Patent Publication Number: US-6671160-B2

Title: ESD prevention device enabled latch

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates generally to latching devices and more particularly to an electrostatic discharge prevention device enabled latch. 
     2. Background 
     In electronic assemblies and systems, where user access is desirable or field repair may be required, there exists a possibility of inducing damage to electronic circuits through electrostatic discharge (ESD). Best practices for minimizing damage due to ESD are known, but observance of those practices in the field may be difficult or impossible. As a result, damage may occur to circuitry which may result in adverse effects on system operation where access is gained to a circuit or assembly without employing ESD practices or procedures. 
     It would, therefore, be advantageous to provide for proper ESD handling of electronic assemblies and systems, modules and circuits by providing an electrostatic discharge prevention device enabled latch to be incorporated in the design of electronic assemblies and modules where access or entry to an electronic device is controlled by a latched access, panel, door or the like. Additionally, it may be desirable to incorporate an ESD ground strap as a portion of the electrostatic discharge prevention device enabled latch. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to an electrostatic discharge prevention device enabled latch. The electrostatic discharge prevention device enabled latch may be employed on or with an enclosure including an access panel attached to the enclosure. The enclosure with the access panel closed forms a Faraday cage protecting the contents from ESD. Opening the access panel exposes the contents to ESD. The electrostatic discharge prevention device enabled latch includes a latch for retaining an access panel in a closed position. The latch may be disengaged by operation of a latch release member which functions to effect release or disengagement of the latch. A conductor receptacle is attached to the enclosure, typically in the proximity of the access panel and is in electrical contact with the enclosure which is in turn typically conductively connected to the enclosure contents through some finite resistance. An electrostatic discharge prevention device, including a ground strap or static dissipative mat and a conductive terminal, are provided for use by an individual desiring to gain access through the access panel to service enclosed components or circuits. When the conductive terminal is inserted into the conductor receptacle, a latch release member is displaced disengaging the latch. 
     The conductive terminal and the conductor receptacle may be configured as any cooperating conductive terminal and receptacle combination. In one preferred embodiment of the invention, the conductive terminal and the conductor receptacle are configured as a standard “banana” jack. 
     The latch release member may be configured as a sliding bolt which reciprocatingly contacts the latch and mechanically effects disengagement of the latch. The sliding bolt protrudes into the conductor receptacle and is displaced by the insertion of the conductive terminal. The latch is spring biased towards an engaged position for retaining the access panel in a closed position until released by operation of the conductive terminal against the sliding bolt. Alternately, the latching mechanism may be configured as a latch retainer switch, which electrically switches a latch operator such as a solenoid or motor to effect operation of the latch in response to the position of the latch retainer switch. The latch retainer switch protrudes into the conductor receptacle and is displaced by the insertion of the conductive terminal. In this case, when the latch retainer switch is displaces and closes the switch circuit, a latch operator is signaled and activated to disengage the latch allowing access to the enclosure. When the conductive terminal is withdraw, the latch retainer switch returns to a biased open position and the latch may be engaged. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective representational view of an enclosure including an electrostatic discharge prevention device enabled latch according to the present invention; 
     FIG. 2 is a perspective representational view of an electrostatic discharge prevention device enabled latch according to the present invention; 
     FIG. 3 is a perspective representational view of an electrostatic discharge prevention device enabled latch according to the present invention; 
     FIG. 4 is a representational side cutaway view of an enclosure including an electrostatic discharge prevention device enabled latch according to the present invention; and 
     FIG. 5 is a representational side cutaway view of an enclosure including an electrostatic discharge prevention device enabled latch according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIGS. 1 through 5, electrostatic discharge prevention device enabled latch  10  will be more fully described. FIG. 1 shows electronic assembly  11  including enclosure  12 . Enclosure  12  includes access panel  13 . Electrostatic discharge prevention device enabled latch  10  provides controlled access to enclosure  12 . 
     Referring to FIGS. 2 and 3, enclosure  12  is shown including access panel  13  shown in a closed position in FIG.  2  and in an open position in FIG.  3 . Electrostatic discharge prevention device enabled latch  10  includes electrostatic discharge prevention device  20  having conductor  21 , conductively connecting ground strap  22  to terminal  23 . Terminal  23  includes conductor  25  which is insertable into conductor receptacle  24  as shown in FIG.  2 . As shown in FIG. 3, when conductor  25  is inserted into conductor receptacle  24  access panel  13  will open making accessible electronic package  15 . 
     Referring to FIGS. 4 and 5 enclosure  12  is shown including access panel  13  pivotable in relationship to housing  17  of enclosure  12  at hinge  14 . Access panel  13  is shown in a closed position in FIG.  4  and in an open position in FIG.  5 . Access panel  13  is biased towards an open position by spring  16 . Conductor  25  of terminal  23  is shown insertable into conductor receptacle  24  as shown in FIG.  4 . Conductor receptacle  24  is conductively attached to housing  17  of enclosure  12  by conductor  27 . As shown in FIG. 5, when conductor  25  of terminal  23  is inserted into conductor receptacle  24  access panel  13  will open making accessible, electronic package  15 . 
     FIGS. 4 and 5 show latch  30  which reciprocates in connection with bolt  31 . As conductor  25  of terminal  23  is inserted into conductor receptacle  24 , conductor  25  of terminal  23  displaces bolt  31  which in turn acts against latch  30 , moving latch  30  to a disengaged position, wherein lip  32  of latch  30  is pushed inside of the edge of housing  17 . Latch  30  is biased in towards an engaged position by spring  33  as shown in FIG.  4 . Bolt  31  in this case is passive and reciprocates in relationship with the biased latch  30  and the insertion or removal of conductor  25 . 
     While this invention has been described with reference to the detailed embodiments, this is not meant to be construed in a limiting sense. Various modifications to the described embodiments, as well as additional embodiments of the invention, will be apparent to persons skilled in the art upon reference to this description. It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the true scope of the invention.