PATENT DOCUMENT

Publication Number: US-9281612-B2
Application Number: US-201314029705-A
Country: US
Kind Code: B2

Title: Magnetic connector having a unitary housing

Abstract:
Power cables that include plug housings having an improved appearance as well as employ a halogen-free cable while providing adequate fire resistance. One example provides a power cable having cable plug with a substantially unitary body. Another example provides a power cable that is formed using halogen-free materials. To provide adequate fire protection, a strain relief formed using multiple materials is used.

Claims:
What is claimed is: 
     
       1. A power cable assembly comprising:
 a cable plug comprising a cylindrical housing having a first circular end and a second circular end, and a first opening at the first end and a second opening on a side of the cylindrical housing, the second opening spaced away from the first end and the second end; and 
 a cable including a power conductor and a ground conductor and entering the cable plug at the first opening at the first end of the cylindrical housing, the cable plug further comprising 
 a plurality of contacts each having a portion beyond the second opening in the side of the cylindrical housing such that contact may be made with opposing contacts in a compatible connector receptacle; 
 a light-emitting diode; and 
 a magnetic element located at least between the plurality of contacts and the second end of the cylindrical housing. 
 
     
     
       2. The power cable assembly of  claim 1  wherein the cylindrical housing is formed using plastic. 
     
     
       3. The power cable assembly of  claim 1  wherein the cylindrical housing is substantially unitary. 
     
     
       4. The power cable assembly of  claim 1  wherein the magnetic element comprises an attraction plate. 
     
     
       5. The power cable assembly of  claim 1  wherein each of the plurality of contacts pass through the second opening in the side of the cylindrical housing and extend beyond the cylindrical housing. 
     
     
       6. The power cable assembly of  claim 4  wherein when the cable plug is inserted in a compatible connector receptacle the magnetic element in the cable plug is magnetically attracted to a magnet in the connector receptacle. 
     
     
       7. The power cable assembly of  claim 1  wherein the magnetic element comprises a magnet. 
     
     
       8. The power cable assembly of  claim 7  wherein when the cable plug is inserted in a compatible connector receptacle the magnetic element in the cable plug is magnetically attracted to a magnet in the connector receptacle. 
     
     
       9. The power cable assembly of  claim 8  wherein the cylindrical housing is formed using plastic. 
     
     
       10. A cable plug comprising:
 a cable having a power conductor and a ground conductor; 
 an assembly comprising a nonconductive insulative housing and power and ground conductors, the power and ground conductors of the assembly terminating in a first and second contact, the first contact coupled to the power conductor of the cable and the second contact coupled to the ground conductor of the cable; 
 a plurality of contacts including the first contact and the second contact and located in passages in the assembly and each having a contact portion such that contact may be made with opposing contacts in a compatible connector receptacle; 
 a light emitting diode; 
 a magnet between the plurality of contacts and an end of the cable plug; and 
 a cylindrical housing enclosing at least a portion of the assembly and light emitting diode, the cylindrical housing having a circular first end and a circular second end. 
 
     
     
       11. The cable plug of  claim 10  wherein the cylindrical housing is unitary. 
     
     
       12. The cable plug of  claim 10  wherein the cylindrical housing includes a first opening at a first end, where the cable enters the cable plug at the first opening. 
     
     
       13. The cable plug of  claim 10  wherein the contacts are fixed contacts. 
     
     
       14. The cable plug of  claim 10  wherein the contacts comprise a center contact, two ground contacts, and two power supply contacts. 
     
     
       15. The cable plug of  claim 14  wherein the power supply contacts are on each side of the center contact, and the ground contacts are on each side of the power supply pins away from the center contact. 
     
