Latch apparatus

Information

  • Patent Grant
  • 6527309
  • Patent Number
    6,527,309
  • Date Filed
    Wednesday, September 19, 2001
    23 years ago
  • Date Issued
    Tuesday, March 4, 2003
    21 years ago
Abstract
A latch apparatus includes a release mechanism having a depending locking arm for selectively arresting the release mechanism in a locking position. The release mechanism further includes a center of gravity and an axis of rotation about which the release mechanism pivots between a release position and the locking position. The center of gravity of the release mechanism is located along the axis of rotation.
Description




FIELD OF THE INVENTION




This invention relates in general to a latch apparatus, and deals more particularly with a latch apparatus having a release button which is configured to resist unintentional disengagement from its arresting position.




BACKGROUND OF THE INVENTION




Latches are utilized in many diverse fields, most commonly in container manufacturing and the like, where it is necessary to selectively secure a lid to a container body during shipping or other transportation. Although differing in specific size, shape and operation, most latch designs include an integrated release mechanism which may be selectively operated to disengage the release mechanism from its arresting position.




One known configuration of a release mechanism is a release button which is functionally integrated with the latch body. When actuated by an operator, the release button will typically rotate about an axis to disengage a locking ridge of the release button from its arresting boss, thus causing the latch as a whole to open. It is obviously a primary design parameter of latches that they reliably open when desired, while staying shut at all other times. Unfortunately, this operational characteristic may be compromised in certain situations.




As mentioned previously, the use of latches are widespread in the container field and, as such, typically experience a myriad of stresses, including fluctuations in ambient temperature and pressure, as well as having to endure the forces generated during handling. In particular, latched containers are frequently subjected to sudden and jolting drops which impart damage not only to the container body, but also affect the operation of the latch itself.




By way of example, when a container is dropped or otherwise experiences a sharp blow, a torque may be imparted on the rotational release mechanism of the latch apparatus. The torque may in fact be so great that the release mechanism involuntarily rotates out of engagement with the container's arresting boss causing the container to suddenly open, sometimes with disastrous results.





FIG. 1

depicts a cross-sectional view of a release mechanism


10


which may be subject to the detrimental torque forces noted above. As shown in

FIG. 1

, the release mechanism


10


includes a locking ridge


12


which selectively mates with an unillustrated arresting boss of a container. The release mechanism


10


further includes an integrated rod


14


which enables the release mechanism


10


to rotate about a rotational axis R when pressure is applied to a release button


16


, thereby disengaging the locking ridge


12


from the container's arresting boss. It will be readily appreciated that an unillustrated biasing spring, or the like, is utilized to normally bias the locking ridge


12


into contact with the container's arresting boss.




As depicted in

FIG. 1

, the release mechanism


10


has a center of gravity which is disposed on an axis CG, the center of gravity axis CG being offset from the rotational axis R by a predetermined amount O. As will be appreciated, by having the center of gravity of the release mechanism


10


offset from the rotational axis R, the weight of the release mechanism


10


will cause a torque to be generated when the container to which the release mechanism


10


is connected is dropped. This generated torque may thereby overcome the otherwise sufficient force of the biasing spring and precipitate the disengagement of the locking ridge


12


from the container's arresting boss, as discussed previously. The greater the offset O, the greater the torque that the release mechanism


10


may experience upon being dropped.




Structural modification of the release mechanism may be accomplished in order to attempt to limit the incidence of catastrophic failure of the latch apparatus itself, such as by increasing the biasing force which keeps the release mechanism in its closed position. Although arguably effective, such a modification would not be desirable as increasing the biasing force of the release mechanism, that is, increasing the size of the unillustrated biasing spring in

FIG. 1

, would inherently increase the force required to selectively rotate the release mechanism open, thus making any latch apparatus so modified more difficult to intentionally operate. Moreover, the manufacture of larger constituent parts of the latch apparatus is more costly and adds to the weight and volume of the latch apparatus and container as a whole.




