RUGGED PORTABLE CASE

Cross-Reference to Related Application

This application claims the benefit of U.S. provisional patent application Serial No. 60/886,570, filed January 25, 2007, the entire disclosure of which is hereby incorporated by reference.

Field of the Invention

This invention relates to a rugged case for portable devices and to a method of constructing a portable case.

Background

Many portable devices, particularly electronic equipment, are desirably housed in an industrially rugged, inexpensive, and durable case for protection against impacts during use and transportation. Previous attempts to construct such a case typically have included heavier, stronger, and stiffer components, often of metal. The resulting case often is expensive because of the added material and workmanship required for its construction.

Rugged cases for portable devices typically have a handle that extends from one side. The cases also may include control elements, such as switches, dials, displays, etc., exposed on an exterior surface, often with adjacent brackets extending from the case to provide some protection against impacts to the control elements. Protruding elements make cases more difficult to stack and transport, however.

Summary

An aspect of the invention relates generally to a portable case that is rugged, relatively inexpensive, and durable, while also being substantially free of any protruding elements that would hinder stacking or transporting the case. Any elements that extended outside the case also would be exposed to a greater risk of damage.

Another aspect relates to a portable case that includes a pair of side walls and a tubular housing having opposing open ends. The housing is interposed between the side walls so that the side walls close the open ends of the housing, and both side walls extend beyond the housing in at least one direction. In general, the side walls are connected together by elements extending therebetween, including reinforcing members extending between and fastened to the side walls.

According to another aspect of the invention, a portable case includes a pair of generally planar, parallel side walls attached together by a plurality of cylindrical rods, and a tubular housing having opposing open ends and a generally rectangular cross-sectional shape formed by a generally planar top wall, a generally planar bottom wall spaced from and generally parallel to the top wall, and a pair of generally planar, spaced-apart, generally parallel end walls. The end walls generally are perpendicular to the top wall and the bottom wall. The housing is interposed between the side walls so that the side walls close the open ends of the housing. Both side walls extend beyond the housing in all directions.

Other aspects of the invention relate to a method of constructing a portable case, comprising the following steps: (a) constructing a tubular housing having opposing open ends, and (b) closing the open ends of the housing by interposing the housing between a pair of side walls so that both side walls extend beyond the housing in at least one direction.

Another aspect of the method may also include the step of attaching the housing to the side walls using ribbed nails, the removal of which will provide evidence of tampering.

Brief Description of the Drawings

FIG. 1 is a schematic perspective end view of an exemplary portable case provided by the present invention.

FIG. 2 is a schematic perspective side view of the portable case shown in FIG. 1 , with hidden lines to show some of the hidden components.

FIG. 3 is a schematic perspective end view of a plurality of portable cases stacked together.

FIG. 4 is a top plan view of the portable case shown in FIG. 1.

FIG. 5 is a cross-sectional elevation view of the case shown in FIG. 1 , as seen along lines 5-5 in FIG. 4.

FIG. 6 is a schematic sectional view of a fastener securing a housing portion of a portable case provided by the present invention to a side wall portion.

FIG. 7 is a schematic sectional view of a fastener securing a handle portion of a portable case provided by the present invention to a side wall portion.

FIG. 8 is a schematic cross-sectional view of another fastener securing a handle portion of a portable case provided by the present invention to a pair of spaced-apart side wall portions.

Detailed Description

Referring now to the drawings, and initially to FIGS. 1-5, a portable case 20 that is rugged, relatively inexpensive, and durable is illustrated. The case 20 also is substantially free of any protruding elements that would hinder stacking or transporting the case 20. Elements that protrude from the case 20 are more likely to be damaged than if protected, and thus the case 20 protects itself and its contents.

