United States Patent tº
`
`Szekely et al.
`
`-
`
`[54]
`
`[75]
`
`SOLAR CELL PACKAGING ASSEMBLY FOR
`SELF-CONTAINED LIGHT
`
`Inventors: Klara Szekely, West Hills; Bethanne
`Felder; Lloyd V. Wallace, both of
`Thousand Oaks, all of Calif.
`
`[73]
`
`Assignee: Siemens Solar Industries, L.P.,
`Camarillo, Calif.
`
`[21]
`
`Appl. No.: 392,502
`
`[22]
`
`Filed:
`
`Aug. 11, 1989
`
`[51]
`[52]
`[58]
`
`Int. Cl* ........................................... H01L 31/048
`U.S. Cl. .................................... 136/251; 136/259;
`136/291; 362/183
`Field of Search ....................... 136/251, 259, 291;
`362/183
`
`[11] Patent Number:
`[45] Date of Patent:
`
`4,999,060
`Mar. 12, 1991
`
`
`
`[56]
`
`References Cited
`U.S. PATENT DOCUMENTS
`4,057,439 11/1977 Lindmayer .......................... 136/251
`4,241,493 12/1980 Andrulitis et al. ...................... 437/2
`4,280,853 7/1981 Palazzetti et al. ...
`... 136/246
`4,321,417 3/1982 Kurth et al. ........................ 136/246
`Primary Examiner—Aaron Weisstuch
`Attorney, Agent, or Firm—Nilsson, Robbins Dalgarn,
`Berliner Carson & Wurst
`[57]
`ABSTRACT
`A self-contained photovoltaic powered light which is a
`stand alone unit. The solar cells which power the light
`are assembled and maintained within the top, or upper,
`portion of the self-contained unit. The solar cells are
`encapsulated within a resiliently deformable material to
`provide for contraction and expansion of the solar cells
`while at the same time providing protection from the
`elements for the assembly.
`
`5 Claims, 3 Drawing Sheets
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`Yotrio Ex. YOT-1011, Page 1
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`U.S. Patent
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`Mar. 12, 1991
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`Sheet 1 of 3
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`4,999,060
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`Yotrio Ex. YOT-1011, Page 2
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`

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`U.S. Patent
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`Mar. 12, 1991
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`Sheet 2 of 3
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`4,999,060
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`/42
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`/36
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`Yotrio Ex. YOT-1011, Page 3
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`U.S. Patent
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`Mar. 12, 1991
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`Sheet 3 of 3
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`4,999,060
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`/64
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`/88
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`Yotrio Ex. YOT-1011, Page 4
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`4,999,060
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`SOLAR CELL PACKAGING ASSEMBLY FOR
`SELF-CONTAINED LIGHT
`
`BACKGROUND OF THE INVENTION
`
`This invention relates generally to lighting devices
`and more particularly to a self-contained photovoltaic
`powered light. More specifically, the invention is di-
`rected to a packaging assembly for the solar cells.
`In the prior art, there exists many electrically pow-
`ered outdoor lighting systems which are utilized to
`illuminate pathways, yards, certain areas of parks, or
`other predetermined areas. Typically such lights are
`connected to the public utility system, or similar source
`of electrical power and are controlled by preset timing
`devices so that they illuminate at nightfall and extin-
`guish at a predetermined time, such as approaching
`daybreak, or the like. Such lights require extensive
`cabling, including conduits as well as appropriate tim-
`ing mechanisms and are thus relatively expensive to
`install and maintain. In addition thereto, by utilizing
`electric power generated in the traditional manners,
`such as by the burning of fossil fuels, additional contam-
`ination of the environment occurs as well as depletion
`of fossil fuel sources. Therefore, there is a need to pro-
`vide a source of illumination for predetermined outdoor
`areas which does not require connection to a public
`utility source of power or the like and which is rela-
`tively easy and inexpensive to install and requires no
`maintenance.
`
`SUMMARY OF THE INVENTION
`
`A solar packaging assembly including a tray having a
`floor and a side wall. A plurality of electrically inter-
`connected solar cells are disposed within the tray. The
`solar cells are surrounded by an optically clear, resil-
`iently deformable material supported upon the floor of
`the tray and retained within the side walls thereof.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a perspective view illustrative of a light
`constructed in accordance with the principles of the
`present invention;
`FIG. 2 is an exploded view showing the various com-
`ponent parts of the structure as illustrated in FIG. 1;
`FIG. 3 is a cross-sectional View of the bezel taken
`about the lines 3-3 of FIG. 2;
`FIG. 4 is a cross-sectional view of the cover taken
`about the lines 4-4 of FIG. 2;
`FIG. 5 is a top plan view illustrating the encapsula-
`tion of the solar cells; and
`FIG. 6 is a cross-sectional view of the solar cell en-
`capsulation taken about the lines 6-6 of FIG. 5.
