Latch Mechanism For A Child-Resistant Storage Case

Abstract

A latch mechanism for a child-resistant storage case has a seal bead between the lid and body of the storage case. The latch mechanism includes a latch tab extending downward from the lid that must be simultaneously pivoted inward and pressed upward to release the lid. The latch tab acts as a lever arm to locally deform the adjacent portions of the lid and seal, and thereby more easily release the seal when the latch tab is pressed upward.

Description

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates generally to the field of latches for storage cases. More specifically, the present invention discloses a latch mechanism for a child-resistant storage case that requires the user to simultaneously press inward and upward on the latch tab to pivot the latch tab and thereby open the lid of the storage container.

Statement of the Problem

A wide variety of child-resistant storage cases have been invented in the past. These typically include features requiring a larger hand size or greater dexterity than is usually found in small children in order to open the storage case. For example, some child-resistant storage cases require the user to simultaneously press multiple latches to open the case. Some storage cases are specifically designed so that the spacing between the latches exceeds the span of a small child's hand.

Other child-resistant storage cases rely on requiring a combination of user actions that are counter-intuitive or require adult dexterity. In particular, a combination of multiple actions or forces are often required. For example, some child-resistant storage cases use a latch mechanism that requires the user to simultaneously exert inward and downward forces on a latch member while lifting upward on the lid.

On the other hand, many senior citizens and persons with disabilities or limited hand strength find it challenging to use some types of child-resistant containers due the strength or dexterity required to open the lid. Thus, the need for effective child-resistant features in a storage case must be balanced against the need for a latch mechanism that can be readily understood and used by adults.

The prior art in this field includes boxes, storage cases and similar enclosures with latch mechanisms requiring that the user simultaneously exert an inward force, or a combination of forces or moments to release the lid. For example, Masumoto (U.S. Pat. No. 8,648,264) shows a terminal box that requires a simultaneous “up and in” action to release the lid. Lids with O-rings or other types of seals are also well known.

Somewhat similarly, Keung (U.S. Pat. No. 7,721,907) has a lid with a latch arm that must be pressed radially inward and moved upward to release the lid. The lid and base have complementary beads for releasable snap retention of the lid.

Solution to the Problem

The present invention addresses these concerns by providing a latch mechanism for a child-resistant storage case that requires the user to simultaneously press upward on the latch tab and pivot the latch tab inward to open the lid of the storage container. The particular structure employed in the present storage case is unique in that it includes both a latch tab with a protruding catch, and a peripheral seal bead that is disengaged by pivoting the latch tab inward and then lifting the lid of the storage case.

SUMMARY OF THE INVENTION

This invention provides a latch mechanism for a child-resistant storage case having a seal bead between the lid and body of the storage case. The latch mechanism includes a latch tab extending downward from the lid that must be simultaneously pivoted inward and pressed upward to release the lid. The latch tab acts as a lever arm to locally deform the adjacent portions of the lid and seal, and thereby more easily release the seal when the latch tab is pressed upward.

These and other advantages, features, and objects of the present invention will be more readily understood in view of the following detailed description and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more readily understood in conjunction with the accompanying drawings, in which:

FIG. 1 is a top axonometric view of an embodiment of the present storage case with the lid 20 partially open.

FIG. 2 is a top axonometric view of the storage case corresponding to the FIG. 1 with the lid 20 fully open.

FIG. 3 is a top axonometric view of the storage case corresponding to FIGS. 1 and 2 with the lid 20 closed.

FIG. 4 is a top view of the storage case corresponding to FIG. 3.

FIG. 5 is a right side view of the storage case corresponding to FIG. 2.

FIG. 6 is a vertical cross-sectional view of the storage case corresponding to FIG. 3.

FIG. 7 is an enlarged detail vertical cross-sectional view of the latch mechanism of the storage case corresponding to FIG. 6.

FIG. 8 is a detail vertical cross-sectional view of the latch mechanism corresponding to FIG. 7 with arrows showing the required direction of applied force on the latch tab 30, inward and upward.

FIG. 9 is a detail vertical cross-sectional view of the latch mechanism corresponding to FIGS. 7 and 8 showing local deformation to begin to release the seals 15, 25.

FIG. 10 is a detail vertical cross-sectional view of the latch mechanism corresponding to FIGS. 7-9 after the latch tab 30 and seals 15, 25 have been released.

FIG. 11 is a top axonometric view of an alternative embodiment of the storage case having a shallower body 10.

FIG. 12 is a top axonometric view of another alternative embodiment of the storage case having a deeper body 10.

FIG. 13 is a top axonometric view of another alternative embodiment of the storage case having a still deeper body 10.

FIG. 14 is a top axonometric view of another alternative embodiment of the storage case having a generally rectangular shape.

