IMPACT PROTECTION ENCLOSURE FOR A MOBILE ELECTRONIC DEVICE
An add-on protective housing to improve protection of a portable electronic device. Certain embodiments include a hard external shell in the general conformation of the electronic device. The hard shell includes one or more aperture through which one or more control of the contained device may be operated. An energy distributing layer is disposed between the electronic device and the inner surface of the hard shell to space the device apart from the shell. Certain embodiments may provide fluid and/or dust resistance to the contained device.
1. The Field of the Invention
The present invention relates to impact-protecting add-on devices. In particular, a preferred embodiment forms an add-on enclosure to increase protection for a selected mobile electronic device from at least impact.
2. Related Art
Portable electronic devices are becoming smaller, more sensitive, and costly to replace, yet the current standard for protection is believed to be inadequate. Exemplary such electronic devices includes cell-phones. There are many commercially available housings structured to provide add-on protection for certain of such electronic devices, yet none have sufficiently addressed the need for impact protection.
Most protective cases for mobile electronic devices have been introduced in the form of scratch- and mar-resistant, add-on enclosures, with an emphasis on color, style or fashion. Many protective cases are designed to add a minimal amount of impact protection in the form of a stretch-to-fit silicone skin, which leaves the device most vulnerable to impact on the corners and edges of the device. Even fewer protective cases are designed to add impact, or drop protection as a main goal of the design. Examples of such protective cases are disclosed in U.S. Pat. No. 7,933,122 and US patent application 2010/0147737. Even the add-on cases disclosed in the aforementioned documents, and designed for impact protection, leave room for further improvement.
BRIEF SUMMARYThe invention may be embodied to provide an add-on enclosure to increase ruggedness of a commercially available portable electronic device. A preferred enclosure includes a hard shell configured in general agreement with the exterior of the electronic device. A workable enclosure includes six sides, including a front side, back side, top side, bottom side, left side, and right side. The sides generally define a first volume. One or more window is disposed in one or more of the sides to permit operation of at least one control of the electronic device when the electronic device is contained inside the shell. Preferred embodiments also include an energy distributing layer structured for disposition inside the shell and defining a second volume in which to receive the electronic device. Typically, the energy distributing layer is arranged to space a portion of the electronic device apart from direct contact with the shell.
A preferred hard shell includes a plurality of elements that may be assembled to form a uni-body enclosure. One such hard shell includes a tub and a cover. Uni-body enclosures can form very strong structures with efficient use of material. An exemplary hard shell structured according to certain principles of the invention is structured to contain a telephone and to carry a minimum 3-point load in excess of about 25 pounds, where the load is applied at the midpoint of a 4 inch span.
A preferred embodiment includes a cover, a top tub, and a bottom tub. A slide rail system of that embodiment is formed in combination between the cover, top tub, and bottom tub, and is configured to permit slide-assembly of each tub onto the cover. A detent-and-ramp structure is associated with such slide rail system, and is configured and arranged to resist sliding a tub from an installed position. Further, a push-button flex latch is carried by one tub and is configured and arranged to removably couple the top tub to the bottom tub when the tubs are in an assembled location on the cover. It is helpful to form a relief area in the energy distributing element to permit a user to impart a transverse deflection to the latch to permit separation of a tub from the cover.
A perimeter edge of a tub may includes a shelf and a cantilevered rim. One workable rim is adapted to overlap structure of a cooperating cover at a joint there-between. For example, a cantilevered flange can project from an inside surface of the cover and skirt a portion of the perimeter edge of the cover. The flange is advantageously arranged to overlap the rim at their mutual joint.
Sometimes, wall elements of a flange and a cooperating rim can carry retention structure, such as a plurality of cylinder-in-socket retention structures. Is such case, the retention structures are desirably configured to effect a snap-together connection between tub and cover to form a uni-body enclosure that can be assembled and disassembled a plurality of times without requiring destruction of retention structures. Desirably, the sides of a hard shell are structured and arranged in harmony with the energy distributing layer such that impact energy, generated by dropping the apparatus onto a flat surface, cannot be transferred to an electronic device contained inside the apparatus without first passing through the shell and a portion of the energy distributing layer.