It is thusly apparent that existing latch apparatuses may suffer from the unintentional disengagement between their release mechanism and the arresting boss of the container when the container is dropped or otherwise jarred.




With the forgoing problems and concerns in mind, it is the general object of the present invention to provide a latch apparatus which overcomes the above-described concerns and drawbacks, without compromising economic viability and operational effectiveness.




SUMMARY OF THE INVENTION




It is an object of the present invention to provide a latch apparatus for a container.




It is another object of the present invention to provide a latch apparatus for a container which is configured to resist unintentional disengagement from its arresting position.




It is another object of the present invention to provide a latch apparatus for a container that includes a rotatable release mechanism.




It is another object of the present invention to provide a latch apparatus for a container that includes a rotatable release mechanism which substantially inhibits the generation of torque to the release mechanism when the container is dropped.




It is another object of the present invention to provide a latch apparatus for a container which includes a release mechanism having a center of gravity located on the rotational axis of the release mechanism.




According to one embodiment of the present invention a latch apparatus includes a release mechanism having a depending locking arm for selectively arresting the release mechanism in a locking position. The release mechanism further includes a center of gravity and an axis of rotation about which the release mechanism pivots between a release position and the locking position. The center of gravity of the release mechanism is located along the axis of rotation.




These and other objectives of the present invention, and their preferred embodiments, shall become clear by consideration of the specification, claims and drawings taken as a whole.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a cross-sectional view of a known rotational release mechanism of a latch apparatus.





FIG. 2

is a perspective view of a container incorporating a latch apparatus according to one embodiment of the present invention.





FIG. 3

is a perspective view of the underside of the latch apparatus shown in FIG.


2


and the arresting boss disposed on the container.





FIG. 4

is a plan view of the top side of the latch apparatus, according to one embodiment of the present invention.





FIG. 5

is a plan view of the underside of the latch apparatus, according to one embodiment of the present invention.





FIG. 6

is a partially exploded, perspective view of the latch apparatus, according to one embodiment of the present invention.





FIG. 7

is a cross-sectional view of a rotational release mechanism of the latch apparatus, according to one embodiment of the present invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT





FIG. 2

is a perspective view of a container


100


which incorporates a latch apparatus


102


according to one embodiment of the present invention. As illustrated in

FIG. 2

, the container


100


includes a first half


104


and a second half


106


which are releasably mated to one another via the operation of the latch apparatus


102


. It will be readily appreciated that the container


100


is shown for illustrative purposes only, and that the latch apparatus


102


of the present invention may be employed on containers having a wide range of structural configurations, without departing from the broader aspects of the present invention.




Operation of the latch apparatus


102


is effectuated primarily through the selective depression of a release button


108


defined on the top side, or exterior surface, of the latch apparatus


102


.

FIG. 3

illustrates an arresting boss


110


formed on the container


100


which, when the latch apparatus


102


is rotated downwardly towards a locking position, serves to momentarily pivot a locking arm


112


of the release button


108


over the arresting boss


110


to subsequently lock thereon.





FIG. 4

more clearly illustrates the exterior surface of the latch apparatus


102


. As shown in

FIG. 4

, the latch apparatus


102


defines a housing having a rectangular opening


114


in its exterior surface for supporting the substantially flush-mounted release button


108


therein. A finger depression


116


, or the like, may be formed on the planar actuation area


117


of the release button


108


to assist in securely locating an operator's finger thereon for subsequent operation of the release button


108


. As will be appreciated, the latch apparatus


102


will rotate between an open and a closed position about a latch rotational axis L. The latch apparatus


102


may be secured to the container


100


via a rod or the like which is oriented along the rotational axis L and rotationally integrated with the body of the container


100


.





