Abstract:
A latch release is provided for engaging a latching mechanism of a connector. The latch release includes a housing cooperatively associated with the connector having a passageway that defines a first open end and a second open end. The second open end of the passageway is positioned adjacent to an operative portion of the latching mechanism. A rail is slidably positioned within the passageway and includes a front end that projects outwardly from the second open end of the passageway adjacent to the operative portion of the latching mechanism. A rear end of the rail projects outwardly from the first open end of the passageway so that when the rail is slid through the passageway, the front end of the rail engages the operative portion of the latching mechanism thereby releasing the connector. A method of unlatching a connector is also disclosed.

Description:
This application claims priority from a Provisional Patent Application entitled Latching Slide Rail, filed by the same inventors on Sep. 8, 1999, and accorded Ser. No. 60/152,807. 
    
    
     FIELD OF THE INVENTION 
     The present invention generally relates to electrical interconnection devices, and more particularly to mechanisms used to secure and release such devices to and from each other. 
     BACKGROUND OF THE INVENTION 
     Electrical connectors typically have a multiplicity of terminal contacts positioned in an insulating housing, and arranged so as to be connected to a complementary connector to form a connector pair. It is well known to use mechanical latching mechanisms for maintaining the connection between the two connectors. These mechanical latching mechanisms have been heretofore designed as either actuating slides or as one or more inter-engaging levers positioned on each connector of the pair. Examples of connectors utilizing such devices may be found in U.S. Pat. Nos.: 5,947,776, 5,785,540, 5,725,324, 5,399,109, 5,255,154, and 4,995,826. European Patent No. EP587174 A2 also discloses a slide mechanism that is consistent with the prior art. 
     In such prior art devices, the actuating slide is integrated in one of the connectors in either a guide groove or a guide slot, with the second connector of the pair having the complementary mating portion of the latching mechanism. Typically, when the connectors are mated, the actuating slide causes a lug or the like to move through the guide groove or the guide slot so as to secure the connector pair together. Very often the actuating slides are moved in a transverse direction with respect to the insertion direction of the connectors. This arrangement is not always satisfactory, especially when it is used in conjunction with multiple connectors that are positioned either side-by-side or stacked one above the other. 
     There is a need in the art for connectors that can be released from one another when the latching mechanism is located in a remote position, or in an arrangement with other connector pairs that provides little or no space for actuation. This need in the art has become acute in connection with many “high density” interconnection systems, where unlatching must take place under difficult circumstances, e.g., in a blind space where several such connectors are arranged in a stacked configuration. 
     SUMMARY OF THE INVENTION 
     The present invention provides a latch release for engaging an operative portion of a latching mechanism of a connector to switch the latching mechanism between a latched position and an unlatched position. In a preferred embodiment, the latch release includes a housing cooperatively associated with the connector and having a passageway therethrough that defines a first open end and a second open end. The second open end of the passageway is positioned adjacent to the operative portion of the latching mechanism. A rail is slidably positioned within the passageway and comprises a front end that projects outwardly from the second open end of the passageway adjacent to the operative portion of the latching mechanism. A rear end of the rail projects outwardly from the first open end of the passageway so that when the rail is slid through the passageway, the front end of the rail engages and actuates the operative portion of the latching mechanism. 
     A method of releasing a latched connector is also provided that comprises positioning a rail in slidable relation to a passageway defined through a portion of the connector so as to be engagable with an operative portion of a latching mechanism and sliding the rail into engagement with the operative portion of the latching mechanism so as to unlatch the connector. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features and advantages of the present invention will be more fully disclosed in, or rendered obvious by, the following detailed description of the preferred embodiment of the invention, which is to be considered together with the accompanying drawings wherein like numbers refer to like parts and further wherein: 
     FIG. 1 is a perspective view of an electrical connector having a slide rail latch formed according to the present invention; 
     FIG. 2 is a side elevational view of the connector shown in FIG. 1; 
     FIG. 3 is a cross-sectional view of the connector shown in FIG. 2; 
     FIG. 4 is a perspective view of a top shell portion of the connector shown in FIG. 1; 
     FIG. 5 is a cross-sectional view of the top shell shown in FIG. 4; 
     FIG. 6 is a perspective view of a slide rail formed in accordance with the present invention; 
     FIG. 7 is a cross-sectional view of the slide rail shown in FIG. 6; 
     FIG. 8 is a side elevational view of a plurality of electrical connectors, each having a slide rail latch formed according to the present invention and mated in a stacked configuration to corresponding connectors; and 
     FIG. 9 is a side elevational view of a plurality of electrical connectors, each having a slide rail latch formed according to the present invention and mated in a side-by-side configuration to corresponding connectors. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following description of the preferred embodiments of the invention are intended to be read in connection with the foregoing drawings and are to be considered a portion of the entire written description of this invention. As used in the following description, terms such as, “horizonal”, “vertical”, “up”, “down”, “top” and “bottom” as well as adjectival and adverbial derivatives thereof (e.g., “horizontally”, “downwardly”, “upwardly”, etc.) simply refer to the orientation of the structure of the invention as it is illustrated in the particular drawing figure when that figure faces the reader. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate. Also, the terms “connected” and “interconnected”, when used in this disclosure to describe the relationship between two or more structures, mean that such structures are secured or attached to each other either directly or indirectly through intervening structures, and include pivotal connections. The term “operatively connected” means that the foregoing direct or indirect connection between the structures allows such structures to operate as intended by virtue of such connection. 
     FIG. 1 shows an electrical connector  5  terminated to the end of a cable  7  and having a shield housing  9  formed according to the present invention. Electrical connector  5  may comprise any of the well known high density interconnection devices that are designed to meet the ANSI X3T11 standard, such as the HSSDC connectors marketed by AMP Inc., Berg Electronics, Inc., Amphenol Inc., or other HSSDC or similar high density electrical interconnection devices known in the art. Connectors of this type typically include a plurality of closely spaced, electrically conductive pin or receptacle contacts (not shown) arranged within an insulative housing  12 , and individually terminated at one end  13  to a corresponding plurality of conductors (not shown) that form the central portion of cable  7 . The electrical interconnection features of the plurality of closely spaced pin or receptacle contacts are positioned adjacent to an interface surface  14  of the connector. A cable strain relief  15  is often slipped over the outer portion of cable  7  to reduce the stress and strain placed on the individual wire terminations during handling and use of electrical connector  5 . 
     Housing  12  of electrical connector  5  is typically formed from one of the well known polymer materials that are suitable for injection molding, e.g., polyhalo-olefins, polyamides, polyolefins, polystyrenes, polyvinyls, polyacrylates, polymethacrylates, polyesters, polydienes, polyoxides, polyamides and polysulfides and their blends, co-polymers and substituted derivatives thereof. Housing  12  also normally includes a resilient latch  16  positioned on an outer surface, and arranged to releasably engage a corresponding feature on a mating electrical connector  18  that may be mounted on the edge of a printed wiring board  20 , as shown for example in FIGS. 8 and 9. Latch  16  may comprise various known shapes and include several alternative features that are adapted for releasably engaging a corresponding feature on a mating electrical connector  18 , e.g., recesses, notches, shoulders, catches, or tabs, etc. FIGS. 1 and 2 show a representative latch  16  that includes a recessed portion  24 , that is adapted to engage a corresponding protrusion or the like (not shown) on a mating connector  18 . 
     Typically, latch  16  will comprise a cantilevered beam that is fixed, via a living hinge  21  or the like, at a first end  22  that is adjacent to interface surface  14 . Latch  16  extends rearwardly from first end  22  toward cable  7 , and at an acute angle relative to the top surface of housing  12 . In this way, depressing latch  16  toward the top surface of housing  12  stores elastic energy in living hinge  21  so that when released, latch  16  springs away from the top surface of housing  12  and toward its original unloaded position. 
     Terminal end  26  of latch  16  often includes a raised feature that is adapted for aiding in depressing latch  16 , such as is generally represented by radiused portion  28 . Radiused portion  28  may take various known shapes so long as it is arranged so that a finger or tool may depress it to release latch  16  from engagement with mating connector  18 . For example, when connectors  5  and  18  are mated together, as shown in FIGS. 8 and 9, radiused portion  28  may be depressed, thus disengaging recessed portion  24  from a corresponding latching protrusion (not shown) on mating connector  18 . However, as is illustrated best in FIG. 8, due to the high density requirements placed on such connectors, little or no space (shown generally at reference numeral  30 ) is available for the insertion of a person&#39;s finger or tool to depress latch  16  and thereby release connector  5  from connector  18 , as intended by the design. This situation is often acute in applications that require a plurality of interconnection devices to be engaged to the same circuit board in a closely spaced architecture. 
     The present invention solves this problem in the art by providing a shield housing  9  comprising a top shell  45 , a bottom shell  50 , and a slide rail  55  that are advantageously arranged to aid in the actuation of latch  16 . More particularly, top shell  45  and bottom shell  50  each comprise a concavely shaped, complementary body portion having a pair of parallel spaced arms  59  that project outwardly from a front end  60  and a cable exit opening  62  defined at a rear end  64  (FIGS.  2 - 5 ). Body portions  57  of top shell  45  and bottom shell  50  may be formed from either a conductive material, e.g., brass, zinc, steel, conductive polymers, etc., or an electrically insulating material, e.g., any of the well-known polymer materials disclosed hereinabove in connection with housing  12 . The body portions are designed so as to mate along a peripheral edge  66  to form a partially enclosed void space or cavity that is sized and shaped to contain and cooperate with at least a portion of housing  12 , the terminated end of cable  7 , and a portion of cable strain relief  15  (FIG.  3 ). An annular stud  68  projects inwardly from the inner surface of the body portions, adjacent to rear end  64 , to engage a corresponding recess in cable strain relief  15  so as to hold cable strain relief  15  securely in place. 