A workable energy distributing layer comprises an elastomeric compound. An energy distributing layer can be formed from, or include, memory foam. The currently preferred energy distributing layer includes a two-pocket element, each such pocket being structured to engage a portion of an electronic device in direct contact therein. The two-pocket element is structured and arranged to be stretch-fit onto an electronic device during assembly of the protective enclosure. An energy distributing layer can include a first pocket configured to fit onto the top of an electronic device and a second pocket configured to fit onto the bottom of the electronic device. Such pockets may be discreet and separate elements. In general, an energy distributing layer can include a plurality of discrete sections of energy distributing material. Sometimes, a portion of an energy distributing layer is affixed to an inside surface of the hard shell.
Sometimes, a hard shell is structured in harmony with an energy distributing layer, an electronic device, and one or more membrane associated with one or more window, to permit placing the shell into a fluid-resistant configuration. In a preferred embodiment, a portion of an energy distributing layer is arranged as a door configured to cooperate with a first window in the hard shell to permit forming a dust-resistant seal there-between, a hinge of the door permitting rotation of the door in an outward direction through the first window. A membrane may sometimes be included to cover a second window in one of the sides of a hard shell to increase fluid and/or dust resistance. In certain cases, such a membrane is removable and replaceable. Certain embodiments may includes a gasket configured and arranged directly to form a water-resistant seal between a hard shell and enclosed electronic device. In one circumstance, a gasket is disposed around a perimeter of a display window of the hard shell such that a display window of the electronic device directly provides an area effective to resist fluid entry into the shell.
In the drawings, which illustrate what are currently regarded as the best modes for carrying out the invention, and in which like structure is generally indicated with like numerals:
The present invention provides an apparatus and method for increasing shock protection of a portable electronic device. A preferred embodiment forms an add-on external enclosure structured to increase ruggedness of a commercially available portable electronic device, such as a telephone.
As illustrated in
Enclosure 100 includes a cover 106, and a tub, generally 108. Illustrated tub 108 includes a top tub 110, and a bottom tub 112. Enclosure 100 may be characterized as defining a volume 114 disposed inside of a front side 116, back side 118, top side 120, bottom side 122, left side 124, and right side 126. A side may sometimes be made reference to alternatively as a wall, or a shell, or shell element. It is recognized that there may be a grey area of distinction between exact boundaries of such sides, e.g. due to rounded corners, but for purpose of this disclosure, even a round ball has the six sides set forth above.
It is preferred to include one or more window, aperture, or opening disposed in one or more side to permit operation of at least one control of an electronic device 104 when the electronic device 104 is contained inside a protective enclosure, such as enclosure 100. As illustrated, enclosure 100 includes window 128 to permit access to a touch-screen; aperture 130 to permit operation of a push-button; one or more opening 132 for microphone pick-up; button operation openings 134 and 136; power access port 138; speaker and camera opening 140; camera apertures 142 and 144; main I/O aperture 146; and headphones access port 148. Other workable embodiments of an enclosure may have more, or fewer, access ports, apertures, openings, or windows, and the like.
With continued reference to
It is currently most preferred that the layer 150 is configured to space the entirety of device 104 from contact to the shell 102, upon initial assembly. That is, it is desirable for the sides of a hard shell, such as shell 102, to be structured and arranged in harmony with an energy distributing layer 150 such that impact energy, generated by dropping the assembled device 100 onto a horizontal flat surface, cannot be transferred to an electronic device 104 contained inside hard shell 102 without first passing through a portion of the energy distributing layer 150. Of course, it is to be realized that, for purpose of the aforementioned test of dropping the device onto a flat surface, that flat surface necessarily is defined as a flat surface that is larger than can fit into a shell window or aperture, for example.
Still with reference to
In other instances, the energy distributing layer 150 may include one or more intermediary movable structure, such as flexible link element 154, which is configured for displacement by a user to operate one or more push-button of a device 104. Flexible link element 156 performs a similar function. Desirably, the exemplary flexible link elements 154 and 156 are integral parts of the wall of the liner 150, and therefore inherently resist entry of water, dust, and the like, through respective apertures 146 and 130 for contact with the electronic device 104.
Flexible link element 158 is structured as a hinged door that can be opened by a user to permit access through opening 146 in shell 102. In the illustrated embodiment, a hinge is formed by an edge of the door 158 being integral with the wall of liner 150. The hinge of door 158 permits the door 158 to open outwardly, extending through the aperture 146. Desirably, door 158 is configured either in harmony with the aperture 146 or a local portion of the liner 150 (in a closed position) to form a resistant barrier to water, dust, and the like through aperture 146 for contact with a device 104.