`
`DETAILED DESCRIPTION
`
`The self-contained lamp 10 is illustrated in FIG. 1 and
`is a stand alone lamp which includes a self-contained
`electrical power source such as a battery which is main-
`tained in a charged condition by a solar cell array and
`includes an electrical circuit which controls application
`of electrical power to an electric light bulb contained
`therein. The electrical power from the battery is sup-
`plied to the light bulb when the solar cell array is not
`producing electricity, that is, when the ambient light
`falls below a predetermined level. The lamp 10 includes
`top portion 12 having a lens 14 affixed thereto. A stake
`16 is,
`in turn, attached to the lens 14 and is used to
`position the lamp 10 in the desired area such, for exam-
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`ple, as by inserting the stake 16 into the earth. A solar
`cell assembly 18 is retained within the top portion 12
`while decorative disks 20 are retained upon the lens 14.
`The entire lamp assembly 10, as illustrated in FIG. 1,
`may be moved from place to place and positioned at any
`particular point which may be desired for any particular
`application. For example, a plurality of the lamps 10
`may be positioned to illuminate a pathway as well as to
`delineate the same. In addition, such a plurality of lamps
`10 may be placed to illuminate a given area during
`nighttime hours.
`By reference to FIG. 2, a more detailed understand-
`ing of the structure of the lamp 10 may be obtained. The
`upper portion 12 of the lamp includes-a bezel 22 which
`is preferably constructed of a molded plastic, such as
`ASA (acrylic styrene acrylonitrile) or the like, which is
`sturdy yet somewhat flexible for the purposes to be
`described below.
`The bezel 22 defines an inner surface 24 from which
`there inwardly extends a plurality of spaced apart latch-
`ing ribs as shown at 26 and 28. Similar ribs, such as those
`illustrated at 26 and 28, are angularly disposed about the
`inner surface 24 of the bezel 22. Preferably, the latching
`ribs are disposed at 90° intervals about the surface 24;
`however,
`they may be disposed at different angular
`positions such as 120° or 60° depending upon the num-
`ber desired. Also inwardly directed from the surface 24
`are a plurality of snap lock retainers as shown at 30.
`Again, such snap lock retainers are angularly disposed
`about
`the surface 24 and preferably at 90° intervals
`although other intervals may be utilized as desired.
`The bezel 22 also defines an upper opening 32 within
`which the solar cell array is disposed to receive the
`sunlight during daylight hours to charge the battery
`contained within the light. The details of construction
`of the bezel 22 may be better understood by reference to
`FIG. 3 which more clearly shows the position and rela-
`tionships of the latching ribs and the snap lock retainer.
`As is therein shown, additional latching ribs 34, 36, 38
`and 40 are shown extending inwardly from the inner
`surface 24 of the bezel 22. Additional snap lock retainers
`42 and 44 are also illustrated. As is more clearly shown
`in FIG. 3, the snap lock retainer 30 is displaced down-
`wardly from the edge 46 of the bezel which defines the
`opening 32. As will be described more fully hereinafter,
`such spacing permits the solar cell assembly 18 to be
`snapped into place within the bezel 22 and securely held
`there.
`
`By reference, again, to FIG. 2 and also to FIG. 4,
`there is illustrated a cover which fits over the solar cells
`and which forms a part of the solar cell assembly. The
`cover 50 is optically clear and is preferably constructed
`of a polycarbonate plastic material which is impact
`resistant. The polycarbonate material thus protects the
`solar cells from incidental contact and also from dust.
`As is shown, the cover 50, at its outer rim 52, includes
`a plurality of lugs as shown at 54, S6 and 58. Each of the
`lugs includes spaced apart protrusions as shown at 60
`and 62 with respect to the lug 56. Again, the lugs are
`angularly disposed about the cover 50 and preferably at
`90° spacing to match the spacing of the snap lock retain-
`ers 30 formed on the bezel 22. The protrusions 60 and
`62, when the cap 50 is positioned in place within the
`bezel 22, are spaced one on each side of a snap lock
`tongue formed on the solar cell assembly such, for ex-
`ample, as shown at 68 and to be described more fully
`below. As is more clearly shown in FIG. 4, the protru-
`
`Yotrio Ex._YOT-101 1, Page 5
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`Yotrio Ex. YOT-1011, Page 5
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`sions 64 and 66 extend bekow the lower rim 70 of the cap
`openings as illustrated at 140 and 142. Similarly, the tip
`50. Further protrusions are shown at 72 and 74 and are
`144 may be inserted into the bottom of the body portion
`those associated with the lugs 54 and 58 respectively.
