Abstract:
An electrical unit, such as a fire or gas detector, carries a three conductor plug for receipt of energy, AC hot, and neutral, as well as for coupling to a bidirectional signaling line. A multiple conductor adapter makes it possible to couple the plug to a plurality of incompatible, previously installed sockets. The adapter can be fully contained in a single housing. Alternately, it can include a housing for some of the conductors with the remainder carried on a cable which extends from the housing.

Description:
FIELD OF THE INVENTION 
     The invention pertains to AC-powered ambient condition detectors. More particularly, the invention pertains to connectors and adapters for coupling such detectors to existing AC sockets. 
     BACKGROUND OF THE INVENTION 
     Fire detectors which can be battery powered or powered with utility supplied AC current are known. Battery powered detectors have become very popular as they are self-contained and can easily be installed almost anywhere. They are usually stand alone devices which do not interact with other similar detectors in the same region or installation. 
     Detectors which are coupled together by a communications line provide an alternate to stand alone, battery powered units. Such systems usually incorporate a three conductor cable. Two conductors (AC hot and neutral) provide electrical energy to power the detectors. A third conductor is used for signaling between detectors. 
     The cables terminate in three conductor sockets. A matching plug couples each detector to the cable. 
     Over a period of time, different socket/plug combinations have been used by manufacturers. In fact, there have been instances where a later model detector would not be compatible with previously installed sockets of the same manufacturer. 
     The problem of older, previously installed sockets impedes the replacement of older detectors with more current models. Where AC powered, or, interconnected detectors are installed in residences or small businesses, there may not be persons available who can safely remove the existing sockets and replace them with sockets compatible with more current models from the same or different manufacturers. 
     There is an on-going need to facilitate replacement of older AC powered, or, interconnected detectors with more current models. It would be most desirable if current detectors could be coupled to existing sockets without requiring any rewiring. 
     SUMMARY OF THE INVENTION 
     A connection adapter which facilitates coupling electrical units, such as fire or gas detectors, heat detectors or the like, to electrical cables includes a nonconductive housing. The housing carries a first set of electrical conductors and a second set of electrical conductors. The number of conductors is the same for both sets. 
     The first set exhibits an electromechanical plug profile for engagement with socket elements of an existing connector. The second set exhibits an electromechanical socket profile for engagement with a second plug carried by a respective electrical unit. 
     In a disclosed embodiment, the electrical units are fire or gas detectors which are to receive electrical energy, from a remote source, via a respective electrical plug. One form of electrical energy is utility supplied AC. 
     The adapter interfaces between the electrical plug of the respective detector and an existing power distribution cable which has an existing socket with a profile that is unlike the plug. Where the cable carries AC, for example, the adapter converts the configuration of the existing AC socket to that of the plug which exhibits two contacts, AC hot and neutral for example. 
     In one form, the adapter has a single two sided housing. One side is a plug for mating with the existing AC connector at the cable. The other side is a socket for mating with the detector&#39;s plug. 
     In another embodiment, the adapter has a socket for engagement with the detector&#39;s plug. A plurality of conductors extends from the adapter. The conductors engage individual contacts of the socket carried by the cable to couple electrical energy form the cable to the respective detectors. 
     In yet another embodiment, the installed socket includes a third, signaling conductor. The adapter mates with the installed three conductor socket and with a three conductor plug carried by the electrical unit. 
     Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram of a system illustrating a problem solved by the present invention; 
     FIG. 2 is a schematic diagram illustrating exemplary wiring of a type found in systems as in FIG. 1; 
     FIG. 3 is a diagram of one embodiment of the present invention; 
     FIG. 3A is an enlarged fragmentary view of a portion of FIG. 3; 
     FIGS. 4A, B, taken together illustrate another embodiment of the invention; 
     FIG. 4C is a composite view of the embodiment of the invention of FIGS. 4A, B; 
     FIG. 5 illustrates yet another embodiment of the invention; 
     FIG. 5A is an enlarged view of a portion of FIG. 5; 
     FIG. 6A is one view of an adapter which embodies the present invention; 
     FIG. 6A-1 is another view of the adapter of FIG. 6A; 
     FIG. 6B illustrates yet another adapter which embodies the present invention; 
     FIG. 6B-1 illustrates another view of the adapter of FIG. 6B; 
     FIG. 6C is a view of yet another adapter which embodies the present invention; and 
     FIG. 6C-1 is another view of the adapter in FIG.  6 C. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     While this invention is susceptible of embodiment in many different forms, there are shown in the drawing and will be described herein in detail specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated. 
     FIG. 1 illustrates a system  10  of ambient condition detectors  12   a,b,c, . . . n.  These detectors are all coupled to a multiple conductor cable, such as a two conductor AC utility line  14 . The cable  14  can also include a third conductor for inter-detector signaling purposes as would be known to those of skill in the art. 
     Each of the detectors, such as  12   a , has a plurality of internal conductors  12   a - 1  (indicated in phantom) which extends therefrom and which is terminated by a plug  12   a - 2  of a predetermined configuration. Each of the plugs  12   a - 2  . . .  12   n - 2  is compatible with and is intended to engage a corresponding socket, such as the sockets  14   a,b,c,d . . . n  carried on and coupled to the cable  14 . 
     In known installations, sockets  14   a,b,c,d . . . . n  mate with corresponding plugs  12   a - 2  . . . .  12   n - 2  to couple power to the respective detector and to provide intra-detector signaling. Such configurations provide convenience in installation and safety by isolating the power contacts from direct access by installer or maintenance personnel. 
