A light-control assembly including a modular beam with a plurality of adjacent circular bores separated by web portions, at least two bearing members each having an annular ring dimensioned to fit within the bores with non-interfering flanges extending radially outwardly from the rings mounted in the bores, and a series of light-controlling members mounted in the bearing members.

FIELD OF THE INVENTION

This invention pertains to a readily constructed light-control assembly designed for reliable light-blocking that is particularly effective in dynamic control of daylighting and shading. In the light-control assembly opaque or translucent slats or other light-blocking members are rotated up to 360° by applying rotary force at a single end of each of the light-blocking members, and less preferably at both ends thereof. The assembly achieves unusually effective light-blocking through the use of a beam having circular bores with bearing members associated with the bores that have offset flanges or other engagement means to ensure accurate positioning and reliable operation of the bearing members over a range of 360° rotation of light-blocking members mounted in the bearing members. The bearing members are coupled to the beam with offset positioning of the flanges or other engagement means making it possible to closely fit abutting edges of the light-blocking members by overlapping the web portions between adjacent bores in the beam to achieve enhanced, uniform light-blocking.

BACKGROUND OF THE INVENTION

The U.S. Department of Energy as well as sustainable construction organizations and the like are pressing for the installation of dynamic daylighting and shading systems to improve energy efficiency in buildings. Innovations like that of the present invention are sorely needed to meet this need.

Various types of transparent and translucent glazing systems are available for the construction of horizontal, vertical and sloped glazing in skylights, roofs, walls, and other architectural structures designed to pass light for daylighting interiors or other purposes. When using such glazing systems, it is therefore desirable, in accord with sustainable construction criteria, to optimize the system's shading coefficient to reduce solar heat gain on hot summer days and during peak sunlight hours year round, while providing maximum light and solar heating on cold winter days and when it is otherwise needed or desired. It is also often desirable to control glare and direct sunlight in order to ensure the comfort of those who occupy the space exposed to the glazing system. If architects and space planners can be freed from the constraints of current light transmission control in horizontal, vertical and sloped glazing in skylights, roofs, walls, and other architectural structures, they will be able to more effectively address these shading requirements and meet sustainable construction criteria. Furthermore, these considerations apply as well to shading of open unglazed areas.

Indeed, if the level of light entering overhead large glazed as well as unglazed areas can be simply, efficiently, effectively and uniformly controlled without significant light leakage between, e.g., multiple adjacent light-controlling members, it will further enable architects and space planners maximize energy efficiency with aesthetic and sustainable designs. However, this requires light-controlling assemblies and sun control systems that can be dynamically controlled. For example, sun tracking control shading systems that can dynamically rotate light-locking members up to 360° to shade small or large glazed and open, unglazed areas to provide the desired uniform light level inside the space thereunder would be particularly desirable.

The known approaches to controlling the amount of light admitted through glazing systems—particularly on a large scale and in overhead, horizontal and sloped glazing applications—are limited and are generally unreliable, noisy and often difficult and expensive to construct, assemble on-site, maintain and service. Also, existing approaches suffer from non-uniform and excessive light leakage between adjacent light-controlling members which appears as an aesthetically undesirable series of often irregular bright lines. Additionally, although it is often desirable to retrofit light-controlling systems to already constructed glazing systems, this is not easily accomplished with any of the current light-controlling systems. There is therefore a substantial need for an economic and readily constructed and retrofitted light-controlling system that may be used for shading glazed areas of all sizes, including very large glazed areas. There is also substantial need for such light-controlling systems that can be easily assembled, maintained and serviced, in which the light is uniformly distributed across the glazed area, and in which light leakage is de minimis or eliminated and, where present, is kept to narrow and regular lines.

Prior approaches to controlling the level of light passing into architectural structures have included louver blind assemblies using pivoting flexible light-controlling members operable behind a window or sandwiched inside a chamber formed by a double-glazed window unit. Such louver blinds require substantial support of the flexible members which, additionally, must be controlled from both their distal and their proximal ends. Furthermore, louver blinds are difficult and expensive to assemble, apply, operate, maintain and replace, and cannot be readily adapted for use in non-vertical applications or in applications in which it is either desirable or necessary to control the flexible members from only one end. Louver blinds are particularly problematic when it comes to applications in which the installation requiring light-control or shading is very long, e.g., 10 ft., 20 ft., 60 ft. or more. In addition, dynamic control of louver blinds in large overhead shading applications is complicated, expensive, difficult to install and maintain, and often simply impractical. Furthermore, rotating louver blinds requires that the rotary force be applied to the top edge of the blinds. This is because louver blinds are flexible and rely on the force of gravity to hang vertically in the proper desired position and therefore cannot be rotated from their base. Thus, louver blinds cannot be used in generally horizontal overhead glazing application or in sloped applications, where rotation must be controlled from the base or proximal end and the force of gravity on non-vertical louver blinds would create untold complications and very non-uniform shading.

