Locking mechanism for an enclosure

Information

  • Patent Grant
  • 6416090
  • Patent Number
    6,416,090
  • Date Filed
    Tuesday, August 31, 1999
    25 years ago
  • Date Issued
    Tuesday, July 9, 2002
    22 years ago
Abstract
A locking mechanism for an enclosure includes a top housing member and a bottom housing member having at least one latch portion. The top housing member includes at least one top housing deflecting tab portion for deflecting the latch portion. The bottom housing member includes at least one bottom housing retaining tab portion. The top housing deflecting tab portion is slidably engaged with the bottom housing retaining tab portion to secure the top housing member to the bottom housing member and to prevent movement of the top housing member relative to the bottom housing member.
Description




FIELD OF THE INVENTION




This invention relates generally to the field of protective enclosures, and in particular, to a locking mechanism for a modem enclosure.




BACKGROUND OF THE INVENTION




Enclosures for conventional modems typically include a first shell portion (typically a base portion) and a second shell portion (typically a cover portion) that is fastened to the first shell portion. The first and second shell portions are each typically comprised of plastic.




Attempts have been made to fasten the first and second shell portions together with a plurality of conventional fasteners such as, for example, screws or bolts. However, the number of conventional fasteners required for each modem enclosure greatly increases the bill of materials (BOM) costs. Moreover, fastening the first and second shell portions together with conventional fasteners is labor intensive and results in increased manufacturing costs.




In addition to the above, attempts have been made to provide a means to fasten the first and second shell portions together without the use of separate conventional fasteners. For example, attempts have been made to provide a latch mechanism to fasten the first and second shell portion together. Typically, either the first or second shell portion includes a plurality of cantilevered beam elements that are integrally formed with the shell portion and extend outward from the shell portion in a direction along the “Z” axis. The other shell portion includes a plurality of retaining members that are aligned with the beam elements. When the first and second shell portions are positioned together, the beam elements deflect in a direction along the “X” axis when they contact the retaining members. Once the beam elements pass the retaining members, they return to their undeflected state and are retained by the retaining members.




The disadvantage of conventional integrally formed latch mechanisms is that they oftentimes fail when the assembled enclosure is subject to certain forces during impact testing. This is due to the fact that they typically only provide a retaining force in one direction such as, for example, in a direction along the “Z” axis. Moreover, the latch mechanisms are typically the primary means holding the two shells of the enclosure together. As a result, if a force is applied to the outer shell in a direction along the “Z” axis, the latch mechanism may be susceptible to failure, which in turn may result in the separation of the two shells.




Also, difficulties arise in assembling enclosures with conventional latch mechanisms due to the insertion forces generated by the plurality of beam elements and the corresponding retaining members. The disassembly of the enclosure may be particularly difficult due to the high separation force that must be applied to the first and second shell portions to cause the plurality of beam elements to disengage from the plurality of retaining members. Finally, mechanical degradation of the beam elements and the retaining portions typically results when the enclosure is disassembled. As a result, the enclosure cannot be reassembled after it has been disassembled for the first time.




Accordingly, it would be desirable to have a locking mechanism for an enclosure that overcomes the disadvantages described above.




SUMMARY OF THE INVENTION




One aspect of the invention provides a locking mechanism for an enclosure including a top housing member and a bottom housing member. The bottom housing member includes at least one latch portion. The top housing member includes at least one top housing deflecting tab portion for deflecting the latch portion. The bottom housing member also includes at least one bottom housing retaining tab portion. The top housing deflecting tab portion is slidably engaged with the bottom housing retaining tab portion to secure the top housing member to the bottom housing member and to prevent movement of the top housing member relative to the bottom housing member.