     The above described system  10  is limited in that a replacement detector  16  which has a plug  16 - 2  with a different configuration can not be installed to replace detector  12   a  without altering or replacing socket  14   a . This exposes the AC power lines and requires skill to be carried out safely. 
     FIG. 2 illustrates socket  14   a  with three conductors  14   a - 1 ,- 2 ,- 3  coupled by wire nuts to multi-conductor cable  14 . Changing socket  14   a  so as to be compatible with plug  16 - 2  requires removing the respective wire nuts and installing a socket compatible with plug  16 - 2 . 
     FIG. 3 illustrates an adapter  30  which can be used to couple plug  16 - 2  to socket  14   a  safely and without any need to alter or replace the existing sockets  12   a,b,c,d . . . n.  The adapter  30  includes a socket  32  which is compatible with plug  16 - 2 . A plurality of conductors  34  extends from socket  32 . FIG. 3A is an enlargement of a portion of FIG.  3  and illustrates of adapter  30 . 
     Each of the conductors  34   a,b,c  has a free end which carries an insulator, such as  34   a - 1 . Each insulator covers a respective pin  34   a - 2  which is compatible with a respective socket-element in a socket such as socket  14   a . The conductors  34   a,b,c  of adapter  30  are inserted into socket elements in socket  14   a . Those pins thus engage the respective socket elements safely and conveniently. The plug  16 - 2  of replacement detector  16  can be coupled to adapter socket  32  so as to receive power and signals off of cable  14 . 
     FIG. 4A illustrates an alternate adapter system  40 . Adapter system  40  has a socket  42  which is compatible with plug  16 - 2 . Conductors  44  extend from socket  42 . A positioning, or locating element, such as  44   a - 1  is carried adjacent a free end of each conductor. Each conductor carries at the free end a respective pin, such as pin  44   a - 2 . 
     FIG. 4B illustrates a configurable shell, or housing  46 . Housing  46  includes a holder  46   a  and a spacer  46   b . Positioning elements  44   a - 1 , b - 1 , c - 1  can be inserted into and locked in holder  46   a , along with spacer  46   b  with an arrangement which is compatible with a respective socket such as socket  14   a  as illustrated in FIG.  4 C. The pins  44   a - 2 ,  b - 2  and  c - 2  extend from holder  46   a  forming a plug  48 . 
     The plug  48  is compatible with socket  14   a  while the socket  42  is compatible with plug  16 - 2 . The detector  16  can now be safely and conveniently coupled to cable  14 . 
     The adapter  40  can readily be configured by a home owner or other installer prior to any engagement with the respective socket such as socket  14   a . Adapter  40  can be used with a variety of different sockets merely by rearranging the location of spacer  46   b  and the relative positions of the pins  44   a - 23 ,  b - 2  and  c - 2 . 
     FIG. 5 illustrates an adapter system  50  which incorporates a socket  52  which is compatible with plug  16 - 2 . Conductors  54  extend from socket  52 . FIG. 5A is an enlarged view of a portion of the adapter  50 . 
     A housing  56  carries a plurality of spacing elements such as the elements  54   a - 1 ,  b - 1  and  c - 1  from which extend plug pins  54   a - 2 ,  b - 2 , and  c - 2  (comparable to the positioning elements  44   a - 1 ,  b - 1 , and  c - 1  and pins  44   a - 2 ,  b - 2  and  c - 2 , best seen in FIG. 4A.) In the system  50 , the housing  56  exhibits five locations into which the spacing elements  54   a - 1 ,  b - 1  and  c - 1  can be moved for purposes of configuring the pins  54   a - 2 ,  b - 2  and  c - 2  in a way which is compatible with a respective previously installed socket such as one of the sockets  14   a, b, . . . n.    
     By rearranging the connector pins  54   a - 2 ,  b - 2  and  c - 2 , a user or installer can readily configure the adapter system  50  for connection with one or more preexisting sockets. The configuration process takes place off-line with no connection to the existing sockets or cable  14  thus providing for a user&#39;s convenience and safety. 
     FIGS. 6A, B and C each illustrate a different integrally formed adapter in accordance with the present invention. FIGS. 6A-1,  6 B- 1  and  6 C- 1  each illustrate a different view of the respective adapter of FIGS. 6A,  6 B and  6 C. 
     In FIG. 6A, an adapter  60  has a housing  62  with first and second ends  62   a, b . The end  62   a  carries a plug  62 - 1  configured to mate with an existing socket, such as socket  14   n  of cable  14 . End  62   b  carries a socket  62 - 2  configured to mate with plug  16 - 2 . 
     Using adapter  60 , new detectors can be installed in existing systems quickly and safely. An adapter, such as adapter  60 , is especially convenient, as no discrete wires need to be inserted. All wiring between each plug  62 - 1 , end  62   a  is coupled to an appropriate plug  62 - 2 , end  62   b  by conductors internal to housing  62 . Coupling between respective socket  62 - 2  and plug  62 - 1  can be implemented using discrete conductors or printed wiring. Adapter  60  need only be plugged into socket  14   a  and to plug  16 - 2  to install detector  16 . 
     FIGS. 6B and 6C illustrate alternate forms of adapters  70  and  80 . Each carries a plug on a respective end  72   a ,  82   a  whose elements are connected to a socket carried on a respective end  72   b ,  82   b . Socket elements are connected to respective plug elements within a respective housing  72 ,  82 . 
     Other configurations are possible as adapters  60 ,  70  and  80  are exemplary only. All such configurations come within the spirit and scope of the present invention. One such variation is to combine movable pins or plug elements, as in FIG. 5 in the integrally formed configurations of FIG. 6A, B or C. Hence, one adapter  60  can be used with a variety of pre-existing socket configurations. 
     From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims.