Abstract:
An integrated relay system includes an automotive relay and a terminal interface. The automotive relay includes switching contacts and a casing. The casing at least partially surrounds the switching contacts and includes an aperture. The terminal interface is electrically connected with at least one of the switching contacts and is configured to receive a portion of a fuse. The terminal interface also passes through aperture and extends away from the casing.

Description:
BACKGROUND 
       [0001]    1. Field 
         [0002]    Embodiments of the invention relate to automotive relay systems. 
         [0003]    2. Discussion 
         [0004]    A relay is an electrical switch that opens and closes under the control of another electrical circuit. In some relays, if a current flows through a coil, the resulting magnetic field attracts an armature that is mechanically linked to a moving contact. This movement may either connect or disconnect a connection with a fixed contact. If the current to the coil is switched off, the armature is returned by a force to its relaxed position. A spring or gravity may supply this force. 
         [0005]    If the coil is to be energized with direct current, a resistor may be electrically connected across the coil. Upon deactivation, this resistor may dissipate energy—which may otherwise generate a voltage spike—from the collapsing magnetic field. Some automotive relays having a casing may include this resistor inside the casing. Alternatively, a capacitor and resistor in series may be configured to absorb/dissipate this energy. 
         [0006]    If the coil is to be energized with alternating current, a copper ring may be crimped to an end of a solenoid. This ring may create an out-of-phase current that increases the minimum pull on the armature during the alternating current cycle. 
         [0007]    Certain relays are designed to operate quickly. This may reduce noise in low voltage applications and reduce arcing in high voltage or high current applications. 
         [0008]      FIG. 1  is a schematic view, in cross-section, of a prior art automotive printed circuit board relay  10 . The relay  10  includes a switch/contacts  12  and a coil  14  disposed within a housing  16 . An electrical potential applied to the coil  14  creates an electromagnetic field that actuates the switch  12 . 
         [0009]    The switch/contacts  12  includes electrical connector pins  18 ,  20  that protrude through the housing  16 . The coil  14  includes electrical connector pins  22 ,  24  that also protrude through the housing  16 . The connector pins  18 ,  20 ,  22 ,  24  may be attached to a printed circuit board (not shown). 
         [0010]      FIGS. 2A and 2B  are side and plan views respectively of a prior art printed circuit board assembly  26 . The assembly  26  includes a printed circuit board  28 , the relay  10 , forked terminals  30 ,  32  and a fuse  34 . The relay  10  is attached, e.g., soldered, to the printed circuit board  28 . The forked terminals  30 ,  32  are positioned next to the relay  10  and are also attached to the printed circuit board  28 . The forked terminal  30  is electrically connected with the connector pin  18 . The forked terminal  32  may be electrically connected with a power source (not shown). 
         [0011]    Blades  35  of the fuse  34  are retained by prong portions  36 ,  38  of the forked terminals  30 ,  32  respectively. The fuse  34  protects the relay  10  and any downstream components from spikes in electrical current. 
       SUMMARY 
       [0012]    An integrated relay system includes an automotive relay and a terminal interface. The automotive relay includes switching contacts and a casing. The casing at least partially surrounds the switching contacts and has a surface defining an aperture. The terminal interface is electrically connected with at least one of the switching contacts and is configured to receive a portion of a fuse. The terminal interface extends through the aperture and away from the casing. 
         [0013]    The terminal interface may comprise a female terminal. 
         [0014]    The female terminal may include a pronged portion to retain the portion of the fuse and a shoulder portion adjacent to the casing to support the pronged portion. 
         [0015]    A printed circuit board assembly includes a printed circuit board and a plurality of integrated relay systems attached with the printed circuit board. Each of the plurality of integrated relay systems includes an automotive relay and at least one terminal interface. The automotive relay includes (i) switching contacts electrically connected with the first printed circuit board and (ii) a casing at least partially surrounding the switching contacts. The casing has a surface defining an aperture. The at least one terminal interface is electrically connected with at least one of the switching contacts and is configured to receive a fuse. The at least one terminal interface passes through the aperture and extends away from the casing. 
         [0016]    The assembly may further include a plurality of fuses. Each of the fuses may be electrically connected with at least one of the terminal interfaces. 