     
       16. A cable plug comprising:
 an insulative housing having a first circular end and a second circular end; 
 a printed circuit board; 
 a cable including a power conductor and a ground conductor, the power conductor and ground conductor coupled to the printed circuit board; 
 a plurality of contact pins having a contact portion extending beyond the housing such that contact may be made with opposing contacts in a compatible connector receptacle, the contact pins having tail portions soldered to the printed circuit board; 
 a light-emitting diode fixed to the printed circuit board; and 
 an attraction plate attached to the housing, the attraction plate spaced away from the first circular end and the second circular end and having an opening for a contact portion of at least one of the plurality of contact pins, 
 wherein the insulative housing is a substantially cylindrical housing having a first opening for the cable and a second opening for at least one of the plurality of contact pins, the attraction plate and cylindrical housing substantially enclosing the plurality of contacts, the printed circuit board, and the light-emitting diode. 
 
     
     
       17. The cable plug of  claim 16  wherein the insulative housing includes a third opening for light emitted by the light-emitting diode. 
     
     
       18. The cable plug of  claim 16  wherein the cable plug further comprises a metal tab formed from an end of the ground conductor. 
     
     
       19. The cable plug of  claim 16  wherein the contact pins comprise spring-biased pins. 
     
     
       20. The cable plug of  claim 16  wherein the contact pins comprise a center pin, two ground contact pins, and two power supply contact pins. 
     
     
       21. The cable plug of  claim 20  wherein the power supply contact pins are on each side of the center pin, and the ground contact pins are on each side of the power supply pins away from the center pin.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 12/582,308, filed Oct. 20, 2009, now U.S. Pat. No. 8,535,088, entitled “MAGNETIC CONNECTOR HAVING A UNITARY HOUSING”, which is incorporated by reference. 
    
