Patent Description:
Carpenters and handy persons often need to carry multiple containers/stackable bodies to a jobsite. These containers/stackable bodies are often latched to one another. Typical latches are manual connectors that include a swinging portion having a hook on a first body and a protruding portion suitable for engaging the hook on the second body. These manual connectors require an operator to actively move the swinging portion into engagement with the protruding portion. This manual movement may not always be convenient. It would be good to have a stacking latch mechanism that automatically secures two bodies together by simply placing one body on top of another. Such a stacking latch mechanism would secure the two bodies together without an operator needing to physically move any parts of the latch.

The prior art is replete with examples of stackable container assemblies. One such example can be found in <CIT>, which discloses a container assembly having a base unit and a removable container unit. <CIT> discloses an automatic latch and toolbox. Another example can be found in <CIT>, which discloses a drawer latch and toolbox assembly. <CIT> discloses a suitcase for the transport of tools.

The present invention overcomes one or more of the drawbacks discussed above.

The present invention relates to a latch mechanism configured to secure two bodies together by simply placing one body on top of the other and applying moderate downward pressure to the top body. Alternatively, the weight of the upper body would supply enough downward force to engage the latch mechanism and secure the two bodies together. The latch mechanism includes a housing and a latch partially disposed within the housing. The latch includes a main body, and a primary hook and an opposing secondary hook both extending from the main body. The latch is configured to be rotatable between a first position and a second position. In the first position, the primary hook is not obscured by the housing. In the second position, the primary hook is substantially obscured by the housing. The latch mechanism also includes a bias configured to bias the latch toward its first position.

In another embodiment, the housing of the latch mechanism may also be a lid of a container.

In yet another embodiment, the housing of the latch mechanism may also be a stackable body. In this embodiment, the housing may also include a step configured to be received by another latch mechanism.

An embodiment of the invention will now be described by way of example with reference to the drawings in which:.

<FIG> discloses an embodiment of a latch mechanism <NUM>. Latch mechanism <NUM> includes a housing <NUM> and a latch <NUM>. Latch <NUM>, which may be partially disposed within the housing <NUM>, includes a main body <NUM>, a primary hook <NUM> and an opposing secondary hook <NUM>. Latch <NUM> is rotatable within housing <NUM> between a first position and a second position. In the first position, the primary hook <NUM> is not obscured by the housing <NUM>. In the second position, the primary hook is substantially obscured by the housing <NUM>.

Latch mechanism <NUM> may also include one or more biases or springs <NUM>. Bias <NUM>, which is configured to bias the latch <NUM> toward its first position, may be disposed between an interior wall <NUM> of housing <NUM> and latch <NUM>.

The primary hook <NUM> extends away from the main body <NUM> and includes a step receiving surface <NUM>. Applying force to the step receiving surface <NUM> moves the latch <NUM> toward its second position. In a preferred embodiment, step receiving surface <NUM> may be angled. Primary hook <NUM> may further include a cantilevered surface <NUM>. A primary tooth <NUM> may be positioned on the cantilevered surface <NUM> so as to extend downwardly and partially across the width of step receiving surface <NUM>. Primary tooth <NUM> may be configured to engage a step <NUM> of a stackable body.

The secondary hook <NUM>, which also extends from main body <NUM>, may include a protruding arm <NUM>. A secondary tooth <NUM> is positioned at the end of the protruding arm <NUM>. Secondary tooth <NUM> extends upwardly from protruding arm <NUM> and has a length which is less than the length of primary tooth <NUM>. Secondary tooth <NUM> is configured to engage a step <NUM> of a stackable body.

The main body <NUM> of latch <NUM> may also include an operator surface <NUM>. The operator surface <NUM> is configured such that applying pressure thereto rotates the latch toward its second position. In a preferred embodiment, the operator surface <NUM> is positioned on the side of the main body <NUM> that is opposite the side from which the primary hook <NUM> and opposing secondary hook <NUM> extend.

Rotational movement of the latch <NUM> within housing <NUM> may be achieved by a pin <NUM> simultaneously disposed in a circular through opening <NUM> defined in the housing <NUM> and an opening <NUM> defined in the latch <NUM>. Those skilled in the art will recognize that the rotational movement can be improved with the use of multiple pins <NUM> and multiple openings <NUM>, <NUM>. As best seen in <FIG> and <FIG>, opening <NUM> may be defined in pin arms <NUM> that extend from the main body <NUM> of latch <NUM>. In a preferred embodiment, pin arms <NUM> extend from the same side of the main body <NUM> as do primary hook <NUM> and secondary hook <NUM>. As best seen in <FIG>, when latch <NUM> is positioned within housing <NUM>; pin <NUM>, circular through opening <NUM> and opening <NUM> are all on the same axis X. One pin <NUM> extends through one housing opening <NUM> and corresponding latch opening <NUM>. The laterally inward opening of through opening <NUM> includes a narrowed region against which pin <NUM> abuts. Alternatively, pins <NUM> may include channel regions and the inner ends of openings <NUM> may be formed with an inwardly extending collar region which may be forced into the channel regions to retain pins <NUM>. In either case, the opposite lateral ends of pins <NUM> extend laterally outwardly of housing <NUM>, and pins <NUM> have sufficient flexibility for slight lateral movement.