Another aspect of the invention provides a locking mechanism for a modem enclosure including a top housing member and a bottom housing member. The bottom housing member includes at least one latch portion to prevent movement of the top housing member relative to the bottom housing member in a first direction. The top housing member includes at least one top housing deflecting tab portion for deflecting the latch portion. The bottom housing member further includes at least one bottom housing retaining tab portion. The top housing deflecting tab portion is slidably engaged with the bottom housing retaining tab portion in a second direction to secure the top housing member to the bottom housing member and to prevent movement of the top housing member relative to the bottom housing member in a third direction. The first direction may preferably be an arcuate path that allows the top housing member to disengage from the bottom housing member. The second direction may preferably be an arcuate path that allows the top housing member to engage with the bottom housing member. The second direction may preferably be opposite the first direction. The third direction may preferably be a vertical path that allows the top housing member to separate from the bottom housing member. The at least one top housing deflecting tab portion may comprise two top housing deflecting tab portions, and the at least one latch portion may comprise two latch portions. The at least one bottom housing retaining tab portion may comprise eight bottom housing retaining tab portions. The top housing member may further include at least one top housing retaining tab portion. The at least one top housing retaining tab portion may preferably be slidably engaged with the at least one bottom housing retaining tab portion. The at least one top housing retaining tab portion may comprise six top housing retaining tab portions. The at least one latch portion may preferably include an end portion having a rib portion. The bottom housing member may preferably include a perimeter portion, and the at least one latch portion and the at least one bottom housing retaining tab portion may each be positioned along the perimeter portion. Similarly, the top housing member may preferably include a perimeter portion, and the at least one top housing defecting tab portion may be positioned along the perimeter portion. The top and bottom housing members may each be formed from a single piece of insulative material. The insulative material may preferably be plastic.




Another aspect of the invention provides a method of operating a locking mechanism. A top housing member and a bottom housing member are provided. The bottom housing member includes at least one latch portion. The top housing member includes at least one top housing deflecting tab portion. The bottom housing member includes at least one bottom housing retaining tab portion. The top housing deflecting tab portion is slidably engaged with the bottom housing retaining tab portion. The latch portion is deflected by the at least one top housing deflecting tab portion. The top housing member is secured to the bottom housing member thereby preventing movement of the top housing member relative to the bottom housing member.




Another aspect of the invention provides a method of operating a locking mechanism for a modem enclosure. A top housing member and a bottom housing member are provided. The bottom housing member includes at least one latch portion. The top housing member includes at least one top housing deflecting tab portion. The bottom housing member includes at least one bottom housing retaining tab portion. The latch portion is deflected by the at least one top housing deflecting tab portion. The top housing deflecting tab portion is slidably engaged with the bottom housing retaining tab portion in a second direction. The top housing member is secured to the bottom housing member, and movement of the top housing member relative to the bottom housing member in a first direction is prevented. Movement of the top housing member relative to the bottom housing member in a third direction is also prevented. The first direction may preferably be an arcuate path that allows the top housing member to disengage from the bottom housing member. The second direction may preferably be an arcuate path that allows the top housing member to engage with the bottom housing member. The third direction may preferably be a vertical path that allows the top housing member to separate from the bottom housing member. The top housing member may preferably be positioned against the bottom housing member, and the top housing deflecting tab portion may preferably contact with the bottom housing retaining tab portion. The latch portion may preferably be deflected to allow movement of the top housing member relative to the bottom housing member in the first direction. The top housing member may preferably be disengaged from the bottom housing member.




The invention provides the foregoing and other features, and the advantages of the invention will become further apparent from the following detailed description of the presently preferred embodiments, read in conjunction with the accompanying drawings. The detailed description and drawings are merely illustrative of the invention and do not limit the scope of the invention, which is defined by the appended claims and equivalents thereof.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is an exploded perspective view of a preferred embodiment of a locking mechanism for an enclosure which is made in accordance with the invention;





FIG. 2

is an assembled view of the embodiment of

FIG. 1

;





FIG. 3

is a sectional view showing the top housing member exploded from the bottom member;





FIG. 4

a sectional view showing the top housing member positioned against the bottom housing member in the disengaged position;





FIG. 5

is the embodiment of

FIG. 4

showing the top housing deflecting tab portion slidably engaged with the bottom housing retaining tab portion and the latch portion in a deflected state; and





FIG. 6

is the embodiment of

FIG. 4

showing top housing member engaged with the bottom housing member.











DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS




Referring to

FIGS. 1-2

, a preferred embodiment of a locking mechanism for an enclosure


10


includes a top housing member


12


and a bottom housing member


14


. The enclosure


10


may preferably be any enclosure including, for example, an enclosure for an electronic device such as a modem. As shown in

FIGS. 1-2

, the top housing member


12


and the bottom housing member


14


may each be formed from a single piece of insulative material such as, for example, plastic. The plastic may preferably be flame retardant to meet UL requirements, and may consist of, for example, polycarbonate ABS plastic. In the embodiment shown, the bottom housing member


14


has a generally rectangular shape, although other shapes and configurations are contemplated. In the embodiment shown, the top housing member


12


also has a generally rectangular shape, and is adapted to mate with the bottom housing member


14


.




Referring to

FIGS. 1 and 3

,


5


, the bottom housing member


14


includes at least one latch portion


16


. As shown in

FIG. 6

, when the top housing member


12


is fully engaged with the bottom housing member


14


, the latch portion


16


prevents movement of the top housing member


12


relative to the bottom housing


14


in a first direction (FD). As shown in

FIG. 6

, the first direction (FD) may preferably be an arcuate path that allows the top housing member


12


to disengage from the bottom housing member


14


.




As shown in

FIG. 1

, the latch portion


16


is positioned along a perimeter portion


18


of the bottom housing member


14


. The latch portion


16


may preferably be integrally formed with the bottom housing member


14


. Alternatively, the latch portion


16


may be a separate member. As shown in FIGS.


1


and


3


-


6


, the latch portion


16


may preferably include an end portion


20


having a rib portion


22


. As shown in

FIG. 1

, the latch portion


16


may preferably be cantilevered from the perimeter portion


18


of the bottom housing member


14


so that it can be deflected when a force is applied to it. The latch portion


16


is positioned adjacent one side


24


of the bottom housing member


14


. An identically configured second latch portion


26


may preferably be positioned adjacent the opposite side


28


of the bottom housing member


14


.




Referring again to FIGS.


1


and


3


-


6


, the bottom housing member


14


also includes at least one bottom housing retaining tab portion


30


. The bottom housing retaining tab portion


30


may preferably extend outward from the perimeter portion


18


of the bottom housing member


14


and may preferably have an L-shaped configuration. However, alternative shapes and configurations of the bottom housing retaining tab portion


30


may be provided. The bottom housing retaining tab portion


30


may preferably be integrally formed with the bottom housing member


14


. Alternatively, the bottom housing retaining tab portion


30


may be a separate member.




In the embodiment shown in

FIG. 1

, a plurality of bottom housing retaining tab portions


30


,


32


,


34


,


36


,


38


,


40


,


42


,


44


are provided, four adjacent each of the sides


24


,


28


of the bottom housing member


14


. In the embodiment shown, the plurality of bottom housing retaining tab portions


30


,


32


,


34


,


36


,


38


,


40


,


42


,


44


have the same configuration. The number of bottom housing retaining tab portions


30


,


32


,


34


,


36


,


38


,


40


,


42


,


44


may vary depending upon the particular application. In the embodiment shown, the bottom housing retaining tab portions


30


,


32


,


34


,


36


,


38


,


40


,


42


,


44


are spaced along the perimeter portion


18


of the bottom housing member


14


.




Referring again to FIGS.