    
     BACKGROUND 
     Portable electronic devices have become increasingly popular the past several years. Laptop and netbook computers, cell phones, portable media devices, and the like have become ubiquitous, and soon notebook and tablet computing devices will follow. 
     These devices include batteries that provide power. Unfortunately, these batteries need recharging. This recharging is often performed using a power cable having a connector insert or cable plug that mates with a connector receptacle on the portable device. Power can be supplied by a power transformer that receives power from a wall outlet, vehicle charging outlet, or other source. The power transformer converts the power from the outlet to a power level that can be used to charge the battery in a portable device. In some circumstances, these power cables may also convey signals between the portable device and a second electronic device. 
     The connector insert or cable plug may include circuitry inside of a plug housing. The plug housing typically is formed using several pieces that fit together around the circuitry. This patchwork of pieces used to form a plug housing can result in a housing having a less than optimal appearance. 
     The cable can include a conductor surrounded by an insulating layer. This conductor can be used to convey a power supply, such as a positive power supply voltage. The insulating layer can be further surrounded by a metallic braid layer that is used to convey ground. The braiding may be covered with a polyvinyl chloride coating. This coating provides a fire resistance to protect the electronic device in the event that the power transformer overheats or catches on fire. However, for various reasons, it is environmentally undesirable to use materials such as polyvinyl chloride. Unfortunately, halogen-free cables do not provide adequate fire resistance. 
     Thus, what is needed are improved power cables that have plug housings that provide an improved appearance as well as employ a halogen-free cable while providing adequate fire resistance. 
     SUMMARY 
     Accordingly, embodiments of the present invention provide power cables that include cable plug housings having an improved appearance as well as employing a halogen-free cable while providing adequate fire resistance. 
     A specific embodiment of the present invention provides a power cable having a cable plug or connector insert with a unitary (made from a single piece) or substantially unitary body. This body provides an improved appearance, greater strength and durability, and is simple to manufacture at a reduced cost. The cable plug can receive a power cable and may provide contacts for power transmission. The housing may be substantially unitary, that is, it may be made predominantly using a single piece of material. The single piece of material may be formed using metal, such as aluminum. The single piece of material may alternately be formed using plastic, ceramic, or other material. The single piece may be approximately cylindrical, or it may have other shapes, such as oval, square, or other shapes or combinations of shapes. 
     The contacts or terminals may extend from the cable plug housing and may be protected by a protrusion that mates with a connector receptacle on an electronic device. In various embodiments of the present invention, the protrusion is a magnetic element that is attracted to a second magnetic element in the connector receptacle. These magnetic elements may be magnets, attraction plates, or other types of magnetic elements, such as electromagnets. The attraction plates may be formed using a ferromagnetic material. In a specific embodiment of the present invention, the connector insert protrusion can include an attraction plate that is attracted to a magnetic element located in the connector receptacle. 
     Another specific embodiment of the present invention provides a power cable that is formed using halogen-free materials. To provide adequate fire protection, a strain relief formed using multiple materials is used. This strain relief can provide an interface between the cable and a housing, for example, a housing enclosing a power transformer. The strain relief can include a first, interior portion formed using a rigid, fire-resistant material. The fire-resistant material may be a polycarbonate, polycarbonate ABS (PC/ABS) blend, or other appropriate material. The strain relief may include a second, exterior portion formed using a flexible material. This material may be a thermoplastic elastomer (TPE), fluorinated ethylene propylene (FEP), or other appropriate material. 
     Various embodiments of the present invention may incorporate one or more of these and the other features described herein. A better understanding of the nature and advantages of the present invention may be gained by reference to the following detailed description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a power cable assembly according to an embodiment of the present invention; 
         FIG. 2  illustrates a cable plug according to an embodiment of the present invention; 
         FIG. 3  illustrates components that may be used to construct a cable plug according to an embodiment of the present invention; 
         FIG. 4  illustrates a side view of a portion of a cable plug according to an embodiment of the present invention; 
         FIG. 5  illustrates portions of a strain relief according to an embodiment of the present invention; and 
         FIG. 6  illustrates a strain relief according to an embodiment of the present invention. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       FIG. 1  illustrates a power cable assembly  100  according to an embodiment of the present invention. This figure, as with the other included figures, is shown for illustrative purposes and does not limit either the possible embodiments of the present invention or the claims. 
     Power cable assembly  100  may be used for providing power to an electronic device, such as a laptop, netbook, notebook, tablet computer, media player, portable media player, cell phone, or other type of electronic device. Cable assembly  100  may also be used to convey signals between such devices. Cable assembly  100  may include cable plug  105  and strain relief  140  connected together via cable  150 . 
     Cable plug  105  may mate with a compatible connector receptacle (not shown.) Cable plug  105  may include housing  110 , attraction plate  125 , and strain relief  115 . Housing  110  may be unitary or substantially unitary. This unitary construction can provide a connector plug  105  having an improved appearance, increased strength, and reduced manufacturing costs. Housing  110  may be formed using metal, such as aluminum, plastic, ceramic, or other material. 
     Attraction plate  125  may be formed around contacts  130 . Attraction plate  125  may have two axes of symmetry, allowing cable plug  105  to mate with a compatible connector receptacle in at least two orientations. Attraction plate  125  may be formed of metal, plastic, ceramic, or other material. For example, the attraction plate may be made using a ferromagnetic material. 
     A dust cover (not shown) may cover the sides of attraction plate  125  and the contacts  130 . The dust cover may be formed using metal, plastic, ceramic, or other material. For example, it may be formed of a transparent plastic. The dust cover may form a seal, reducing or eliminating the amount of dust particles entering housing  110  when cable assembly  100  is transported. To prevent the loss of the dust cover, the dust cover may be attached to the cable assembly  100  by a tie, cord, wire, or other fastener. 
     Contacts  130 , which may also be referred to as signal terminals or pins, may include contacts for signal and power supplies, such as power and ground. Cable plug  105  can include five such contacts, though in other embodiments of the present invention, other numbers of contacts may be included. For example, three contacts may be included. Also in other embodiments of the present invention, one or more contact for fiber-optic cables may be included. The center pin may be a detect pin that detects that cable plug  105  has mated with a compatible connecter receptacle. Two ground pins may be located on each side of the detect pin. Two power supply pins may be located on each side of the detect pin between the detect pin and the ground pins. Alternately, the ground pins may be located between the power supply pins and the detect pin. The contacts may be retractable, that is, they may be biased, for example by a spring. 
     Cable plug  105  can include a strain relief  115 . Strain relief  115  may be formed of a flexible material. For example, it may be made of a halogen-free material. In a specific embodiment of the present invention, it can be formed using a thermoplastic elastomer, fluorinated ethylene propylene, or other appropriate material. 
     Strain relief  140  and cabling  152  can form a pigtail that may be used to connect power cable assembly  100  to a power supply. For example, the pigtail may be housed in an enclosure that includes a power transformer or other circuitry. For example, the enclosure may have power prongs or other connections to receive power from a wall socket, vehicle outlet, or other power supply. Circuitry internal to the housing can convert the received power supply to a power level appropriate for the electronic device to be charged. Cabling  152  may connect to this power conversion circuitry, such as a power transformer that converts AC power to DC power. Alternately, cabling  152  may connect to power conversion circuitry that converts a first DC power supply to a second DC power supply. The housing may also include wired or wireless data communications and other electronic circuits. Cabling  152  may include further connections for these circuits. 
     Strain relief  140  can include an interior portion  145  and exterior portion  147 . Interior portion  145  may be inside the housing (not shown) that also includes the power transformers or other electrical components. Exterior portion  147  may be located outside of this housing. Inside portion  145  may be formed using a hard plastic, such as a polycarbonate, polycarbonate ABS blend or other appropriate material, for fire protection. Exterior portion  147  may be formed using a more flexible material, such as a thermoplastic elastomer, fluorinated ethylene propylene, or other appropriate material. 
     Strain relief  140  may provide an interface between cable  150  and the housing. Strain relief  140  can allow cable  150  to be flexed or moved relative to the housing, such that cable  150  does not wear excessively. Strain relief  115  can similarly protect cable  150  at its interface with cable plug  105 . 
     Cable  150  may be formed with an inside conductor surrounded by a metallic braiding. The inside conductor may be used to convey power, while the braiding may be used to convey ground. Isolation layers may be included between the inside conductor and the braiding, and outside of the cable around the braiding. Cable  150  may be made of a halogen-free material. For example, it may be formed using a thermoplastic elastomer, fluorinated ethylene propylene, or other appropriate material. Cable  150  may include additional conductors for conveying signals, for example, those provided by wired or wireless data communications and other electronic circuits located in the housing that includes the power transformer or conversion circuitry. Cable  150  may also include one or more fiber-optic cables. 