A currently preferred energy distributing layer 150 is formed from, or includes, an elastomeric compound. A workable elastomeric compound includes silicone, rubber, and the like. An alternative operable energy distributing layer 150 may be formed from, or include a portion of, memory foam. In certain embodiments, a portion of a workable energy distributing layer 150 may be biased in compression upon assembly of a shell 102 to enclose a device 104 within a liner 150. In other circumstances, one or more air gap may be provided between a hard shell and the enclosed electronic device and/or a portion of an energy-distributing liner.
With reference now to
An alternative energy distributing layer 150 within contemplation includes a plurality of discrete sections of energy distributing material. For example, first and second pockets 160, 164 may be separate elements, unconnected by an elastic coupling element. (One such autonomous pocket is illustrated by the structure shown in
With reference to
Still with reference to
Thickness, shock absorbing, dampening, cushioning, smooth distribution of point loads, load suspension, and energy dissipating capabilities or properties are important considerations and design trade-offs for an operable energy distributing layer 150. Beside silicone materials, foam which might have a durometer of as low as 20 may be used in certain embodiments. However, a silicone, or silicone-like, material having a Shore A durometer of between 40 and 90 is currently preferred for energy distributing layer 150. A currently preferred thickness for layer 150 is between about 0.01 and about 0.1 inches.
If the layer 150 is sufficiently compressible (e.g. foam having a Shore A value of about 20) layer 150 can be pre-loaded with a little compression (without worrying about resonance) which helps reduce overall layer thickness. If the durometer number is a little higher(say 40) a small air space between shell and layer 150 may be included, which gap acts as another suspension layer (and helps with assembly and manufacturing tolerances). The air gap bottoms out before the energy distributing layer engages with the hard shell, which can provide higher levels of protection like survivability from a higher drop. Also, the softness of a layer 150 is integral with the feel of the button and flex door features which also may drive the design depending on the size and placement of the device controls.
With particular reference to
As shown in
With reference to
With reference to
Similar to end capture structure 224, end capture structure 234 illustrated generally in
As perhaps illustrated best in
The push-button flex latch 202 illustrated best in
It should be noted that a cover 106 is not required to be embodied as a substantially flat plate. Alternative configurations are within contemplation for a cover 106, nonexclusively including placing a parting line at the midpoint of a pair of tub elements. In such case, one of the tub elements may be characterized as a cover, and the other may be characterized as the tub. In similar manner, a socket, ramp, lip, or end capture feature may be carried by either a cover, or a tub element. Further, an overlapping portion of a cantilevered rail or flange may be disposed inside with respect to a cooperating structure on one embodiment, and outside on another.
With reference now to
A resilient gasket 250 may be included in certain embodiments to assist in forming a fluid and/or dust resistant seal between a shell and either a layer 150 or device 104. As illustrated, gasket 250 is disposed around a perimeter of display window 128 such that a display window of electronic device 104 directly provides an area effective to resist water entry into shell 102.
In certain embodiments, a shell may be structured in harmony with an energy distributing layer, enclosed electronic device, and one or more membrane associated with one or more window to permit placing the shell into a water-resistant configuration. Aperture(s), access port(s), and window(s) may be covered with suitable water-resistant membrane barrier(s). In such case, water-resistant is distinguished over water-proof. It is recognized that a user can still potentially open an access door to defeat the water-resistant character of desirable embodiments.
Cantilevered flange 272 projects from an inside surface of cover 262 and skirts a portion of the perimeter edge of tub 264. As illustrated, flange 272 is arranged to overlap rim 270 at the joint between cover and tub. Between them, wall elements of flange 272 and rim 270 carry a plurality of cylinder-in-socket retention structures, generally 276. As illustrated in
Desirably, some sort of connection structure, such as a plurality of cylinder-in-socket structures, of the sort generally indicated at 276, are provided to permit a snap-together connection between tub 264 and cover 262 to form a uni-body enclosure that can be assembled and disassembled a plurality of times without requiring destruction of the retention structures.
The embodiment generally indicated at 290 in
A workable material for a hard shell, according to this disclosure, has a minimum flexural modulus of about 200,000 psi. This includes substantially all ABS (250K), Polycarbonate (345K), and ABS Polycarbonate blends, as well as metallic shells. The range for hard shell thickness is typically between about 40 and 100 mils. The inner liner thickness should generally fall within about 10 and 100 mils. Desirably, the combined thickness of the hard shell and energy-distributing liner is typically not more than about 170 mils. A very generalized design rule for preferred embodiments indicates thickness of the hard shell can vary inversely according to a formula including liner thickness, and directly with respect to shell stiffness.
Certain prior art telephone-protection devices include an exterior surface of silicone, which is generally also textured. That sort of surface can have a coefficient of friction greater than 1.0, and make it difficult to slide the device into a pocket. Desirably, a substantial portion of the exterior of an assembly, such as assembly 100, is configured to provide a coefficient of friction of less than about 0.3 to facilitate entry of the assembly 100 into a user's pocket. It is currently believed that a “substantial portion” can encompass about 85%, or more, of the exterior surface.
Preferably, exposed sides of the hard shell 102 are adapted to avoid friction with pocket material by exposing a low-friction material extending for at least about ⅔ total shell length from the bottom end. In this case, “exposed” may be defined to encompass only raised areas adjacent to a recessed insert that fingers could touch, but would not reasonably contact shirt pocket material when sliding a shell 102 into a pocket. For purpose of this disclosure, “low-friction material” may be defined as a material having a coefficient of static friction of less than about 0.3.
One way of estimating the strength of the protective enclosure, or hard shell, is to assume that the cross-section shape is similar to a regular geometric shape such as a rectangle, then apply a three-point bending setup to measure the flexural strength for that shape under load. The formula for such a system is s=3FL/2bd2, where s is flexural strength which is also related to stiffness or rigidity of the outer shell; F is a force applied at the middle of the unsupported span; b is the width of the outer shell; d is the depth or thickness of the outer shell; and where L is the distance between the 2 span supports.
The method of measuring flexural strength is to apply force F until the case integrity starts to fail. That failure can be significant flexing such as is seen with case styles that utilize clip-on hard shells over a soft liner. One such device flexed 20% of d with about 1-2 lbs of pressure. If L=4 in; b=2.5 in; and d=0.5 in, then s=approximately 12-24 psi. Table 1 sets forth actual test results for several commercially available telephone protection cases. As indicated in Table 1, embodiments structured according to certain principles of the invention are projected to carry 50 lbs of force translating to s=approximately 600 psi.
Note that the flexural strength could vary depending on the particular device dimensions, enclosure materials and hard shell wall thickness. A preferred embodiment has a hard shell structured to contain a telephone and to carry a minimum 3-point bending load in excess of about 25 pounds. The bending load is applied with two base points that are spaced apart on one side of the hard shell by 4 inches and the load is applied on the opposite side at the mid-span location.
Also, note that the jarring forces of various impacts can be unpredictable and that this bending test is believed to be the worst case test that certain embodiments of this invention can undergo because tension on the bottom latch is the weakest point. The push-button flex latch 202 is designed to have a double connection including the secondary retention socket 244, and positive camber to at least one connection surface, which will tend to keep the latch engaged during this type of loading. Tests with other orientations are expected to produce many times better results because almost all other impact forces will be with the direction of the connections and tend to reinforce the connection.
An additional advantage of the preferred hard shell construction and rigidity is the number of connection points (which is 11 in the current embodiment but is not limited to 11 and can be many more or even nearly continuous). Note that the latches of the hard shell of a leading commercially available enclosure protrude through the outer cushion layer defeating the ability of the cushion layer to absorb impacts. Preferred embodiments of the invention not only have the advantage of having the cushion layer suspended internally inside the hard shell, but the hard shell uniquely avoids protruding latch or connection points and has somewhat uniform wall thickness. A uniform skin without disruptions is stronger, it may also minimizes impact liabilities as well as potentially slimming the overall enclosure.
While the invention has been described in particular with reference to certain illustrated embodiments, such is not intended to limit the scope of the invention. The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
Claims
1. An add-on apparatus to increase ruggedness of a commercially available portable electronic device, the apparatus comprising:
- a hard shell configured in general agreement with the exterior of said electronic device and comprising enclosing sides including a front side, back side, top side, bottom side, left side, and right side, said sides being arranged to define a first volume, one or more window being disposed in one or more of said sides and configured to permit operation of at least one control of said electronic device when said electronic device is contained inside said shell; and
- an energy distributing layer structured for disposition inside said shell and defining a second volume in which to receive said electronic device, said energy distributing layer being arranged to space a portion of said electronic device apart from direct contact with said shell.
2. The apparatus according to claim 1, wherein:
- said sides are structured and arranged in harmony with said energy distributing layer such that impact energy, generated by dropping said apparatus onto a flat surface, cannot be transferred to an electronic device contained inside said apparatus without first passing through said shell and a portion of said energy distributing layer.