FIG. 15 is a top axonometric view of another alternative embodiment of the storage case having a generally rectangular shape and a deeper body 10.

FIG. 16 is a top axonometric view of another alternative embodiment of the storage case having a side tab 18 extending laterally from body 10 of the storage case adjacent to the latch tab 30.

FIG. 17 is top axonometric view of another alternative embodiment of the storage case generally corresponding to the FIG. 16, but with a deeper body 10.

DETAILED DESCRIPTION OF THE INVENTION

Turning to FIG. 1, a top axonometric view is provided showing an embodiment of the present storage case with the lid 20 partially open. FIG. 2 is a top axonometric view of the storage case with the lid 20 fully open. FIG. 3 is a top axonometric view of the storage case with the lid 20 closed. FIG. 4 is a corresponding top view of the storage case. FIG. 5 is a right side view of the storage case corresponding to FIG. 2.

This storage case has a body 10 with a bottom surface and peripheral side walls to form an interior chamber for storing objects or material. The upper edges of the peripheral side walls define an opening at the top of the body 10 for providing access to the interior chamber.

A lid 20 with a top surface and peripheral side walls can be used to cover and seal the opening of the body 10, and thereby close the storage case as shown in FIG. 3. The lid 20 can be connected to the body 10 of the storage case by a living hinge 16 (e.g., a thin strip of flexible plastic) along the rear of the storage case.

Both the body 10 and lid 20 can be molded as a single plastic piece, as illustrated in FIGS. 2 and 4-6. For example, the body 10 and lid 20 can be molded with relatively thin plastic walls to create a storage case with thin peripheral side walls, and top and bottom surfaces enclosing the interior chamber when the lid 20 is closed. Optionally, stacking ribs can also be included for enhanced structural rigidity in key areas of the storage case; to ensure proper nesting of parts when stacked; or to secure internal accessories within the storage case, such as trays or dividers.

A lower flange 12 projects outward from the front or side wall of the body 10 of the storage case as shown in FIG. 1. The lower flange 12 is oriented horizontally and is spaced a predetermined distance below the top rim of the body 10 of the storage case. A latch opening 14 passes vertically through this lower flange 12.

A flexible seal 15, 25 is provided between at least a portion of the top rim of the body 10 and the lid 20 to provide a close fit between the body 10 and lid 20 when the lid 20 is in the closed position. In particular, a flexible seal 15 runs along at least a front portion of the outside perimeter of the top rim of the body 10. In one embodiment of the present invention, the seal 15 extends circumferentially about the top rim, as shown in the drawings. The upper portion 17 of the walls of the body 10 of the storage case (e.g., above the flange 12 and adjacent to the seal 15) could have a reduced thickness to enhance its flexibility and increase the flexibility of the circumferential seal 15. Preferably, this flexible upper wall 17 extends about the top rim of the body 10 and reduces the force required to release the seal 15, as will be discussed below.

A complementary flexible seal 25 runs along at least the front portion of the interior of the lid 20. Here again, the lid seal 25 preferably extends circumferentially about the interior of the lid 20 as shown in FIG. 2. The seals 15, 25 abut when the lid 20 is closed to provide an interference seal between the body 10 and lid 20 as shown in FIGS. 6 and 7. It should be noted that the seal 25 on the lid 20 can be a protruding bead and/or a circumferential recess that engages the protruding bead seal 15 on the outside of the upper wall 17 of body 10 of the storage container. Preferably, the storage case employs a single-piece integral seal featuring a back-to-back compression design due to compression interference between a mating female seal bead 25 on the interior of the lid 20 and a male seal bead 15 on the outside of the body 10. However, the relative positions of the seals 15, 25 could be reversed so that the bead is on the lid 20 and the recess is on the body 10 of the storage case.

The lid 20 also has an upper flange 22 projecting outward from its front or side wall in vertical alignment with the lower flange 12 when the lid 20 is closed as depicted in FIG. 3. A latch tab 30 extends downward from the upper flange 22 and is aligned to be received by and pass through the latch opening 14 in the lower flange 12 as the lid 20 is closed, as shown in FIGS. 3, 6 and 7.

As illustrated in FIGS. 1, 5 and 7, the latch tab 30 has at least one catch 34 on its front face. When the lid 20 is closed and the latch tab 30 is in its resting state shown in FIG. 7, the catch 34 protrudes forward sufficiently to come into contact with the lower surface of the lower flange 12 and thereby prevent the lid 20 from opening.

Preferably, a second protrusion 32 protrudes from the front of the latch tab 30 below the catch 34. This second protrusion 32 in combination with the catch 34 produce an audible or haptic double click when the case is closed, thereby enabling the owner to positively sense when the storage case has been fully latched.