         [0017]    A printed circuit board assembly includes first and second printed circuit boards, a fuse and an integrated relay system. The integrated relay system includes an automotive relay having (i) switching contacts electrically connected with the first printed circuit board and (ii) a casing at least partially surrounding the switching contacts and having a surface defining an aperture. The integrated relay system also includes a first terminal interface electrically connected with at least one of the switching contacts and configured to receive a portion of the fuse. The first terminal interface extends through the aperture and away from the casing. The second printed circuit board includes a surface defining an opening configured to receive the first terminal interface. The first terminal interface extends though the opening. The assembly also includes a second terminal interface attached to the second printed circuit board and configured to receive another portion of the fuse. The fuse is connected with the first and second terminal interfaces. 
         [0018]    The assembly may further include an electrical bus bar electrically connected with at least one of the terminal interfaces. 
         [0019]    While example embodiments in accordance with the invention are illustrated and disclosed, such disclosure should not be construed to limit the invention. It is anticipated that various modifications and alternative designs may be made without departing from the scope of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]      FIG. 1  is a schematic view, in cross-section, of a prior art automotive printed circuit board relay; 
           [0021]      FIG. 2A  is a side view of a prior art printed circuit board assembly; 
           [0022]      FIG. 2B  is a plan view of the prior art printed circuit board assembly of  FIG. 2A ; 
           [0023]      FIG. 3  is a schematic view, in cross-section, of an embodiment of an integrated relay system; 
           [0024]      FIGS. 4A and 4B  are schematic diagrams of portions of alternative embodiments of integrated relay systems; 
           [0025]      FIG. 5  is a perspective view of an embodiment of an automotive printed circuit board assembly; and 
           [0026]      FIG. 6  is a exploded assembly view of another embodiment of an automotive printed circuit board assembly. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    Referring now to  FIG. 3 , an embodiment of an integrated relay system  50  may include a switch/contacts  52  and a coil  54  disposed within a housing  56 . An electrical potential applied to the coil  54  creates an electromagnetic field that actuates the switch/contacts  52 . The system  50  may also include an interface terminal  58 , e.g., a forked terminal, box terminal or any other female (or male) terminal. As known to those of ordinary skill, a forked terminal is a female terminal configured to receive a blade of a fuse. The interface terminal  58  is electrically connected with the switch/contacts  52  and protrudes through an opening  60  in the housing  56 . As explained below, the interface terminal  58  is configured to receive and/or retain a fuse (not shown) of any suitable configuration. 
         [0028]    The switch/contacts  52  include electrical connector pins  62 ,  64  that protrude through the housing  56 . The coil  54  includes electrical connector pins  66 ,  68  that also protrude through the housing  56 . The connector pins  62 ,  64 ,  66 ,  68  may be attached, e.g., soldered, etc., to a printed circuit board (not shown). 
         [0029]    In the embodiment of  FIG. 3 , the interface terminal  58  extends normally away from a surface of the housing  56  opposite the connector pins  62 ,  64 ,  66 ,  68 . The interface terminal  58 , however, may protrude through and/or extend away from any suitable surface of the housing  56 . In other embodiments, additional interface terminals  58  may be electrically connected with the switch/contacts  52  and pass through the opening  60  or additional openings (not shown) in the housing  56 . In such embodiments, the interface terminals  58  may be located on a same side or different sides of the housing  56 . 
         [0030]    Referring now to  FIG. 4A , numbered elements that differ by 100 relative to the numbered elements of  FIG. 1  have similar, although not necessarily identical, descriptions to the numbered elements of  FIG. 1 . An embodiment of an integrated relay system  150  includes a switch/contacts  152 , coil  154  and terminal interface  158 . The coil  154  is electrically connected with the switch/contacts  152  and terminal interface  158 . 
         [0031]    Referring now to  FIG. 4B , numbered elements that differ by 200 relative to the numbered elements of  FIG. 1  have similar, although not necessarily identical, descriptions to the numbered elements of  FIG. 1 . An embodiment of an integrated relay system  250  includes switches/contacts  252 ,  253 , a coil  254  and terminal interface  258 . The switch/contacts  253  is normally closed. The coil  254  is not electrically connected with the switches/contacts  252 ,  253 . Of course, other electrical configurations are also possible. 
         [0032]    Referring now to  FIG. 5 , numbered elements that differ by 300 relative to the numbered elements of  FIG. 1  have similar, although not necessarily identical, descriptions to the numbered elements of  FIG. 1 . An embodiment of an automotive printed circuit board assembly  370  may include a printed circuit board  372  and a plurality of integrated relay systems  350  aligned in a row(s). In other embodiments, the relay systems  350 , however, may be positioned on the printed circuit board  372  as desired. 
         [0033]    In the embodiment of  FIG. 5 , the housings  356  of the relay systems  350  have a two-piece configuration. During manufacture of the relay systems  350 , the two-piece housings  356  are snapped together to encase a switch/contacts and coil (not shown). A seam  357  on each of the housings  356  results. Any suitable housing configuration, however, may be used. 
