Patent Publication Number: US-7914316-B2

Title: Lock attachment for audio-visual connector

Description:
This is a regular application claiming the benefit under 35 U.S.C. 119(e) of U.S. Provisional App. No. 61/275,417 filed Aug. 28, 2009 for “Lock Attachment for Audio-Visual Connector”. 
    
    
     BACKGROUND 
     With the advent of HD TV, the HDMI (High-Definition Multimedia Interface) connector is now in common use as a compact audio/video interface for transmitting uncompressed digital data. This connector is having increased use as a means of digital interconnection between consumer electronics products such as digital audio/video (AV) sources to compatible system components such as digital audio devices, computer monitors, and digital televisions. 
     Conventional HDMI connectors ( FIG. 1 ) lack an effective locking feature to hold the connector plug into a socket. As a result of this deficiency, plugs can easily slip out of sockets. 
     This is a significant problem in the custom home theater, audio, video and residential electronic systems installation industry. The cables are heavy and the lack of effective locking features robust enough to keep the standard plug in place may result in a plug becoming dislodged from its socket. Disconnection of the HDMI interface is a very common occurrence and results in total loss of video and audio. Most HDMI connectors are of the conventional type, and the problem of disconnect is prevalent in both the currently installed and future user base. 
     Recently, a number of HDMI equipment manufacturers have added a threaded screw receptacle R above the HDMI socket, as shown in  FIG. 2 . With the addition of this threaded receptacle feature, specialty HDMI cables that feature connectors with an integrated locking screw mechanism S may be used to secure the plug to the socket (see  FIG. 3 ). 
     SUMMARY 
     In one aspect, the present invention is directed to a clip that slips over a standard HDMI connector, and imparts a locking feature that is functionally similar to the locked plug shown in  FIG. 3 . 
     In another aspect, the invention is directed to the combination of a locking clip attached to a standard connector of the type shown in  FIG. 1 , thereby providing a functionality similar to the plug with integrated lock as shown in  FIG. 3 . 
     In a broader aspect the invention is directed to a locking clip for any type of electronic connector, comprising an elongated base having a through bore, a substantially tubular sleeve having sidewalls extending downwardly from the base and defining a hollow space having a longitudinal axis, and a clamp cantilevered from the base and including a substantially tubular collar substantially coaxially aligned with the tubular sleeve. A locking screw is insertable in the through bore, having a threaded front end and a shoulder spaced rearward and adapted to engage and push on the base. 
     Preferably, the through bore includes a socket at the front end, a mounting screw having a nut portion insertable in the socket and a threaded front end extending in front of the base, whereby the front end of the locking screw engages the nut of the mounting screw when the shoulder of the locking screw engages the base. 
     In another broad aspect, the invention is directed to the combination of an electronic connector plug and an attached locking clip, wherein the connector comprises a cable, a plug housing surrounding one end of the cable, and a plug supported in the housing, such that the plug extends from the front of the housing and is electrically connected through the housing to the cable. The clip surrounds the housing and can be locked onto an electrical component by a lock screw such that the advancing screw also urges a clamp against the housing thereby securing the plug into the jack of the component. The electrical component is preferably an audio-visual (AV) device having an HDMI socket. 
     Preferably, the back end of the housing forms a thrust shoulder with the cable and the locking clip at least partially surrounds the housing. The clip includes a base with a through bore offset from and parallel with the extension of the plug. The base has a back end that defines another thrust shoulder. A clamp extends rearward beyond the back of the housing and has a clamp shoulder confronting the thrust shoulder of the housing. The locking screw is insertable in the through bore, having a threaded front end and a screw shoulder spaced rearward of and adapted to engage and push on the thrust surface of the base when the locking screw is advanced directly or indirectly into a threaded receiving bore in an AV component facing the front of the housing, thereby also positioning or urging the clamp shoulder at or against the thrust shoulder of the housing. 
     The clamp is preferably a circular but open collar that snaps over the cable and rests against or bears on the back of the connector housing, preventing unintentional disconnection of the connector once the locking screw is connected to the AV component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is an oblique end view of a conventional HDMI cable and connector plug; 
         FIG. 2  is a view of a conventional HDMI jack on an AV component, with an optional adjacent threaded bore for receiving and locking an HDMI plug with integrated locking boss and screw; 
         FIG. 3  is a view similar to  FIG. 2 , showing an HDMI plug with integrated locking boss, secured to the HDMI jack; 
         FIG. 4  is an oblique side view of a clip embodiment of the present invention, for use with a conventional HDMI cable and plug such as shown in  FIG. 1 ; 
         FIG. 5  is a side view of the clip of  FIG. 5 , with the mounting and locking screws withdrawn for clarity; 
         FIG. 6  is a longitudinal section view similar to  FIG. 5 , with the locking screw in the clip; 
         FIG. 7  is longitudinal section view of the assembled cable, plug, and clip; and 
         FIG. 8  is a bottom view of the assembled cable, plug, and clip according to  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 4-6  show an embodiment of a locking clip assembly, having the basic elements of a clip  12  comprising an elongated base  14 , a substantially tubular sleeve having sidewalls  16   a ,  16   b  extending downwardly from the base and defining a hollow space  18  having a longitudinal axis, and a clamp  20  extending from the base and including a substantially tubular collar  22  substantially coaxially aligned with the tubular sleeve. In the intended usage, the base  14  will be at the top, with the two half-sleeves  16   a ,  16   b  having sufficient flexibility radially of the axis, to permit the sleeve to deformably slip over and then return to engage the housing of the AV connector, which will be further described below. Likewise, the clamp, in this case the collar  22 , is similarly a substantial cylinder except for an open slot at the bottom, which permits the collar to be slid over the cable with or without deformation. 
     Preferably, the clamp  20  is cantilevered, as by a downwardly inclined web  24 , from the base  14 , but exact coaxial alignment between the sleeve  16  and the collar  22  is not necessary at all times when the clip is attached to the cable and connector, because some accommodation can be afforded by the inherent flexibility of the web  24 . 
     In use, a thumbscrew  26  extends into a through bore  28  of the base, whereby the threaded tip of the thumbscrew directly or indirectly engages a threaded receptacle above the HDMI socket in the AV component (as shown in  FIG. 2 ). Although a single thumbscrew  26  can be used for this purpose, it is preferred that a separate mounting screw  30  be threaded into the receptacle on the AV component, and that the thumbscrew  26  be advanced into the mounting screw  30 . The base  14  has a back side which presents an external shoulder  32  around the through bore  28  and an internal shoulder  34  in the through bore. At the front of the base  14 , a socket  36  has an internal profile adapted to receive the external profile  38  of the mounting screw  30 . The externally threaded screw portion  40  of the mounting screw  30  can be threaded into the receptacle on the AV component, whereas the threaded front or nose portion  42  of the thumbscrew can be threaded into the internal threads of the nut portion  38 . The thumbscrew typically has a first shank portion  44  extending rearward from the threaded nose  42 , a first shoulder  46  associated with a second shank portion  48 , and a second shoulder  50  at the front of the enlarged thumb knob  52 . Preferably, the back end of the thumbscrew includes a slot  54  by which a tool can further tighten or loosen the thumbscrew. The thumbscrew is similar to conventional thumbscrews used with AV equipment. 
     Preferably, the relationships of the dimensions are such that when the thumbscrew  26  is advanced within the through bore  28 , the shoulder  50  bears against the thrust surface provided by external shoulder  32  after the nose  42  has been advanced well into the nut  38 , but before hitting a limit position within the nut. 
     With further reference to  FIG. 6  in particular, it may be seen that the through bore  28  has a relatively larger diameter portion  56  immediately adjacent the socket  36 , and an adjacent, relatively smaller diameter portion  58 , thereby forming an internal shoulder. In this manner, the thumbscrew  26  can be pulled back with the threads  42  withdrawn into the larger diameter bore portion  56  while stopped at the shoulder with bore portion  58  during the initial engagement of the connector and clip with the AV component socket and the nut portion  38  of the installed mounting screw  30 , respectively. 
       FIG. 7  is a cross-section view of the combination of clip assembly and connector assembly. The connector assembly comprises a cable  60 , a plug housing or shell  62  surrounding one end of the cable, and a plug  64  supported in the housing such that the plug extends from the front of the housing and is electrically connected, such as via conductor  66 , through the housing to a conductor in the cable. The back end  68  of the housing forms a shoulder relative to the diameter of the cable  60 . The base  14  of the clip  12  has a rearwardly extending clamp including collar  22  which surrounds at least some of the cable  60  and has an internal shoulder  70  which abuts the shoulder  68  at the back of the housing. 
     As previously described, with the mounting screw  30  already installed in the AV component and the thumbscrew  26  withdrawn so that the threads  42  are in the region  56  of the bore (see  FIG. 6 ), the assembly as shown in  FIG. 7  is advanced into the socket of the AV component such that the plug portion  64  is fully within the socket and the nut portion  38  of the mounting screw  30  is captured within the profile of the recess  36  at the front of the clip. The thumbscrew is then advanced such that the threads  42  engage the internal threads of the nut  38  and eventually cause the shoulder  50  on the thumbscrew to bear against the thrust surface  32  of the base  14  which in turn urges the collar  22  against another thrust surface provided by the shoulder  70 . This secures the entire assembly into the AV component. 
       FIG. 8  illustrates the condition shown in  FIG. 7  where the half-sleeves surround the housing and the collar surrounds the cable around at least about 180° span, such that the collar is positioned to engage or provide a stop surface at the back shoulder of the housing. 
     It should be appreciated that although the invention has been described with respect to HDMI plug connectors, the inventive concept is applicable to all types of AV connectors.