`136 and secured in place by a screw positioned within
`The general curvature of the cap 50 is also further and
`the opening 146. The entire assembly is then inserted
`better illustrated in FIG. 4. As is also shown in FIG. 4,
`over the protrusion 148 provided at the bottom of the .
`the cap 50 includes a step 76 in the periphery thereof.
`lens 14 and held in place by a screw inserted through
`The step 76 fits within the opening 32 and conforms to
`the opening 150 in the body portion 134 of the stake 16.
`the upper edge 46 of the bezel 22. The step 76 termi
`Obviously, if such is desired to cause the lamp 10 to
`nates in a ledge 78 which Snugly mates against the upper
`extend a lesser distance from the surface, the coupling
`portion 80 of the inner surface 24 of the bezel 22. Such
`138 and the body portion 136 may be discarded.
`fit provides a seal against the entry of moisture into the
`As is illustrated more fully in FIGS. 5 and 6, the solar
`solar cell assembly.
`cell assembly 82 includes a tray 160 having a floor 162
`The solar cell assembly 82, along with the cap 50, are
`and an upstanding wall 164. Protruding upwardly from
`assembled together and snapped into the bezel 22. Addi
`the floor 162 is a plurality of stand-offs, such as shown
`tional locking tongues 84 and 86 displaced 90° from the
`at 166, 168, 170 and 172. The stand-offs 166 through 172
`15
`tongue 68 are illustrated and an additional locking
`take the form of a plurality of bumps which are spaced
`tongue, not shown, is disposed 180° from the tongue 68.
`apart on the floor 162. Any number of stand-offs may be
`As with the other protrusions, extension ribs and the
`utilized as desired so as to space the solar cells 174 away
`like, the angular displacement of the locking tongues
`from the floor 162 of the tray 160. Subsequent to appro
`may be any desired. In any event, the displacement is
`priate positioning of the solar cells 174 upon the stand
`such that the locking tongues on the solar cell assembly
`offs, as is illustrated particularly in FIGS. 5 and 6, a
`82 mate with the snap lock retainers 30, 42 and 44 on the
`potting compound 176 is poured into the tray 160
`inner surface 24 of the bezel 22. For assembly, the cap
`within the wall 164 so as to cover and surround the
`50 is placed so that the protrusions 56 and 60 fall outside
`solar cells 174. The potting compound 176 extends pref
`the tongues 68, thus securely and snugly fitting the cap
`erably up to the upper edge 178 of the wall 164 and thus
`over the solar cell assembly 82. The combination is then
`completely covers the upper surface of the solar cells
`inserted into the bezel 22 and the locking tongues 68, 84
`174. The potting compound 176 is preferably silicone
`and 86 are snapped into place in the space provided
`which is optically clear and is in its cured state resil
`between the upper edge 46 and the snap lock retainers
`iently deformable.
`30, 42 and 44. The ability to snap the combination of the
`After the potting compound has been poured in
`30
`cover 50 and the solar cell assembly into place is pro
`place, it is heated along with the tray and the solar cells
`vided by the flexibility of the molded plastic forming
`in an oven at between 80° C. and 90° C. for approxi
`the bezel 22. A more detailed explanation of the encap
`mately 2 hours to cause it to cure and set. The potting
`sulation of the solar cells to form the solar cell assembly
`compound 176 is also ultraviolet inhibited so that it does
`82 will be provided below.
`not turn color when exposed to the sun. The resiliently
`A component tray assembly 90 is provided to receive
`deformability of the potting compound 176 is important
`a battery 92 and electrical circuit assembly 94 and light
`to the present invention. Such resilient deformability
`bulb (not shown) in a central aperture 96. The tray 90 is
`allows expansion and contraction of the solar cells 174
`interconnected by electrical wires 98 and 100 to the
`without subjecting them to cracking, thus providing a
`solar cell assembly 82 so that electrical power may be
`long life for the lamp. Appropriate electrical leads, one
`provided from the solar cells to the battery 92 to main
`of which is shown at 98, extends through an opening
`tain the same in a charged condition. The battery also,
`provided in the floor 162 of the tray 160 to provide the
`through the provision of the circuit assembly provides
`electrical power as above described.
`electrical power to the light when the solar cells are not
`By particular reference to FIG. 6, it may be seen that
`generating electrical energy. The component tray as
`the tray 160 includes an outwardly extending peripheral
`45
`sembly 90 includes notches 102, 104, 106 and 108 which
`rim 180 which extends outwardly from the wall 164.