         [0034]    Each of the relay systems  350  are electrically connected with the printed circuit board  372  via connector pins  362 ,  364 ,  366 ,  368 . 
         [0035]    In the embodiment of  FIG. 5 , an electrical bus bar  378  rests on the housings  356  and may be electrically connected with an electrical source and/or sink (not shown), etc. In other embodiments, the electrical bus bar  378  may be routed above (and spaced away from) the housings  356 . Support members (not shown), for example, attached with and extending away from the printed circuit board  372  may be used to locate/hold/etc. the electrical bus bar  378  in such configurations. In still other embodiments, the housings  356  may include a feature (not shown), e.g., a trough, valley, etc., configured to locate/retain the electrical bus bar  378  on the housings  356 . In such embodiments, the electrical bus bar  378  may include complimentary features that further locate/retain the electrical bus bar  378  on the housings  356 . Other suitable arrangements are, of course, also possible. 
         [0036]    The electrical bus bar  378  includes terminal interface portions  379 . Each of the terminal interface portions  379  includes prong portions  380 . As explained below, the prong portions  380  may retain, for example, a blade of a fuse. 
         [0037]    The electrical bus bar  378  of  FIG. 5  is stamped from a single piece of metal. In other embodiments, however, the terminal interface portions  379  may be formed separately and attached, e.g., welded, to form the electrical bus bar  378 . Other configurations are also possible. 
         [0038]    For each of the relay systems  350 , a fuse  374  having blade portions  375  may be electrically connected with the interface terminal  358  and the electrical bus bar  378 . Of course, other suitably configured fuses  374  may be used. In the embodiment of  FIG. 5 , the blade portions  375  are retained by prong portions  376  of the terminal interface  358  and prong portions  380  of the terminal interface portion  379 . Other configurations, however, are also possible. 
         [0039]    As apparent to those of ordinary skill, each of the relay systems  350  occupies less area of the printed circuit board  372  relative to, for example, the relay  10  and forked terminals  30 ,  32  illustrated in  FIG. 2  because the interface terminals  358  are integral to the relay systems  350 . 
         [0040]    Referring now to  FIG. 6 , numbered elements that differ by 100 relative to the numbered elements of  FIG. 5  have similar, although not necessarily identical, descriptions to the numbered elements of  FIG. 5 . Another embodiment of an automotive printed circuit board assembly  470  may include a pair of printed circuit boards  472 ,  473 , an integrated relay system  450  electrically connected with the printed circuit board  472  and a terminal interface  459  electrically connected with the printed circuit board  473 . Of course, additional relay systems  450  and terminal interfaces  459  may be included and positioned as desired. 
         [0041]    The printed circuit board  473  includes a surface that defines an opening  482  configured to receive, as explained below, a terminal interface  458  of the relay system  450 . 
         [0042]    The terminal interfaces  458 ,  459  include respective prong portions  476 ,  461  each configured to receive and retain a blade portion  475  of a fuse  474 . The terminal interface  458  further includes shoulder portions  484  that flare out from a bottom of the prong portions  476 . In the embodiment of  FIG. 6 , the shoulder portions  484  contact the housing  456  and may reduce, for example, stresses on the terminal interface  458  when the blade portion  475  is inserted into or removed from the terminal interface  458 . In other embodiments, the shoulder portions  484  may, for example, be formed on and extend away from surface  485  of the terminal interface  458 . Other configurations are also possible. 
         [0043]    During assembly of the printed circuit board assembly  470  of  FIG. 6 , the prong portions  476  of the terminal interface  458  are inserted through the opening  482  so that the terminal interface  458  is adjacent to the terminal interface  459 . The housing  456  is thus sandwiched between the printed circuit boards  472 ,  473 . The blade portions  475  of the fuse  474  are then inserted into the prong portions  461 ,  476  to electrically connect the terminal interfaces  458 ,  459 . In embodiments having multiple relay systems  450  and terminal interfaces  459 , an electrical bus bar (not shown), such as the electrical bus bar  378  illustrated in  FIG. 5 , may be used to electrically connect the terminal interfaces  458  associated with some or all of the relay systems  450 . 
         [0044]    As apparent to one of ordinary skill, the configuration described with reference to  FIG. 6  may reduce the number of pins that run between the printed circuit boards  472 ,  473  and the number and size of associated circuit board traces relative to conventional stacked printed circuit board configurations. 
         [0045]    While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.