Latch <NUM> may also include one or depressions <NUM>. Depressions, <NUM> are sized and configured to receive a bias or spring <NUM>. When bias <NUM> is positioned within depression <NUM> and the interior wall <NUM> of housing <NUM>, the entire latch <NUM> is biased toward its first position. In a preferred embodiment, there may be two depressions <NUM> and they may be positioned on the main body <NUM> on the same side as the operator surface <NUM>.

The latch mechanism <NUM> of the present invention may have a variety of different embodiments. <FIG> show a first embodiment wherein the housing <NUM> is relatively compact. In this embodiment, the latch mechanism <NUM> may be used in conjunction with a container <NUM> such as that depicted in <FIG> and <FIG>. Container <NUM> may include a body <NUM> and a lid <NUM>. Body <NUM> includes a step <NUM> that is configured to be selectively engaged and disengaged to a latch mechanism <NUM>. Lid <NUM> contains one or more carveouts <NUM> that are configured to receive a latch mechanism <NUM> according to the first embodiment. As best seen in <FIG>, carveout <NUM> may include one or more slots <NUM> and holes <NUM>. In particular, slots <NUM> are formed in each side wall of carveout <NUM> near the laterally outermost edges thereof and extend downwardly from the top. Holes <NUM> are formed at the base of slots <NUM> and are formed as either regions of deeper indentations than the remainder of slots <NUM>, or extend entirely through lid <NUM>. Slots <NUM> and holes <NUM> are configured to receive pins <NUM>. More specifically, slots <NUM> function as guides as latch mechanism <NUM> is positioned within carveout <NUM>. Latch mechanism <NUM> is slid downwardly within carveout <NUM> with the laterally outward extending ends of pins <NUM> sliding in slots <NUM> until they reach holes <NUM>. Pins <NUM> are slightly compressed inwardly while sliding in slots <NUM> and once latch mechanism <NUM> is pressed into a fully seated position, pins <NUM> are disposed in holes <NUM>. When pins <NUM> are disposed within holes <NUM>, the latch mechanism is secured within carveout <NUM>.

Those skilled in the art will recognize that the primary function of latch mechanism <NUM> is to secure two bodies to one another. In order to perform this function, latch <NUM> is configured to selectively engage a step <NUM>, such as that shown in <FIG>. More specifically, the primary hook <NUM> and the secondary hook <NUM> are configured to separately engage step <NUM> at different locations thereof. Still further, the primary tooth <NUM> and the secondary tooth <NUM> are configured to engage step <NUM>. Still further, the primary tooth <NUM> is configured to engage an upper portion <NUM> of step <NUM> and the secondary tooth <NUM> is configured to engage a lip <NUM> of step <NUM>. With reference to <FIG>, <FIG> and <FIG>, body <NUM> includes a rectangular cutout opening <NUM> formed on each lateral side near the bottom thereof. Body <NUM> includes step <NUM> which may have a substantially rectangular cross-sectional shape and which extends between opposite side surfaces of cutout openings <NUM>. Step <NUM> may also be attached to the inner surface of cutout opening <NUM> via two connecting structures 53a to create three rectangular openings. Lip <NUM> is formed adjacent the lower surface of step <NUM> (at the top in the bottom view of <FIG>) and extends across the middle rectangular opening. Lip <NUM> is located generally opposite upper portion <NUM>.

<FIG> shows a second embodiment of the latch mechanism <NUM>. This second embodiment <NUM> is different from the first embodiment <NUM> in that the housing <NUM> is not relatively compact. Instead, housing <NUM> is additionally configured to be a lid of a container. In this second embodiment, the latch <NUM> is identical to the latch in the first embodiment. Moreover, the latch <NUM> of the second embodiment also functions identically to that of the first embodiment. <FIG> shows the latch mechanism <NUM> of the second embodiment positively securing two containers together.

<FIG> shows yet a third embodiment from the latch mechanism <NUM>. This third embodiment is different from the first embodiment <NUM> in that the housing <NUM> is additionally configured to be a stackable body. Housing <NUM> may also include a step <NUM> configured to be engaged by another latch mechanism. In this third embodiment, the latch <NUM> is identical to that of the first embodiment. Moreover, the latch <NUM> of the third embodiment also functions identically to that of the first embodiment. <FIG> shows the latch mechanism <NUM> of the third embodiment positively securing two stackable bodies together.