     Again, it is desirable to provide a cable plug  105  having an attractive appearance, and that is durable and easy to manufacture. Accordingly, embodiments of the present invention provide a cable plug  105  having a unitary or substantially unitary housing. An example is shown in the following figure. 
       FIG. 2  illustrates a cable plug  205  according to an embodiment of the present invention. Cable plug  205  may also be referred to as a connector insert. Cable plug  205  can include housing  210 , attraction plate  225 , contacts  230 , and strain relief  215 . Cable  250  can attach to cable plug  205 . Attraction plate  225  can protect contacts  230  and can be magnetically attracted to magnets located in a compatible connector receptacle. A dust cover (not shown) may be employed to prevent particulate matter from entering housing  210  when the cable assembly is transported. Housing  210  may also include a light-emitting diode (LED) exit  212 . Exit  212  may allow light from an LED inside housing  210  to escape. In a specific embodiment of the present invention, a lit LED may indicate that an electrical connection has been made between cable plug  205  and a compatible receptacle (not shown.) 
     Housing  210  may be unitary, though in other embodiments of the present invention it may be substantially unitary. In this example, housing  210  is cylindrical, though in other embodiments of the present invention housing  210  may have other shapes. Housing  210  may provide an attractive appearance, and may be durable and easy to manufacture. Housing  210  may be metallic, plastic, ceramic, or formed using another material. In a specific embodiment of the present invention, housing  210  is made of aluminum. 
     Attraction plate  225  may have two axes of symmetry, allowing cable plug  205  to mate with a compatible connector receptacle in at least two orientations. The attraction plate may be metallic, such that it is attracted to magnets inside the connector receptacle. These magnets may have opposing polarities, such that magnetic field lines that originate in one magnet travel through attraction plate  225  and terminate in a second magnet. Attraction plate  225  can, for example, be formed using a ferromagnetic material. In other embodiments of the present invention, attraction plate  225  may be formed using one or more magnets, such as rare-earth magnets or electromagnets. 
     A dust cover (not shown), may be arranged to cover attraction plate  225  and contacts  230 . The dust cover may be formed using metal, plastic, ceramic, or other material. For example, the dust cover may be made of a transparent plastic. This transparent plastic may be colored to provide a pleasing appearance. 
     Contacts  230  may be pogo pins or other types of contacts. Contacts  230  may include a center contact. The center contact may be a detect pin. Alternately, it may be a fiber-optic connection, signal pin, or other type of contact, signal terminal, or pin. The two contacts  230  on each side of the center pin may convey a positive power supply, though they may alternately convey ground. The two outside contacts  230  may convey ground, though they may alternately convey a positive power supply. Contacts  230  are typically metallic, such that they are conductive. Contacts  230  may be formed using brass, copper, or other metals. 
     Strain relief  215  can protect cable  250  from excessive wear that could otherwise result at the interface with housing  210  when cable  250  is moved or flexed relative to housing  210 . Strain relief  215  may be formed using a flexible material, such as a thermoplastic elastomer, fluorinated ethylene propylene, or other appropriate material. 
     Again, it is desirable that cable plug  205  be robust and simple to manufacture. An example of the components that may be used to construct cable plug  205  according to an embodiment of the present invention is shown in the following figure. 
       FIG. 3  illustrates components that may be used to construct a cable plug  305  according to an embodiment of the present invention. Cable plug  305  may include housing  310 , strain relief  315 , cable  350 , crimping ring  355 , assembly  340 , contacts  330  and  332 , front plate  335 , attraction plate  325 , dust cover  320 , circuit board  360 , LEDs  365 , light pipes  370 , and light insulators  380 . 
     Housing  310  may include an LED exit  312 . LED exit  312  may be an actual hole, or it may be a number of small perforations. In a specific embodiment of the present invention, these perforations may be on the order of 0.03 mm in size. At this size, the individual perforations may not be not visible unless light is emitting through them. Again, housing  310  may be metal, for example aluminum, plastic, ceramic, or it may be made of another material. 
     Strain relief  315  may receive cable  350 . Strain relief  315  can be flexible and may prevent housing  310  from wearing cable  350  as cable  350  moves relative to housing  310  during use. Strain relief  315  may be made of a flexible material, such as a thermoplastic elastomer, fluorinated ethylene propylene, or other flexible material. 
     Cable  350  passes through strain relief  315 . Cable  350  may include a center conductor for providing a positive power supply. Cable  350  may include other conductors, fiber-optic cables, or other signal or power conduits. The center conductor may be insulated and surrounded by a metallic braiding. The metallic braiding may be used to covey ground. The metallic braiding may be further insulated. Various embodiments of the present invention use a halogen-free coating or jacket, such as a coating formed using a thermoplastic elastomer, or other appropriate material. 
     Crimping ring  355  can crimp cable  350 . Crimping ring  355  may be metallic, plastic, or formed using other materials. Crimping ring  355  may prevent cable  350  from splitting due to stresses that may result with usage. Crimping ring  355  may also provide strain relief. In various embodiments of the present invention, crimping ring  355  may connect mechanically and (or) electrically to any or all of the metal braiding of cable  350 , assembly  340 , contacts  345 , or circuit board  360 . 
     Assembly  340  may attach to cable  350  at contacts  345 . For example, the inside conductor and braiding of cable  350  may attach to assembly  340  at contacts  345 . Contacts  345  may be located on each side of a portion of assembly  340 . Assembly  340  may be formed using an insulating material, such that an insulative housing is formed. Contacts  345  may connect to conductive leads internal to assembly  340 , where the conductive leads carry power and ground. Assembly  340  may be substantially made of plastic that is formed around these conductive leads. Assembly  340  may further include a metallic tab  342 , which may be coupled to, or an extension of, one of these conductive leads, for example, the conductive lead carrying ground. Metallic tab  342  may be in contact or close proximity to housing  310 . When housing  310  is metallic, this contact or close proximity can provide an electrical discharge path from housing  310  to ground. This can protect cable plug  305  from electrostatic discharge (ESD), for example, when housing  310  is touched by a user. 
     Contacts  330  and  332  may fit in passages in assembly  340 . Contacts  330  may provide power and ground terminals. For example, inside contacts  330  may provide a positive power supply while outside contacts  330  may provide ground. The passages may be formed at least partly by the conductive leads carrying power and ground, such that power and ground connections to the pins are formed when contacts  330  are inserted into passages in assembly  340 . Contacts  330  may be pogo pins or other types of pins. For example, they may be metallic pins inside of a conductive housing. A spring or other biasing mechanism may be located inside the housing, such that the pins remain in an extended state until cable plug  305  is mated with a compatible connector receptacle. When such mating takes place, the pins may be pushed back or retracted into housing  310 . Contact  332  may be a straight pin that is pushed into a detector circuit when cable plug  305  is mated with a compatible connector receptacle, though in other embodiments of the present invention, contact  332  may also be a pogo pin or other spring-biased contact. 
     Front plate  335  may be used to provide an attractive appearance when the contact portion of cable plug  305  is viewed. Front plate  335  may be plastic or other material and may be formed having a desirable color. For example, the color may match a color of cable  350 , housing  310 , or other component. 
     Attraction plate  325  can be magnetically attracted to magnets in a compatible connector receptacle. For example, magnetic field lines may originate in a first magnet in the compatible connector receptacle, pass through attraction plate  325 , and terminate in a second magnet in the compatible connector receptacle. Attraction plate  325  can be formed using a ferromagnetic metal or other material. In other embodiments of the present invention, attraction plate  325  may be formed using one or more magnets. 
     Dust cover  320  may cover attraction plate  325  during transport of the cable assembly or during other times when cable plug  305  is not inserted in a compatible connector receptacle, providing an improved appearance to cable plug  305 . Dust cover  320  may be metal, plastic, ceramic, or other material. For example, dust cover  320  may be formed of a transparent plastic. Dust cover  320  may also reduce or prevent dust or other particulate matter from entering housing  310  through gaps between housing  310  and attraction plate  325 . To help users avoid losing dust cover  320 , dust cover  320  may be attached to the cable assembly using a cord, tie, wire, or other fixture. 
     Circuit board  360  may fit around assembly  340 . Circuit board  360  may be a printed circuit board, flexible circuit board, or other appropriate circuit board. Circuit board  360  may include detection circuitry that may be triggered by contact detect pin  332 . Contacts  330  and  332  may be soldered to circuit board  360 . Circuit board  360  may be glued or otherwise fixed to assembly  340 . 
     LEDs  365  may be located on circuit board  360 . LEDs  365  may light when contact detect pin  332  is pushed, thereby indicating that cable plug  305  has been mated with a compatible connector receptacle. 
     Light pipes  370  may guide light from LEDs  365 . Light pipes  370  may be made of a transparent material. Light pipes may be colored to give interesting or informative coloring to light emitted by LEDs  365 . Light pipes  370  may be fixed to the inside of housing  310 . 
     Light insulators  380  may be used to prevent stray light from illuminating exits  312 . For example, light between plug portion  320  and housing  310  may otherwise illuminate exit  312 , thereby falsely indicating an electrical connection between cable plug  305  and a compatible connector receptacle. Light insulators  380  may be formed using foam or other opaque material. Light insulators  380  may be fixed to light pipes  370 , housing  310 , circuit board  360 , LEDs  365 , or other appropriate location. 