1


and


3


-


6


, the top housing member


12


includes at least one top housing deflecting tab portion


50


for deflecting the latch portion


16


. The top housing deflecting tab portion


50


is positioned along a perimeter portion


52


of the top housing member


12


. The top housing deflecting tab portion


52


may preferably extend outward from the perimeter portion


52


of the top housing member


12


and may preferably have an L-shaped configuration. The top housing deflecting tab portion


50


may preferably be integrally formed with the top housing member


12


. Alternatively, the top housing deflecting tab portion


50


may be a separate member. The top housing defecting tab portion


50


is oriented relative to the bottom housing retaining tab portion


30


to allow the top housing defecting tab portion


50


to be slidably engaged with the bottom housing retaining tab portion


30


in a second direction (SD) as shown in FIG.


5


. The second direction (SD) may preferably be an arcuate path that allows the top housing member


12


to engage with the bottom housing member


14


. The second direction (SD) may preferably be opposite the first direction (FD).




Slidably engaging the top deflecting tab portion


50


with the bottom housing retaining tab


30


portion secures the top housing member


12


to the bottom housing member


14


and prevents movement of the top housing member


12


relative to the bottom housing member


14


. In particular, slidably engaging the top deflecting tab portion


50


with the bottom housing retaining tab portion


30


prevents movement of the top housing member


12


relative to the bottom housing member


14


in a third direction (TD). As shown in

FIG. 3

, the third direction (TD) may preferably be a vertical path that allows the top housing member


12


to separate from the bottom housing member


14


.




In the embodiment shown in

FIG. 1

, a second top housing deflecting tab portion


54


for deflecting the second latch portion


26


is also provided. The second top housing deflecting tab portion


54


, which as shown in

FIG. 1

is configured the same as the top housing deflecting tab portion


50


, may preferably be positioned opposite the top housing deflecting tab portion


50


adjacent the perimeter portion


52


of the top housing member


12


. The top housing


12


member may further include at least one top housing retaining tab portion


56


. The top housing retaining tab portion


56


may preferably be slidably engaged with the at least one of the bottom housing tab portions, and in particular, bottom housing tab portion


44


. In the embodiment shown, six top housing retaining tab portions


56


,


58


,


60


,


62


,


64


,


66


are provided, three on each side of the top housing member


12


. The six top housing retaining members


56


,


58


,


60


,


62


,


64


,


66


slidably engage with six of the bottom housing retaining tabs


44


,


42


,


40


,


32


,


36


,


38


, respectively, to further secure the top housing member


12


to the bottom housing member


14


and prevent movement of the top housing member


12


relative to the bottom housing member


14


.




To assemble the enclosure


10


, the top housing member


12


is positioned against the bottom housing


14


member as shown in FIG.


4


. At this point, the latch portion


16


is in an undeflected state. The top housing deflecting tab portion


50


is slidably engaged with the bottom housing retaining tab portion


30


in the second direction (SD) as shown in FIG.


5


. As shown in

FIG. 5

, the latch portion


16


is deflected by the top housing deflecting tab portion


50


. As shown in

FIG. 6

, when the top housing deflecting tab portion


50


is in full contact with the bottom housing retaining tab portion


30


and passes over the end portion


20


of the latch portion


16


, the latch portion


16


returns to its undeflected state. When the top housing member


12


is fully engaged with the bottom housing member


14


as shown in

FIG. 6

, the latch portion


16


prevents movement of the top housing member


12


relative to the bottom housing member


14


in the first direction (FD). The top housing deflecting tab portion


50


and the bottom housing retaining tab portion


30


secure the top housing member


12


to the bottom housing member


14


and also prevent movement of the top housing member


12


relative to the bottom housing member


14


in the third direction (TD) (see FIG.


3


). The advantage of this arrangement is that the latch portion


16


is not relied upon to prevent movement of the top housing member


12


relative to the bottom housing member


14


in the third direction (TD). As a result, the latch portion


16


is not susceptible to failure when the enclosure


10


is subjected to forces exerted during impact testing. Moreover, the top housing member


12


and the bottom housing member


14


are less likely to separate from one another during impact testing due to the interlocking nature of the top housing deflecting tab portion


50


and the bottom housing retaining tab portion


30


. In particular, if a force is applied to the top housing member


12


, the top housing deflecting tab portion


50


is forced against the bottom housing retaining tab portion


30


thereby forcing the top housing member


12


and the bottom housing member


14


together.