`are used to locate the component tray assembly 90
`Through the utilization of the rim 180 along with the
`within the space between the spaced apart locking ribs
`step 76 and ledge 78 there is provided an additional seal
`26, 28, 34, 36, 38 and 40. The tray may then be rotated
`for the solar cells which precludes moisture from con
`and secured in position at the bottom portion of the
`tacting the upper surface thereof. Such occurs through
`bezel 22. The lower surface of the component tray
`the mating of the cap 50. The lower rim 182 thereof
`assembly 90 then closes the bottom of the bezel 22 to
`seats upon the ledge 184 formed by the rim 180 while
`provide a completed assembly.
`the inner surface 186 of the cap 50 mates with the verti
`The lens 14 includes outwardly extending latching
`cal surface 188 of the wall 164. Through these mating
`fingers 110, 112, 114 and 116. Such fingers are inserted
`surfaces, it will be appreciated that for moisture to enter
`within openings as shown at 118 and 120 and the lens is
`and accumulate on the upper surface of the potting
`rotated appropriately to latch the same in place so as to
`compound 176, and thus over the surface of the solar
`extend downwardly from the component tray assembly
`cells, it must enter by traveling sideways between the
`90. The disks 20 are assembled upon the outer surface of
`surfaces 184 and 182 of the tray and cap and then up
`the lens 14 by slipping the openings as illustrated at 118
`wardly along the surfaces 186 and 188 of the cap and
`60
`and 120 over outwardly extending sectors 122 and 124
`tray. It has been observed that such a tortuous path
`and then rotating the disks so that they occupy the
`effectively eliminates the travel of the moisture into the
`space between the sectors 122 and 124 and the stops 126
`interior portion of the solar cell assembly. As will be
`and 128 associated with the sector 122 and the stops 130
`noted particularly with respect to FIG. 5, the solar cell
`and 132 associated with the sector 124.
`assembly also defines a plurality of openings 190, 192,
`65
`The stake 16 is assembled by inserting the body por
`194 and 196 so that the interior of the assembly may be
`tions 134 and 136 over the central coupling 138 and
`vented to the exterior, thereby precluding moisture
`securing the same by the use of screws inserted into the
`condensation within the solar cell assembly.
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`4,999,060
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`It will be appreciated by those skilled in the art that
`being resiliently deformable to permit said cells to
`the solar cells utilized in the solar cell assembly 174 may
`expand and contract without damage; and
`be any as desired and well known to those skilled in the
`a transparent cover over said solar cells, said cover
`being received by said tray at mutually contacting
`art. The manufacture of such cells is well known and
`will not be described herein. Such cells are readily
`surfaces, said contacting surfaces between said tray
`available on the open market from a variety of sources.
`and said cover defining a first horizontal plane and
`Preferably those used with the present structure are
`a second vertical plane orthogonally adjoining
`formed from single crystal silicon appropriately treated
`each other, said horizontal plane being disposed
`to provide a photovoltaic cell. Although the present
`below said vertical plane, thereby substantially
`invention has been described in conjunction with a
`excluding the entry of moisture by providing a
`pathway light which is essentially cylindrical in shape,
`tortuous path for the entry of moisture into said
`it will be understood and recognized by those skilled in
`assembly.
`the art that the particular geometric configuration of
`2. A solar cell packaging assembly as defined in claim
`the solar cell packaging assembly may take any form
`1 which further includes a bezel having an inner Sur
`desired for the particular application. The packaging
`face, a plurality of snap lock retainers extending in
`assembly will, in each instance, include the optically
`wardly from said inner surface and angularly disposed
`clear silicone potting compound which provides the
`thereabout, said tray and cover being retained within
`resiliently deformable encapsulation for the solar cells
`said bezel by said snap lock retainers.
`to permit expansion and contraction thereof. In addi
`3. A solar cell packaging assembly as defined in claim
`tion, the tray and cap will, in each instance, provide the
`2 wherein said tray includes a plurality of outwardly
`20
`mating surfaces therebetween so as to provide the tortu
`extending protrusions at the periphery thereof, each of
`ous path through which moisture must travel to enter
`said protrusions being received within a snap lock re
`the solar cell packaging assembly.
`tainer to secure said tray within said bezel.
`There has thus been disclosed a self-contained solar
`4. The solar cell packaging assembly as defined in
`powered lamp which may be utilized to eliminate or
`claim 3 wherein said tray defines openings extending
`delineate any particular area desired.
`therethrough to provide circulation with the ambient to
`We claim:
`preclude condensation of moisture internally of said
`1. A Solar cell packaging assembly comprising:
`assembly.
`a tray including a floor and a side wall;
`5. The solar cell packaging assembly as defined in
`a plurality of electrically interconnected solar cells
`claim 4 wherein said tray includes means for electrically
`disposed within said tray;
`contacting said solar cells and to convey electrical en
`an optically clear material substantially surrounding
`ergy generated by said solar cells through said tray for
`said solar cells and contained within said sidewall
`use in energizing electrical energy utilizing means.
`to secure said cells within said tray, said material
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