     Referring to FIGS. 3 and 5, the body portion of top shell  45  further includes an outer wall  70  and an inner wall  72  that are spaced apart to define an open ended passageway  74 . Outer wall  70  includes a front edge  76  and a rear edge  78 . A recessed notch  86  is defined in the inner surface of outer wall  70 , adjacent to rear edge  78 . Inner wall  72  includes a front edge  82  and a rear edge  84 . Rear edge  84  is spaced away from the rear opening of passageway  74 , adjacent to cable exit opening  62  at rear end  64 , so as to provide a rail support surface  84 . Passageway  74  preferably comprises a substantially rectangular cross-sectional shape, having a somewhat larger cross-sectional size than slide rail  55 , and having openings at front edges  76 , 82  at front end  60 , and at rear edge  78  of outer wall  70 . 
     Referring to FIGS.  2 - 3  and  6 - 7 , slide rail  55  is slidably positioned within passageway  74 , and comprises an elongate, substantially flat beam having a front end  90 , a rear end  92 , and a catch  94 . More particularly, front end  90  includes a cam  96  that projects radially outwardly from a bottom surface of slide rail  55 . Cam  96  includes a chamfered front surface  98  that is shaped and sized for sliding engagement with an operative portion of latch  16 , e.g., radiused portion  28 , as will hereinafter be disclosed in further detail. Rear end  92  includes a tapered recess  100  that extends axially into slide rail  55 . Tapered recess  100  is sized so as to accept the working end of a tool, such as a conventional screw driver or knife blade tip. 
     Catch  94  comprises a cantilevered beam that is formed within a window  102  defined in a rear portion of slide rail  55 . Catch  94  is fixed at one end to an edge of window  102  by a living hinge  104  so that free end  106  is positioned above the edges of window  102 . In this way, when free end  106  is depressed downwardly, toward window  102 , elastic energy is stored in living hinge  104  which, in turn, tends to bias catch  94  outwardly, away from slide rail  55 . A recessed notch  110  is defined on the outer surface of catch  94 , adjacent to free end  106 . Slide rail  55  may be formed from any of the well-known polymer materials disclosed hereinabove in connection with housing  12  or from any other suitably rigid and resilient material, e.g., spring quality metals. 
     Referring to FIG. 8, when a pair of connectors  5 , 18  are mated in a stacked configuration, the space  30  available between each connector  5  is particularly narrow such that the radiused portion  28  of each latch  16  may not be easily accessed so as to release latch  16  from engagement with a corresponding latching mechanism on mating connector  18 . The present invention allows for the disengagement of latch  16  in the following manner. When connector  5  is in the position shown in FIG. 8, slide rail  55  is positioned within passageway  74  with chamfered surface  98  positioned adjacent to radiused portion  28 , but not depressing it. Rear end  92  of slide rail  55  is spaced away from rear edge  78  of outer wall  70 , and catch  94  is in an unbiased state with free end  106  positioned above window  102 . 
     To unlatch connector  5  from connector  18 , the tip portion of a tool, e.g., a screwdriver, knife blade, etc. (not shown) is positioned in tapered recess  100  of slide rail  55 . The tool is then pushed axially against slide rail  55 , causing slide rail  55  to slide longitudinally with respect to passageway  74 , and toward connector  18 . As this happens, chamfered surface  98  engages radiused portion  28  of latch  16  and depresses latch  16  toward the top surface of housing  12 . Slide rail  55  thus moves over latch  16 , depressing radiused portion  28 , and thereby releasing latch  16  from engagement with the corresponding latching mechanism on mating connector  18 . 
     At the same time that slide rail  55  is moving into engagement with radiused portion  28  of latch  16 , catch  94  moves toward rear edge  78  of outer wall  70 . As rear edge  78  engages catch  94 , catch  94  pivots about living hinge  104 , toward window  102 , and slides into passageway  74 . This pivoting movement of catch  94  biases catch  94  against outer wall  70 . Slide rail  55  and catch  94  slide into passageway  74  until recessed notch  110  of catch  94  engages recessed notch  86  of outer wall  70 . This engagement locks slide rail  55  in position such that cam  96  resides directly over top of radiused portion  28  of latch  16 , thereby holding latch  16  in a substantially fully depressed position so that connector  5  can be disengaged from connector  18  by, e.g., pulling on cable  7 . 
     Once connector  5  has been removed from engagement with connector  18 , slide rail  55  can be repositioned to its initial starting configuration by merely depressing free end  106  of catch  94  while at the same time pushing front end  90  of slide rail  55  rearwardly toward rear end  64  of the body portion so that catch  94  springs outwardly, via living hinge  104 , and away from window  102 . It will be understood that the present invention works equally well in a side-by-side connector configuration, as shown in FIG.  9 . 
     It is to be understood that the present invention is by no means limited only to the particular constructions herein disclosed and shown in the drawings, but also comprises any modifications or equivalents within the scope of the claims.