     In a specific embodiment of the present invention, during assembly, cable  350  may be inserted through housing  310  such that cable  350  emerges from the opening in housing  310  used by contacts  330 . Strain relief  315  and crimping ring  355  may be applied to cable  350 . A center conductor and metallic braiding of cable  350  may be soldered to contacts  345 . Contacts  330  and  332  may be fit in passages in assembly  340 . Circuit board  350 , including LEDs  365 , may be soldered to contacts  330  and  332  and affixed to assembly  340 . Front plate  335  and attraction plate  325  may be attached. This assembly may then fit through the opening in housing  310  as cable  350  is pulled away from housing  310 . The extent to which cable  350  is pulled may be determined by a manufacturing fixture. To facilitate the passage of strain relief  315  through housing  310 , glue may be used. This glue may provide lubrication as strain relief  315  passes through housing  310 . The glue may further act as an adhesive when dry to fix strain relief  315  and cable  350  in place relative to housing  310 . Dust cover  320  may be placed over attraction plate  325  and contacts  330  and  332 . 
     In another embodiment of the present invention, one or more of front plate  335  and attraction plate  325  are attached after assembly  340  and its connected components are fit through the opening in housing  310 . Cable  350  may be inserted through housing  310  such that cable  350  emerges from the opening in housing  310  used by contacts  330 . Strain relief  315  and crimping ring  355  may be applied to cable  350 . A center conductor and metallic braiding of cable  350  may be soldered to contacts  345 . Contacts  330  and  332  may be fit in assembly  340 . Circuit board  350 , including LEDs  365 , may be soldered to contacts  330  and  332  and affixed to assembly  340 . Front plate  335  may be attached at this point, or it may be attached later with attraction plate  325 . Alternately, front plate  335  and attraction plate  325  may be attached at this point, or they may be attached later. This assembly may then fit through the opening in housing  310  as cable  350  is pulled away from housing  310 . The extent to which cable  350  is pulled may be determined by a manufacturing fixture. To facilitate the passage of strain relief  315  through housing  310 , glue may be used. This glue may provide lubrication as strain relief  315  passes through housing  310 . The glue may further act as an adhesive when dry to fix strain relief  315  and cable  350  in place relative to housing  310 . Attraction plate  325  and front plate  335  may be attached at this time, as needed. Dust cover  320  may be placed over attraction plate  325  and contacts  330  and  332 . 
     In another embodiment of the present invention, during assembly, the cable and connected components are fit into the end of housing  310 . Strain relief  315  and crimping ring  355  may be applied to cable  350 . A center conductor and metallic braiding of cable  350  may be soldered to contacts  345 . Contacts  330  and  332  may be fit in assembly  340 . Circuit board  350 , including LEDs  365 , may be soldered to contacts  330  and  332  and affixed to assembly  340 . Contacts  330  and  332  may be retracted, and assembly  340  and its connected components fit into the end of housing  310 . Front plate  335  and attraction plate  325  may be attached before or after insertion. Again, glue may be used as a lubricant when strain relief  315  is inserted into housing  310 . Dust cover  320  may be placed over attraction plate  325  and contacts  330  and  332 . 
     Again, during assembly, light pipes  370  may be fixed to housing  310 . Light insulators  380  may be included to reduce the amount of stray light emitted from exits  312 . An example of this structure is shown in the following figure. 
       FIG. 4  illustrates a side view of a portion of a cable plug  405  according to an embodiment of the present invention. Cable plug  405  may include housing  410  having openings or exits  412 . Light from LEDs  465  may be emitted through exits  412  when cable plug  405  is mated with a compatible connector receptacle (not shown.) Specifically, light from LED  465  may be guided by LED housing  467  towards light pipe  470 . Light pipe  470  may guide the light through opening or exit  412 . Light insulators  480  can prevent stray light inside the connector housing  410  from being emitted through exit  412 . For example, light may seep between housing  410  and attraction plate  420 , thereby appearing to falsely indicate that a connection has been made between cable plug  405  and a compatible connector receptacle. 
     It may be desirable to place a second light pipe in exit  412 . If this is done, it is further desirable that the second light pipe be flush with the surface of housing  410 , such that any ridges or bumps between the second light pipe and housing  410  are reduced or eliminated. 
     Accordingly, in a specific embodiment of the present invention, an adhesive is used to form a second light pipe in exit  412  of housing  410 . The adhesive may be placed in exit  412 . This adhesive may be light curing. Light may be applied to the inside of housing  410  to cure the adhesive. An air flow may be similarly applied to the inside of housing  410 , thereby pushing the adhesive out exit  412  as it is cured. Excess adhesive can then be wiped from the outside of housing  410 , such that the surface of the adhesive is flush with the outside of housing  410 . Light pipes  470  may be attached to these second light pipes formed by the adhesive. 