Pressing inward on the latch tab 30 causes the latch tab 30 to pivot and moves the catch 34 and second protrusion 32 rearward to pass through the opening 14 in the lower flange 12 as shown in FIGS. 8-10. The second protrusion 32 also provides a prominent surface for the user to push upward while pushing inward on the latch tab 30. Preferably, the leading and trailing edges of the second protrusion 32 are chamfered to generate a haptic response, but allow the second protrusion 32 to pass through the latch opening 14 with minimal resistance and enable the catch 34 to secure the lid 20 closed.

The present storage case requires simultaneous inward and upward forces on the latch tab 30 as indicated by the force arrows in FIGS. 7-9, which makes it difficult for a child to open the storage case. In other words, the latch tab 30 must be simultaneously pivoted inward and pushed upward to release the lid 20 from the body 10 of the storage case.

In its resting state, the lid 20 is held closed by both the seal 15 on the body 10 engaging the seal 25 on the inside of the lid 20, and the catch 34 on the latch tab 30 that comes into contact with the bottom of the lower flange 12 on the body 10 of the storage case. Simply pushing up on the latch tab 30 does not defeat the latch because the catch 34 contacts the bottom surface of the lower flange 12 extending from the body 10 of the storage case. Simply pushing in on the latch tab 30 does not defeat the latch because the seal beads 15, 25 remain engaged and resist the upward force.

When the latch tab 30 is simultaneously pivoted inward and pushed upward, the adjacent front edge of the lid 20 is deformed outward as the latch tab 30 rotates inward. This also tends to deform and dislodge the seal 15 on the upper front edge of the body 10 from the seal 25 on the inside of the front of the lid 20, as shown in FIG. 9. After being pivoted inward, the latch tab 30 (and its catch 34 and protrusion 32) can pass upward through the latch opening 14 in the lower flange 12 in response to an upward force exerted by the user to release the lid 20 as shown in FIG. 10.

This pivoting action can be implemented in a variety of ways depending on the shapes, dimensions and proportions of the components of the storage case. For example, the front inside edge 23 of the lid 20 adjacent to the base of the latch tab 30 can act as a fulcrum for the latch tab 30 and the front edge of the lid 20. This locally deforms the adjacent front upper edge (i.e., adjacent to the seal bead 25) of the lid 20 outward as the latch tab 30 rotates inward and may also locally deform the adjacent upper portion of the front wall of the container 10 inward (i.e., adjacent to the seal bead 15). Both of these local deformations tend to partially separate the seal beads 15, 25 in the region adjacent to the latch tab 30. In turn, this reduces the upward force that must be exerted on the latch tab 30 to open the lid 20.

In some embodiments of the present invention, the lower surface 26 of the upper flange 22 could maintain contact with the upper surface of the lower flange 12 and effectively function as a fulcrum for pivoting the latch tab 30 inward. Here again, the resulting local deformations in the front edge of the lid 20 and the adjacent upper portion of the front wall of the container 10 tend to partially separate the seal beads 15, 25 and thereby reduce the upward force required to open the lid 20.

In some embodiments of the present invention, the region of contact between the seal beads 15, 25 functions as a fulcrum. In this configuration, pivoting the latch tab 30 inward induces a moment about the seal beads 15, 25 that tends to partially separate the seal beads 15, 25 and reduces the upward force required to open the lid 20.

As previously noted, the entire storage container can be molded from polymers as a single piece using conventional injection molding techniques. The interior shapes of the lid 20 and body 10 of the storage case and drafting of their side walls allow a plurality of storage cases to be nested together to facilitate compact storage and automated handling. Selected regions of the front wall of the lid 20 or the upper front wall of the container 10 can be formed with a reduced thickness to enhance flexibility and thereby reduce the force required to operate the latch mechanism.

In addition, the present storage case may include clearance within the lid 20 for a tamper-evident film or foil to be applied to the base 10 of the container. The top of the seal 15 should have a sufficient width to successfully adhere this tamper-evident film or foil to the body of the storage case.

FIGS. 11-13 show alternative embodiments of the storage case having bodies 10 of various depths and storage capacities. These embodiments have bodies 10 with side walls of various drafts and dimensions but have lids 20 and openings of the same size. This enables much of the same hardware to be used in handling all of these storage cases. Similarly, FIGS. 14 and 15 show alternative embodiments of the storage case having a generally rectangular shape and bodies 10 of different depths. It should be understood that the storage case could have other shapes and proportions.

FIGS. 16 and 17 show an alternative embodiments of a generally rectangular storage case with a side tab 18 extending laterally outward from the side of the body 10 of the storage case adjacent to the latch tab 30. The user can support the storage case with the left hand holding the left side of the storage case. The right thumb is used to press inward and upward on the latch tab 30, while the right index finger presses downward on the side tab 18. This configuration provides a more ergonomic grip and simplifies the motion required to release the latch mechanism.