The case 20 includes a housing 22 for a portable device 23, such as a computer, an ionizer, etc., and the housing 22 is supported between a pair of side walls 24 of the case 20 that extend beyond the housing 22 to provide a crush zone 30. The crush zone 30, the portion of the case side walls 24 that extends beyond the housing 22, protects the housing 22 and its contents from impact, particularly on its edges where damage is most likely to occur, such as from being dropped. The case side walls 24 are connected together and reinforced by multiple reinforcing members 32 that strengthen the case 20 and help to prevent or minimize racking (twisting) or other distortion that might otherwise occur from an impact. The reinforcing members 32 also double as handles for lifting and moving the case 20. As is seen in FIGS. 1 and 2, the housing 22 floats between the side walls

24 of the case 20 and any controls or connectors for the portable device 23, for example, typically are mounted to the housing 22 so that they are effectively

recessed between and thereby protected by the case side walls 24. By providing access to the portable device in the housing 22 in an area between the case side walls 24, particularly in an area protected by crush zones 30, the outer surface of the case side walls 24 typically remains substantially free of any protrusions that would hinder stacking, while also protecting the controls and connectors for the portable device. Thus the case 20 can be stacked on top of another object, support, or even another case.

FIG. 3 shows a plurality of cases 20 stacked together side-by-side and one on top of another. Such a stack can have any orientation, and certainly the cases 20 may be arranged in other configurations.

The elements of the portable device 23, such as a personal computer or an ionizer, for example, are mounted in the housing 22, and any controls and input and output connectors generally are accessible from outside the housing 22 between the case side walls 24. The controls and connectors may include one or more switches or other input devices, a display or other output devices, and a power cord extending from the housing 22 to provide electrical power to the portable device, for example, all of which may be accessible between the case side walls 24. Accordingly, one or more walls of the housing 22 may have one or more holes to provide access to and from the internal components of the portable device 23. The controls typically are not accessible from outside the case side walls 24, where they would be more exposed and thus more susceptible to damage, although it may be possible to reach inside the case 20 to access the controls to operate or to adjust them. Elements protruding beyond the side walls 24 also would make it more difficult to stack multiple cases side-by-side or on top of one another.

As shown in FIG. 5, the housing 22 is generally box-shape, e.g., rectangular, with opposite open ends. In other words, the housing 22 can be rectangular and tubular. The housing 22 may have any cross-sectional shape, although a square or rectangular shape facilitates both assembling the housing 22 and mounting components of the portable device 23 in the housing 22.

In the illustrated embodiment the housing 22 has a generally rectangular cross-sectional shape, with a top wall 40, a bottom wall 42 generally parallel to

and spaced from the top wall 40, and a pair of parallel, spaced-apart end walls 44. The housing end walls 44 generally are perpendicular to the top wall 40 and the bottom wall 42 of the housing 22. The housing end walls 44 may be inset from the ends of the housing top wall 40 and bottom wall 42. The opposing open ends of the housing 22 are closed by the case side walls 24, which extend beyond the dimensions of the housing 22 in at least one direction. In the event that the case 20 is dropped, the crush zone 30 provided in the case side walls 24 provides sacrificial material that can be cut, crushed, bent, crumpled, dented, etc., to absorb the impact force and protect the housing 22 and the portable device 23 in the housing 22. In the illustrated embodiment the case side walls 24 extend beyond the housing 22 in all directions an approximately equal amount. One or both of the case side walls 24 may not extend beyond all sides of the housing 22, however, depending on the application. If a device is more likely to fall to one side, for example, a crush zone may not be needed on an opposite side of the housing.

In the embodiment shown in FIG. 5, the case side walls 24 and the walls 40, 42, and 44 of the housing 22 are all formed from planar sheets or plates. The illustrated design does not require close tolerances and thus is very forgiving of variations in wall dimensions. These housing walls 40, 42, and 44 also could be formed by an extrusion or molding or other process, either as separate elements or as a single unit forming multiple walls. This potentially includes forming one or more walls 40, 42, and 44 of the housing 22 integrally with one or both of the case side walls 24.

The case side walls 24 and the housing 22 are made of a resilient, impact- absorbing material. While portions of the housing 22 and case side walls 24 could be molded into a shape that defines substantially all of the case, sheet materials also are readily available and easily cut to size with minimal tooling for much lower cost. Exemplary materials include a polyvinyl foam or a polyethylene. Polyethylene also is used to make cutting boards, for example, and is sufficiently rigid to provide structural support, but is sufficiently soft and resilient to enable the side walls to absorb cuts and impacts with minimal transmission of force to the housing 22. Polyethylene also is readily machined, and is easily cut with

commonly-available and relatively inexpensive saws; no special tooling is required. Further, polyethylene also can be colored such that the color extends evenly all the way through. Thus any scratches or dents will be less noticeable and no finishing material has to be applied during manufacture. The housing 22 may be made of a material that is stiffer than the case side walls 24, which may require greater impact-resistance than the housing 22 does. Additionally, for portable electrical devices, at least one of the housing 22 and the case side walls 24 may be made of electrically non-conductive dielectric materials. If the surface is properly textured, such as a pebble grain polyethylene sheet, polyethylene can dissipate a static charge relatively quickly, thereby preventing the buildup of a charge on the case 20.

The housing 22 can be attached to the case side walls 24 with an adhesive or a mechanical fastener, such as a screw or nail, or a combination thereof, suitable for use with the housing 22 and case side wall 24 materials. Typically, at least the end walls 44 and the bottom wall 42 of the housing 22 are attached to the case side walls 24. The top, bottom and end walls 40, 42, and 44 of the housing 22 can be attached to each other as well. For example, the housing end walls 44 may be attached to at least one of the housing top wall 40 and bottom wall 42. A ribbed, stainless steel ring-shank nail 50 has been found to be an exemplary means for connecting the top, bottom, and end walls 40, 42, and 44 of the housing 22 to the side walls 24 of the case 20, and an example of the housing top wall 40 secured in this manner to one of the case side walls 24 is shown in FIG. 6. In addition to or in place of the ring shank nail 50 or other mechanical fastener, a resilient adhesive, such as rubber cement or a silicone adhesive, which provides additional shock and vibration resistance at the interface between the case side walls 24 and the housing 22, may be used.

If nails, for example, are employed between the housing 22 and the case side walls 24, the nails can be driven in until flush or inset relative to the surface of the case side wall 24, or other efforts can be made, so that attempts by unauthorized persons to open the case will be evident. For example, due to the nature of ring shank nails and their interaction with the polyethylene side walls 24 of the case 20 and housing walls 40, 42, and 44, the hole for such a nail will be

enlarged if the ring shank nail were pulled out. Consequently, the side walls 24 cannot be removed and then re-attached with the same nails. The enlarged hole may be suitable for a next-larger size ring-shank nail, however. Even if removal is unsuccessful, the polyethylene surface of the case side walls 24 is soft enough that it probably will be marred by tools used in attempting to remove the nails and thus indicate tampering.

Another way to support the housing 22 between the case side walls 24 is to form, such as by molding, milling, or routing, one or more grooves or slots in the inner faces of the case side walls 24 to receive portions of the housing walls 40, 42, and 44. If the side walls 24 of the case 20 are held together by connecting elements, including the reinforcing members 32, the grooves might support the housing 22 without any fasteners between the walls 40, 42, and 44 of the housing 22 and the side walls 24. FIG. 6 shows both a groove 52 in the side wall 24 and the ring shank nail 50 securing the top wall 40 of the housing 22 in the groove 52. Other slots and holes may be formed in the case side walls 24 or the housing 22 to accept attachments or accessories for the portable device 23 (FIG. 5). For example, parallel slots in the facing inner surfaces of the case side walls 24 may allow a fixture to slide down in front of an end wall 44 of the housing 22 and mate therewith. If the portable device 23 is an ionizer, the fixture may support the end of a hose, for example, for providing air to the ionizer or guiding ionized air to a remote location.

To reinforce the case side walls 24 and thus better protect the housing 22, the case side walls 24 are held together by connecting elements extending therebetween, including the aforementioned reinforcing members 32 and any fasteners used to secure them to the case side walls 24. The reinforcing members 32 may be integrally formed with the housing 22 or the case side walls 24 or a combination thereof. The reinforcing members 32 also help to keep the case 20 from racking, twisting, warping, bending, or otherwise changing shape from age, environmental temperatures or from an impact, such as from being dropped. In the illustrated embodiment, the reinforcing members 32 have a cylindrical shape and are spaced from the housing 22 so that they form handles

for lifting and otherwise moving the case 20, and also generally are spaced from the edges of the case side walls 24.