     Again, it is desirable to use halogen-free materials in manufacturing the cabling used in these power cable assemblies. Halogen is commonly used since it provides a flexible cable that is fire-resistant. Unfortunately, materials that are used for halogen-free cabling are themselves not fire retardant. Further, the addition of fire-retardant chemicals makes halogen-free cables brittle and is therefore not suitable. Accordingly, various embodiments of the present invention provide a strain relief that provides fire protection and is halogen-free. An example is shown in the following figure. 
       FIG. 5  illustrates portions of a strain relief  500  according to an embodiment of the present invention. Strain relief  500  includes interior portion  510  and exterior portion  520 . Cabling  516  passes through interior portion  510 . Interior portion  510  can be formed or molded of a single piece of material. This material may be a hard plastic, such as a polycarbonate, polycarbonate ABS blend, or other appropriate material. This may provide fire protection, protecting an electronic device that is being charged. 
     Outer portion  520  of strain relief  500  may be formed in an additional molding step. This type of molding may be referred to as a double-shot process. Cable  526  passes through exterior portion  520 . Exterior portion  520  may be formed around a projection or key  512  of interior portion  510 , to provide a secure fit between interior portion  510  and exterior portion  520 . Key  512  may have protrusions such that exterior portion  520  does not rotate relative to interior portion  510 . Exterior portion  520  may be made of a flexible material, such as a thermoplastic elastomer, fluorinated ethylene propylene, or other appropriate material. Exterior portion  520  may provide the flexibility needed to protect cable  526  from excessive wear at its interface with strain relief  500  and the housing. 
     Interior portion  520  may be located in a housing. This housing may enclose a power transformer or converter, wired or wireless data or communication circuitry, or other types of electronics circuitry. The color of exterior portion  520  may be made to match a color of the housing or cable. 
     In other embodiments of the present invention, strain relief  500  may be formed using a three step process. In these embodiments, the additional step is a first molding step where cables  526  and  516  are covered. The following two steps provide the remainder of interior portion  510  and exterior portion  520 . In various embodiments of the present invention, cables  526  and  516  may be one cable or they may be multiple cables. 
       FIG. 6  illustrates a strain relief  600  according to an embodiment of the present invention. Strain relief  600  includes interior portion  610  and exterior portion  620 . Interior portion  610  may provide fire protection, while exterior portion  620  may provide a flexible strain relief A side of a housing, shown here by dashed lines, may fit in the gap or slot  628 . Again, the housing may house transformers, data communications circuitry, and other types of electronic circuitry. 
     The above description of 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. Thus, it will be appreciated that the invention is intended to cover all modifications and equivalents within the scope of the following claims.

Metadata:
Filing Date: 20130917
Publication Date: 20160308
Grant Date: 20160308
Priority Date: 20091020
Inventors: GAO ZHENG
DIFONZO JOHN C.
BANKO JOSHUA
KIM MIN CHUL
Assignee: APPLE INC
CPC Classifications: [{"code": "H01R9/03", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/5845", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01R13/5816", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R2201/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/7175", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/24", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/6205", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B27/365", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/7175", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B2457/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/6205", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01B7/29", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B2250/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01B7/29", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R2201/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/6205", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/24", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/5816", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/24", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/5816", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R2201/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R2201/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R9/03", "inventive": true, "first": true, "tree": "[]"}, {"code": "B32B3/30", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B27/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/7175", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B3/266", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R9/03", "inventive": true, "first": false, "tree": "[]"}, {"code": "B32B2307/3065", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/24", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/5845", "inventive": true, "first": true, "tree": "[]"}, {"code": "B32B2250/24", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R13/6205", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/5816", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R13/7175", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R9/03", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01R13/5845", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R11/30", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 43334555