FIG. 5

more clearly illustrates the underside of the latch apparatus


102


. As shown in

FIG. 5

, the latch button


108


rotates about a rotational axis R and is urged towards a locking position under the biasing force of a spring


118


. The spring


118


, which may be a torsion spring or the like, is mounted upon a metallic or other resilient or semi-resilient bar


120


which itself is anchored to the housing of the latch apparatus


102


. A stop


122


may be formed or integrally molded on the latch apparatus


102


for limiting the rotational movement of the release button


108


as the release button


108


is pressed during operation. As is further depicted in

FIG. 5

, the spring


118


includes first and second distal ends,


119


and


121


respectively, which are correspondingly urged against the release button


108


and the housing of the latch apparatus


102


. A cavity


123


may be formed in the housing of the latch apparatus


102


for accommodating the second distal end


121


of the spring


118


in order to securely locate the spring


118


during repeated operation. It will, however, be readily appreciated that the cavity


123


may be alternatively formed in the release button


108


, or in both the housing and the release button


108


, without departing from the broader aspects of the present invention.




Turning now to

FIG. 6

, a partially exploded view of the latch apparatus


100


is depicted. As was discussed previously, it is a important aspect of the present invention to effectively inhibit the inadvertent and momentary pivoting of the release button


108


about its rotational axis R when the release button is subjected to drop-induced torquing forces and the like. The present invention accomplishes this goal by forming the release button


108


so that the center of gravity of the release button


108


lies along the rotational axis R of the bar


120


.




That is, as shown in

FIG. 6

, the bar


120


includes a pair of distal ends


125


which will extend through a matching pair of apertures


124


formed in the release button


108


. The distal ends


125


are themselves anchored within corresponding apertures


126


formed in the housing of the latch apparatus


102


. With the distal ends


130


of the spring


118


being disposed against the cantilevered section


132


of the release button


108


and the lip portion


136


of the latch apparatus, respectively, the release button


108


is capable of selectively pivoting from a locking position to a release position, as discussed previously.




In accordance with a primary aspect of the present invention, the apertures


124


of the release button


108


are formed to ensure that the center of gravity for the release button


108


lies along the rotational axis R, preferably mid-way between the apertures


124


, thus eliminating the offset O discussed in association with FIG.


1


.





FIG. 7

is a partial, cross-sectional side view of the release button


108


which shows the relationship between the rotational axis R of the bar


120


and the center of gravity CG of the release button


108


. A comparison of the release mechanism


10


of FIG.


1


and the release button


108


of

FIG. 7

illustrates the lack of any offset O between the rotational axis R and the center of gravity CG of the release button


108


, in accordance with a primary aspect of the present invention.




As previously mentioned, the inadvertent pivoting of the release button


108


due to torquing forces could also be addressed by increasing the size and rigidity of the spring


118


to such an extent that the release button


108


would not pivot under a predetermined set of design parameters and applied forces. Such a solution, however, is not desirable as one of ordinary skill in the art will appreciate that oversizing the spring


118


may lead to operational problems with the release button


108


when a pivoting action of the release button


108


is, in fact, desired by an operator. Moreover, the size, weight and manufacturing cost of the release button


108


would be correspondingly increased should a larger biasing spring be employed.




It will be readily appreciated that the present invention effectively eliminates the inadvertent pivoting of the release button


108


when the release button


108


experiences torquing forces as a result of the container


100


be dropped or otherwise jarred. The present invention accomplishes this goal by designing the release button


108


such that the mass of the release button


108


is substantially evenly distributed in a direction substantially perpendicular to the axis of rotation R of the release button


108


. That is, the present invention ensures that there is no unequal, cantilevered weight with respect to the center of gravity CG, at least in a direction substantially perpendicular to the rotational axis R of the release button


108


, which may precipitate a torque about the rotational axis R during times of applied force. Moreover, by aligning the center of gravity CG of the release button


108


with the rotational axis R of the release button


108


, the present invention advantageously avoids increasing the size, weight and manufacturing costs of the latch apparatus


102


as a whole.




It will also be readily appreciated that the latch apparatus


102


and the release button


108


of the present invention may be formed as a single, integrally molded device, or alternatively, be comprised of a plurality of separately molded or formed elements capable of functional integration with one another, without departing from the broader aspects of the present invention. Moreover, the latch apparatus


102


and the release button


108


of the present invention are preferably formed from a plastic or polymer material, however alternative resilient, metallic and non-metallic materials are also contemplated by the present invention.