Particularly when used as handles, the reinforcing members 32 generally are connected to the case side walls 24 in the crush zone 30 outside the housing 22. Alternatively, one or more reinforcing members 32 may extend through the housing 22. In general, the reinforcing members 32 typically have characteristics that provide a stronger anchorage for screws or other fasteners than the housing walls 40, 42, and 44. For example, the reinforcing members may be made of an acetyl or another sufficiently strong material. The case 20 generally includes at least two reinforcing members 32 on each of two opposing sides of the housing 22. In the illustrated embodiment, three reinforcing members 32 are evenly spaced above the housing 22 and three reinforcing members 32 are evenly spaced below the housing 22. Exemplary reinforcing members, reinforcing rods or bars, have a cylindrical shape. The reinforcing members 32 may take other shapes, including rods or bars with different cross-sectional shapes, or plates or grids that extend over a greater proportion of one or more sides of the housing 22 for additional impact protection, generally at a cost of additional weight.

In an exemplary arrangement, such as that shown in the drawings, the reinforcing members 32 include cylindrical rods approximately 2.2 cm (about 7/8 inch) in diameter, spaced about 0.2 cm (about 1/16 inch) from the edges of the case side walls 24 and approximately 3.8 cm (about 1.5 inches) from the housing 22. Spacing the reinforcing members 32 from the housing enables someone to reach between a reinforcing member 32 and the housing 22 to grasp the reinforcing member 32 and use it as a handle. These sizes and dimensions are exemplary; others may be used.

The reinforcing members 32 may be secured to the case side walls 24 mechanically, with screws or nails, for example, or chemically with an adhesive, for example, or a combination thereof, as is suitable for use with the materials used for the case side walls 24 and the reinforcing members 32. Thus the connecting elements may include a screw 60 that extends through the case side walls 34 and into the reinforcing member 32, as shown in FIG. 7. An exemplary

screw is a stainless steel #10-size screw, commonly available in the United States. Equivalents are readily available. Alternatively, the reinforcing member 32 can take the form of a hollow tube 64 secured between the case side walls 24 by a bolt 66 extending therethrough, as shown in FIG. 8, for example. While any sufficiently strong screws or nails can be used, the reinforcing members 32 can be secured in such a manner as to provide tamper-resistance by employing tamper-resistant screws, flush or inset nail heads, or ring shank nails, for example. Tamper-resistant screws include features that hinder their removal with commonly available tools, such as Phillips-head and flat-head screwdrivers, hex or Allen wrenches, and crescent wrenches, among others. Such screws, sometimes referred to as security screws, typically require a specialized tool for inserting and removing the screw.

It is estimated that the portable case described herein, formed of polyethylene sheets and acetyl reinforcing rods nailed and screwed together as described, could support a portable device of about 22 to 90 kg (about 50 to 200 pounds).

The invention also is a method of constructing a portable case, comprising the following steps: (a) constructing a tubular housing having opposing open ends, and (b) closing the open ends of the housing by interposing the housing between a pair of side walls so that both side walls extend beyond the housing in at least one direction. Additional steps may include (c) reinforcing the case side walls by connecting the side walls together with multiple reinforcing members, which desirably in many instances can double as handles, and/or (d) attaching the housing to the side walls using ribbed nails, the removal of which will provide evidence of tampering. Further, the method may include a step of mounting control elements on the surface of the housing and recessing the housing between the side walls to protect the control elements from damage.

Although I have shown and described my invention with respect to a certain illustrated embodiment, equivalent alterations and modifications will be obvious to others skilled in the art as they read and thus come to understand this specification and the annexed drawings. Dimensions, materials, weights, etc., described herein are only exemplary and others may be used in the cases

provided in accordance with the invention. In particular regard to the various functions performed by the above described components, the terms (including a reference to a "means") used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment of the invention. In addition, while a particular feature of the invention may have been disclosed with respect to only one of the several embodiments, such features generally can be combined with one or more other features of any other embodiment as may be desired and advantageous for any given or particular application.