To disassemble the enclosure, the latch portion


16


is deflected. The top housing member


12


is slidably moved relative to the bottom housing member


14


in the first direction (FD) (see FIG.


6


). When the top housing deflecting tab portion


50


is no longer in contact with the bottom housing retaining tab portion


30


, the top housing member


12


can be disengaged from the bottom housing member


14


.




One advantage of the present invention is that it eliminates the high insertion forces associated with conventional latching mechanisms. In particular, the force required to slide the top housing member


12


onto the bottom housing member


14


is relatively low because only two latch portions


16


,


26


have to be deflected. Similarly, the force required to dissemble the top housing member


12


from the bottom housing


14


member is also greatly reduced. Finally, the top housing member


12


and the bottom housing member


14


can be assembled and disassembled many times without mechanical degradation of the latch portions


16


,


26


.




While the embodiments of the invention disclosed herein are presently considered to be preferred, various changes and modifications can be made without departing from the spirit and scope of the invention. The scope of the invention is indicated in the appended claims, and all changes that come within the meaning and range of equivalents are intended to be embraced therein.



Claims
  • 1. A method of operating a locking mechanism for a modem enclosure comprising:providing a top housing member and a bottom housing member, the bottom housing member including at least one latch portion attached to a periphery thereof, the top housing member including at least one L-shaped top housing deflecting tab portion, the bottom housing member including at least one inverted L-shaped bottom housing retaining tab portion; deflecting the at least one latch portion with the at least one top housing deflecting tab portion; slidably engaging the at least one top housing deflecting tab portion with the at least one bottom housing retaining tab portion in a second direction; securing the top housing member to the bottom housing member; allowing the at least one latch portion to return to an undeflected condition; preventing movement of the top housing member relative to the bottom housing member in a first direction wherein the first direction is an arcuate path that allows the top housing member to disengage from the bottom housing member; and preventing movement of the top housing member relative to the bottom housing member in a direction normal to the first and second direction.
  • 2. The method of claim 1 wherein the second direction is an arcuate path that allows the top housing member to engage with the bottom housing member.
  • 3. The method of claim 1 wherein a third direction is a vertical path that allows the top housing member to separate from the bottom housing member.
  • 4. The method of claim 1 further comprising:positioning the top housing member against the bottom housing member.
  • 5. The method of claim 1 further comprising:contacting the at least one top housing deflecting tab portion with the at least one bottom housing retaining tab portion.
  • 6. The method of claim 1 further comprising:deflecting the at least one latch portion to allow movement of the top housing member relative to the bottom housing member in the first direction; and, disengaging the top housing member from the bottom housing member.
  • 7. A method of operating a locking mechanism comprising:providing a top housing member and a bottom housing member, the bottom housing member including at least one integrally formed deflectable latch portion, the top housing member including at least one integrally formed rigid L-shaped top housing deflecting tab portion, the bottom housing member further including at least one integrally formed rigid inverted L-shaped bottom housing retaining tab portion; deflecting the at least one integrally formed deflectable latch portion with the at least one integrally formed rigid top housing deflecting tab portion; slidably engaging the at least one integrally formed rigid top housing deflecting tab portion with the at least one integrally formed rigid bottom housing retaining tab portion; securing the top housing member to the bottom housing member; allowing the at least one integrally formed deflectable latch portion to return to an undeflected condition; and preventing movement of the top housing member relative to the bottom housing member.
US Referenced Citations (7)
Number Name Date Kind
4967902 Sobel Nov 1990 A
4993762 Rogers Feb 1991 A
5106143 Soeters Apr 1992 A
5398162 Bice Mar 1995 A
5402309 Ohgami Mar 1995 A
5548643 Dalgleish Aug 1996 A
6125668 Belden Oct 2000 A