The embodiments illustrated in FIGS. 16-17 also replace the front flange 22 (shown in the earlier embodiments) with a horizontal tab 36 projecting forward from and extending across the upper portion of the latch tab 30. The latch tab 30 extends downward directly from the front of the lid 20. When the lid 20 is in its closed position, the bottom of the horizontal tab 36 abuts the top surface of the flange 12 on the body 10 of the storage case. Testing has indicated that small children may attempt to defeat similar latch mechanisms by biting the latch tab 30 and flange 12. By simultaneously exerting an upward force on the lower end of the latch tab 30 with the mandibular teeth and exerting a downward force on the flange 12 with the maxillary teeth, a child could potentially force the latch mechanism to open. This possibility is avoided by covering the flange 12 with the horizontal tab 36 in the closed position. Since the horizontal tab 36 and the latch tab 30 are both firmly secured to the lid 20, the compressive force of a bite is carried entirely by the horizontal tab 36 and latch tab 30. Biting on these surfaces does not result in a net upward force on the latch tab 30, and therefore does not tend to open the latch mechanism.

It should also be understood that the relative positions of the lid, base and the components of the latch mechanism could be readily reversed. These alternative embodiments should be interpreted as being within the scope of the present invention.

The above disclosure sets forth a number of embodiments of the present invention described in detail with respect to the accompanying drawings. Those skilled in this art will appreciate that various changes, modifications, other structural arrangements, and other embodiments could be practiced under the teachings of the present invention without departing from the scope of this invention as set forth in the following claims.

Claims

1. A storage case comprising: a body having a chamber for storage with a top rim;a flange extending outward adjacent to the top rim of the body;a latch opening in the flange;a lid for closing the chamber of the body;a latch tab extending downward from the lid to pass through the latch opening when the lid is in the closed position, with a catch to secure the latch tab in the latch opening in the closed position; anda flexible seal between at least a portion of the top rim of the body and the lid when the lid is in the closed position;wherein pressing inward and upward on the latch tab releases the catch of the latch tab and pivots the latch tab to deform adjacent portions of the lid and seal, thereby releasing the seal and lid from the closed position.

2. The storage case of claim 1 wherein the seal comprises a flexible beaded seal on one of the lid and body, and a complementary recess along the other of the lid and body.

3. The storage case of claim 1 further comprising a flexible upper wall extending about the top rim of the body, and wherein the flexible seal comprises a beaded seal on the flexible upper wall.

4. The storage case of claim 3 wherein the seal comprises a bead on the outside of the flexible upper wall and a complementary recess on the inside of the lid for engaging the bead.

5. The storage case of claim 1 wherein the adjacent portion of the lid is deformed outward to release the seal by pressing inward and upward on the latch tab.

6. The storage case of claim 1 wherein the lid further comprises a flange extending outward in vertical alignment with the latch opening, and wherein the latch tab extends downward from the flange of the lid and through the latch opening when the lid is in a closed position.

7. The storage case of claim 1 further comprising a hinge between the lid and body allowing the lid to move between a closed position and an open position.

8. The storage case of claim 1 further comprising a side tab extending laterally outward from body adjacent to the latch tab.

9. A storage case comprising: a body having a chamber for storage with a top rim;a flexible upper wall extending about the top rim of the body;a flange extending outward adjacent to the top rim of the body;a latch opening in the flange;a lid for closing the chamber of the body;a latch tab extending downward from the lid to pass through the latch opening when the lid is in the closed position, with a catch to secure the latch tab in the latch opening in the closed position; anda flexible seal between at least a portion of the flexible upper wall of the body and the lid when the lid is in the closed position;wherein pressing inward and upward on the latch tab releases the catch of the latch tab and pivots the latch tab to deform adjacent portions of the lid, flexible upper wall and seal, thereby releasing the seal and lid from the closed position.

10. The storage case of claim 9 wherein the seal comprises a flexible beaded seal on one of the lid and the flexible upper wall of the body, and a complementary recess along the other of the lid and the flexible upper wall of the body.

11. The storage case of claim 9 wherein the flexible seal comprises a beaded seal on the flexible upper wall of the body.

12. The storage case of claim 11 wherein the seal comprises a bead on the outside of the flexible upper wall and a complementary recess on the inside of the lid for engaging the bead.

13. The storage case of claim 9 wherein the adjacent portion of the lid is deformed outward to release the seal by pressing inward and upward on the latch tab.

14. The storage case of claim 9 wherein the lid further comprises a flange extending outward in vertical alignment with the latch opening, and wherein the latch tab extends downward from the flange of the lid and through the latch opening when the lid is in a closed position.

15. The storage case of claim 9 further comprising a side tab extending laterally outward from body adjacent to the latch tab.

16. The storage case of claim 9 further comprising a hinge between the lid and body allowing the lid to move between a closed position and an open position.