3. The apparatus according to claim 1, wherein:
- said shell comprises a plurality of elements that may be assembled to form a uni-body enclosure.
4. The apparatus according to claim 1, wherein:
- said shell comprises a tub and a cover;
- a perimeter edge of said tub comprises a shelf and a cantilevered rim, said rim being adapted to overlap structure of said cover at a joint there-between;
- a cantilevered flange projects from an inside surface of said cover and skirts a portion of said perimeter edge of said cover, said flange being arranged to overlap said rim at said joint; and
- wall elements of said flange and said rim carry a plurality of cylinder-in-socket retention structures, said retention structures being configured to effect a snap-together connection between said tub and said cover to form a uni-body enclosure that can be assembled and disassembled a plurality of times without requiring destruction of said retention structures.
5. The apparatus according to claim 1, wherein:
- said shell comprises a cover, a top tub, and a bottom tub;
- a slide rail system is formed in combination between said cover, said top tub, and said bottom tub, said slide rail system being configured to permit slide-assembly of each said tub onto said cover;
- a push-button flex latch is carried by one said tub and is configured and arranged to removably couple said top tub to said bottom tub when said top tub and said bottom tub are in an assembled location on said cover; and
- a relief area is formed in said energy distributing element and is arranged to permit a user to impart a transverse deflection to said latch to permit separation of a said tub from said cover.
6. The apparatus according to claim 5, wherein:
- a detent-and-ramp structure associated with said slide rail system is configured and arranged to resist sliding a said tub from an installed position.
7. The apparatus according to claim 1, wherein:
- said energy distributing layer comprises an elastomeric compound.
8. The apparatus according to claim 1, wherein:
- said energy distributing layer comprises memory foam, and a portion of said energy distributing layer is biased in compression upon assembly of said shell.
9. The apparatus according to claim 1, wherein:
- said energy distributing layer comprises a two-pocket element, each said pocket being structured to engage a portion of said electronic device in direct contact therein.
10. The apparatus according to claim 1, wherein:
- said two-pocket element is structured and arranged to be stretch-fit onto said electronic device during assembly of said apparatus.
11. The apparatus according to claim 1, wherein:
- said energy distributing layer comprises a first pocket configured to fit onto the top of said electronic device and a second pocket configured to fit onto the bottom of said electronic device.
12. The apparatus according to claim 1, wherein:
- said energy distributing layer comprises a plurality of discrete sections of energy distributing material.
13. The apparatus according to claim 1, wherein:
- a portion of said energy distributing layer is affixed to an inside surface of said shell.
14. The apparatus according to claim 1, wherein:
- a portion of said energy distributing layer is arranged as a door configured to cooperate with a first window in said shell to permit forming a dust-resistant seal there-between, a hinge of said door permitting rotation of said door in an outward direction through said first window.
15. The apparatus according to claim 14, further comprising:
- a membrane disposable to cover a second window in one of said sides.
16. The apparatus according to claim 15, wherein:
- said membrane is removable and replaceable.
17. The apparatus according to claim 1, further comprising:
- a gasket configured and arranged to form a water-resistant seal, between said shell and said electronic device, around a perimeter of a display window of said shell such that a display window of said electronic device directly provides an area effective to resist water entry into said shell.
18. The apparatus according to claim 1, wherein:
- said shell is structured in harmony with said energy distributing layer, said electronic device, and one or more membrane associated with one or more window to permit placing said shell into a fluid-resistant configuration.
19. The apparatus according to claim 1, wherein:
- said shell is structured to contain a telephone and to carry a minimum 3-point load in excess of about 25 pounds, wherein:
- two base points are spaced apart on one side of said shell by 4 inches and the load is applied on the opposite side at the mid-span location.
20. An apparatus, comprising:
- a hard shell arranged to define a first volume, one or more window being disposed in said shell and configured to permit operation of at least one control of an electronic device when said electronic device is contained inside said shell;
- an energy distributing layer structured for disposition inside said shell and defining a second volume in which to receive said electronic device, said energy distributing layer being arranged to space said electronic device apart from direct contact with said shell; and
- a portion of said energy distributing layer being arranged as a door configured to cooperate with a first window in said shell to permit forming a dust-resistant seal there-between, a hinge of said door permitting rotation of said door in an outward direction through said first window.
Type: Application
Filed: May 2, 2012
Publication Date: Nov 7, 2013
Inventor: W. Paul Willes (Alpine, UT)
Application Number: 13/461,951
International Classification: B65D 81/02 (20060101);