While the present invention has been described in conjunction with

FIGS. 1-7

, the specific structural configuration of the constituent elements of the latch apparatus


102


are not limited to those configurations as disclosed herein. In particular, the release button


108


need not be rectangular in shape, nor be integrated in the latch apparatus


102


in a predetermined manner, provided that the center of gravity of the release button lies substantially along the rotational axis of the release button, the greatest benefit resulting from aligning the center of gravity precisely along the rotational axis.




While the invention had been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various obvious changes may be made, and equivalents may be substituted for elements thereof, without departing from the essential scope of the present invention. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention includes all embodiments falling within the scope of the appended claims.



Claims
  • 1. A latch apparatus, comprising:a release mechanism including a depending locking arm for selectively arresting said release mechanism in a locking position; an axis of rotation of said release mechanism about which said release mechanism pivots between a release position and said locking position; a bar which is concentrically aligned with said rotational axis, said bar being integrally mated with said release mechanism and includes a pair of distal ends which are disposed in a matching pair of apertures formed in said release mechanism; a housing which defines an opening in the exterior surface thereof, said release apparatus being mounted within said opening, wherein said distal ends of said bar extend through said matching pair of apertures and into receptacles formed in said housing; and a center of gravity of said release mechanism, wherein said center of gravity is located along said axis of rotation.
  • 2. The latch apparatus according to claim 1, further comprising:a biasing element for biasing said release mechanism into said locking position.
  • 3. The latch apparatus according to claim 2, wherein:said biasing element comprises a spring oriented about said bar.
  • 4. The latch apparatus according to claim 1, further comprising:said release mechanism includes a planar actuation area which is substantially flush with said exterior surface; and said planar actuation surface defines a depression thereon.
  • 5. A latch apparatus, comprising:a release mechanism pivotable about a bar between a locking position and a release position, said bar being coaxially aligned with a rotational axis of said release mechanism; a center of gravity of said release mechanism and a housing which rotatably supports said release mechanism; a torsion spring for biasing said release mechanism into said locking position; a stop member integrally formed with said housing, said stop member being oriented below a planar actuation area of said release mechanism for limiting a pivoting action of said release mechanism; said planar actuation area being mounted in an opening defined in an exterior surface of said housing; a finger depression formed in said planar actuation area, said planar actuation are being substantially flush mounted with said exterior surface of said housing; and wherein said bar extends through said center of gravity.
  • 6. The latch apparatus according to claim 5, further comprising:a depending locking arm integrally formed with said release mechanism for selectively arresting said latch apparatus in said locking position.
  • 7. The latch apparatus according to claim 5, wherein:said bar extends through said torsion spring.
  • 8. The latch apparatus according to claim 7, wherein:said torsion spring includes a first distal end and a second distal end; and said first distal end is urged against said release mechanism and said second distal end is urged against said housing.
  • 9. The latch apparatus according to claim 8, further comprising:a cavity formed in said housing for removably receiving said second distal end of said torsion spring.
  • 10. The latch apparatus according to claim 5, wherein:said housing and said release mechanism are comprised of injection molded plastic; and said bar is a metallic bar.
  • 11. A latch apparatus, comprising:a release mechanism including a depending locking arm for selectively arresting said release mechanism in a locking position; an axis of rotation of said release mechanism about which said release mechanism pivots between a release position and said locking position; a bar which is concentrically aligned with said rotational axis, said bar being integrally mated with said release mechanism and includes a pair of distal ends which are disposed in a matching pair of apertures formed in said release mechanism; a housing which defines an opening in the exterior surface thereof, said release mechanism being mounted within said opening; said release mechanism further including a planar actuation area, defining a depression thereon, which is substantially flush with said exterior surface; and a center of gravity of said release mechanism, wherein said center of gravity is located along said axis of rotation.
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