Other approaches to controlling the level of light passing through architectural structures have used motorized shades or drapery. These approaches are also problematic, particularly in the applications noted above where the glazing is large and would require lengthy shades or blinds, e.g., on the order of 10 ft., 20 ft., 60 ft. or more, since such large shades would be heavy, difficult to manipulate and maintain, and expensive. The mechanics of controlling and manipulating motorized shades or drapery of any size is quite complicated and therefore motorized shades and drapery are expensive and difficult to maintain. Also, it is not possible to achieve uniform light distribution across a wide glazed space with motorized shades or drapery.

U.S. Pat. Nos. 7,281,353; 6,499,255; and 6,978,578 provide other more recent approaches to addressing the challenge of providing dynamic daylighting and shading systems on a large scale and in overhead, horizontal and sloped glazing applications. These patents utilize a plurality of rotatably-mounted light-blocking tubular members having at least one portion that is substantially opaque and means for rotating the light-blocking members to block out varying amounts of radiation by varying the area of the opaque portions presented to the incoming light. In the systems described in the above three patents, the light-blocking members are combined in a series of adjacent segregated elongated tubular cells or mounted for rotation in individual or paired cross-members positioned between light transmitting panels. As an alternative to tubular members, a generally rigid opaque member may be used if fitted with rings spaced along this member. Indeed, even the tubular members may be fitted with such rings in order to facilitate tubular member rotation and to improve performance. Attachment of the rings requires notching of the generally rigid opaque member and is difficult and time consuming for both generally flat and tubular members. Also, the rings interfere with light-blocking and must be wide enough to accommodate longitudinal movement due to thermal expansion and contraction. Thus, determining the width and location of the rings and receiving notches is complex and, indeed, may require architectural approval before being implemented in custom applications, often making the use of such rings inconvenient and expensive.

In the system of the '578 patent, the centers of rotation of the light-blocking members do not remain in place as the light-blocking members are rotated resulting in increased torque and load on the motor and varying horizontal positioning of the light-controlling members. Since the light-controlling members often do not run true because they are inadequately restrained and therefore bend and snake about as they rotate, uneven and continuously varying spacing between adjacent members is produced with uneven light distribution and an unacceptable appearance of disarray of the radiation blocking members. When these light-controlling members are used in vertically oriented applications, the light-blocking members disengage from lower-cross-members and run far more untrue with even greater increases in the torque/motor load and irregular lateral movement. When they are used in applications calling for an inclined orientation, the light-blocking members tend to disengage from the lower cross members and rotate in an uncontrolled manner, rubbing against one another, resulting in increased friction and torque and producing problematic noise. Finally, in tests simulating the application of snow and wind loads, excessive friction is produced between the light-blocking members and the cross-members which could cause early failure.

The paired upper and lower cross members of the '353 patent solve the above problems. However, even this dual cross member design has drawbacks where rings and notching are used. Also, when this system is in the fully closed position, there is still more light leakage than is often desired.

While the designs provided by the above three patents nevertheless represent important advances in the art, they have another serious drawback. For these designs, the light-blocking components of adjacent tubular members cannot come sufficiently close to each other when the systems are in their fully closed configuration due to intervening structural features including the material between adjacent tubular cells in the '255 patent and the tube and ring walls in the designs of the '578 and '353 patents. Therefore total blackout or near total blackout light blocking cannot be achieved.

SUMMARY

It is therefore one objective of this invention to provide a light-control assembly in which the transmission of light can be adjusted from almost full transparency or passage of light to total black-out or near total black-out.

It is another objective of the present invention to provide a light-control assembly that is reliable, quiet in operation, and readily constructed, maintained and serviced.

It is yet another objective of the present invention to provide a light-control assembly that may be readily assembled on-site and that can be used in both new construction and retrofit applications.

