e.g., a substantially right angle, or any other angle based on the relative positions of the arm and other components in the power adapter). The stem can be bent at any suitable distance from the plug, including for example at a minimal distance for allowing another material to be molded over the stem (e.g., 10 mm). As another example, the stem can be bent at a distance from the plug such that the bent portion of the stem is at least equal to the length of the plate. As still another example, the stem can be bent at a distance from the plug defined by a standards agency. 
     At step  412 , the bent portion of the stem can be cold headed or cold worked to flatten the bent portion of the stem and form a plate. The tool used for the cold heading process can include a die to substantially shape the plate (e.g., remove excess material during the cold heading to define the periphery of the plate). The force applied during the cold heading process and the die properties can be selected based any suitable criteria, including for example to provide a plate having a thickness within a desired range (e.g., 1 mm). At step  414 , the plate can be machined, worked or ground to refine the shape of plate. For example, the plate can be trimmed to define the final periphery of the plate, one or more holes can be drilled or punched, tooling or fixture marks can be removed (e.g., by polishing the plate), or any other finishing process can be applied. 
     At step  416 , the stem can be machined to provide surfaces better adapted to adhering to a material molded over the arm. For example, the rounded stem can be machined to create a substantially rectangular stem. In some embodiments, if the stem created at step  408  has sufficient surfaces to adhere to the molded material, step  416  can be skipped. At step  418 , a pin can be coupled to the end of the plate. For example, a pin can be placed in a hole drilled at the end of the plate and fixed using a mechanical fastener (e.g., rivet or a screw) or a material deforming process (e.g., staking). The pin can extend from the opposite end of the plate as the stem and plug, and extend from the opposite surface of the plate. In some embodiments, the manufactured arm can then be finished, for example for aesthetic purposes (e.g., sand blasted and nickel plated). Process  400  can then end at step  420 . 
     The above-described embodiments of the present invention are presented for purposes of illustration and not of limitation, and the present invention is limited only by the claims which follow.

Metadata:
Filing Date: 20090130
Publication Date: 20110920
Grant Date: 20110920
Priority Date: 20081031
Inventors: EARLY MALCOLM
CONNORS BRANDON
WALSH KEVIN
Assignee: APPLE INC
CPC Classifications: [{"code": "Y10T29/49153", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y10T29/49153", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R43/16", "inventive": true, "first": true, "tree": "[]"}, {"code": "Y10T29/49151", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y10T29/49218", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y10T29/49151", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y10T29/49204", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y10T29/4914", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/665", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T29/49181", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R43/16", "inventive": true, "first": true, "tree": "[]"}, {"code": "Y10T29/49204", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y10T29/49217", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y10T29/49217", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/665", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T29/49181", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R24/22", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R2103/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R2103/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R24/22", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T29/4914", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y10T29/49218", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 42131963