Turning now to <FIG>, the function of the latch mechanism <NUM> of the present invention positively coupling two bodies together will now be explained. <FIG> shows the latch mechanism <NUM> of the first embodiment coupling to containers together. For ease of reference, the top and bottom containers will be referred to using the identical reference numerals with the exception that the top container will include an "a", while the bottom container will include a "b".

Those skilled in the art will recognize that with the latch mechanism <NUM> of the first embodiment, body 46a will be coupled to lid 48b. As seen in <FIG>, the first step is to position body 46a above lid 48b. Body 46a should be positioned such that step 50a is above the primary hook <NUM>, and more specifically, above the step receiving surface <NUM>. When properly positioned, body 46a can be pressed downward so that step 50a engages the step receiving surface <NUM>. The application of downward force may also be achieved under the natural weight of body 46a. Step receiving surface <NUM> is angled so that when step 50a applies force thereto, latch <NUM> rotates against bias <NUM> toward its second position. Eventually, latch <NUM> rotates into its second position wherein the primary hook <NUM> is substantially obscured by the housing <NUM>. When this occurs, latch <NUM> is displaced such that step 50a can move beneath the primary hook <NUM>.

As shown in <FIG>, when step 50a is beneath primary hook <NUM>, bias <NUM> automatically rotates latch <NUM> back to its first position. Primary hook <NUM> extends over upper portion 57a of step 50a with primary tooth <NUM> extending laterally inward of step 50a and generally into the middle rectangular opening. Any upward motion of body 46a will cause the primary hook <NUM> to engage the top surface of step 50a and therefore upward motion is precluded. And any inward lateral movement of body 46a relative to lid 48b is precluded by the engagement of primary tooth <NUM> on the side wall of upper portion 57a of step 50a. At this point, body 46a and lid 48b are positively coupled together by latch mechanism <NUM>. (See <FIG>. ) Those skilled in the art will recognize that horizontal movement of body 46a will not free it from the latch mechanism <NUM> as such horizontal movement is limited by the primary tooth <NUM>. Moreover, a second latch mechanism positioned on the other side of lid 48b may further limit horizontal movement of body 46a. Still further, as shown in <FIG>, body <NUM> may include one or more feet <NUM>. Feet <NUM> may be configured to be disposed into corresponding depressions <NUM>, which may be found in lid <NUM>.

When an operator wishes to release body 46a from lid 48b, she will apply pressure to the operator surface <NUM>. In so doing, latch <NUM> is once again rotated against bias <NUM> into its second position. As step 50a is still positioned beneath primary hook <NUM>, rotating latch <NUM> to its second position causes the secondary hook <NUM> to engage step 50a. More specifically, the secondary tooth <NUM> engages the lip 58a of step 50a. As seen in <FIG>, the engagement of secondary tooth <NUM> to lip 58a is sufficient to positively hold latch <NUM> in its second position. However, since the length of secondary tooth <NUM> is small as compared to the overall length of step <NUM>, the engagement of tooth <NUM> and lip 58a is insufficient to secure body 46a on lid 48b. Therefore, an operator may move body 46a upward to free it from lid 48b. In order to improve the ease in which the secondary tooth <NUM> may be disengaged from the lip 58a, the secondary hook <NUM> and/or the lip 58a may be flexible.

Claim 1:
A container system including at least two containers (<NUM>), and characterized in that each container (<NUM>) comprises:
a carveout (<NUM>) formed adjacent an upper surface of the container (<NUM>);
a step (<NUM>) formed adjacent a lower surface of the container, said step including an upper surface portion (<NUM>) and a lower lip (<NUM>);
a latch (<NUM>) pivotally disposed in said carveout (<NUM>), said latch (<NUM>) including a first hook (<NUM>) having a first tooth (<NUM>) extending therefrom and a second hook (<NUM>) having a second tooth (<NUM>) extending therefrom;
wherein, said first said container is stackable on a second said container with said latch (<NUM>) of said second container disposed adjacent said step (<NUM>) of said first container, and said latch (<NUM>) is pivotable between a first position in which said first hook (<NUM>) overlies said step (<NUM>) of said first container and said first tooth (<NUM>) extends along a side surface of said step (<NUM>) of said first container to thereby secure said containers from moving relative to each other, and a second position in which said first hook (<NUM>) does not overlie said step (<NUM>) of said first container and said second tooth (<NUM>) engages said lower lip (<NUM>) of said step (<NUM>) of said first container to secure said latch (<NUM>) in said second position.