It is still a further objective of the present invention to provide a light-control assembly that accommodates thermal expansion and contraction of the components of the assembly, including the light-controlling members, when the assembly is subjected to wide-ranging temperature changes at the site of installation so that, e.g., slats in the assembly can move longitudinally within bearing members free from limitations imposed by rings and notches as the slats lengthen or shorten due to temperature swings.

Still another objective of the present invention is to provide a light-control assembly that may be readily used with horizontal, vertical and sloped glazing in skylights, roofs, walls and other glazed and open unglazed architectural structures designed to pass light for daylighting interiors or other purposes.

Another objective of the present invention is to provide a light-control assembly that can be readily serviced on-site.

Yet another objective of the invention is to provide light-control assemblies that can be spaced along any desired length of adjoining long light-blocking members to accommodate rotation of the light-blocking members up to 360° by applying a rotary force about their longitudinal axes at only one end of the light-blocking members.

A still further objective of the invention is to provide a light-control assembly that can simply and efficiently be used with photovoltaic members.

Another objective of the invention is to provide light-control assemblies that can be made of modular components so larger assemblies can be economically and readily constructed and used in dynamic control of daylighting and shading in applications of varying widths.

A still further objective of the present invention is to provide a light-control assembly that can accommodate radius bends in light-blocking members and that will continue to operate reliably in such installations.

It is still another objective of the present invention to provide a light-control assembly with light-controlling members that are free of notching and/or rings or other structurally weakening material removal and can be easily and simply slid into position.

It is a further objective of this invention to provide efficient, economic means for supporting and maintaining light-controlling members in panel units having spaced flat panels or sheets in ways not heretofore thought possible.

These and other objectives of the present invention will become apparent to those skilled in the art upon consideration of the accompanying specification, claims and drawings.

DETAILED DESCRIPTION OF THE INVENTION

The embodiments of the invention described in detail below are not intended to be exhaustive or to limit the invention claimed to the precise structures and operations disclosed. Rather, these embodiments have been chosen and described to highlight selected principles of the invention and its application, operation and use in order to best enable those skilled in the art and others to follow its teachings.

Turning now toFIG. 1, a light-control assembly10is illustrated. Assembly10includes first and second opposed faces14and16first and second ends15and17, and a series of adjacent circular bores18extending between the opposed faces of the assembly and exemplary bearing members30shown mounted in two adjacent bores18aand18b. Bores18are formed in the beam70(FIG. 4A) of the assembly which will be described below. The longitudinal axes22of the bores preferably will be generally parallel to each other although they need not be generally parallel in all embodiments of the invention.

Adjacent circular bores18are separated by a web portion20(FIGS. 1 and 1A) of beam70(FIG. 4A) defined by the lateral spacing of the bores. Web portion20will be shaped as indicated inFIG. 1Awith its thinnest dimension “A” at the point where the diameters of the adjacent bores that define the web are co-linear.

It is preferred that web portion20be as thin as possible in order to optimize the light-blocking performance of the light-control assembly by minimizing the distance between the adjacent edges of the light-controlling members when they are in the closed position, as will be described in more detail below in connection withFIGS. 6C and 6F. Of course, web portion20must not be so thin as to adversely affect the structural integrity of the beam. Thus, the thickness of thinnest dimension “A” at the point where the diameters of the adjacent bores that define the web are co-linear will depend on the material out of which beam70is made as well as the thickness of the beam between its opposed forces and other structural features of the beam and other structural components of the light-control assembly. In one embodiment, where the beam is made out of polycarbonate, the bores are about 45 mm in diameter and the thickness between the opposed faces of the beam is about 16 mm, the web should be no thinner than about 1 mm.

Light-control assembly10includes exemplary bearing members30as shown inFIG. 1and as illustrated in enlarged form inFIGS. 2A and 2B. In this embodiment, bearing members30each include an annular ring32dimensioned to fit rotatably within bores18and a retention flange34extending radially outwardly from the rings. The width of flange34should be less than or equal to the thickness of web portion20between the bores to preclude interference between the flange and light-blocking members mounted in bearings in the adjacent bores.

Bearing members30have at least two diametrically opposed notches36aand36b. Notches36aand36bhave opposed notch bottoms38aand38bspaced a predetermined distance apart “B”. In the embodiment of these figures, notches36aand36bextend through the rings and into the flanges leaving web portions of the flange40aand40bbelow the bottom of each of the notches. In this illustrated embodiment bearing members30also include an optional second pair of diametrically opposed notches36cand36dequally spaced from notches36aand36bto help maintain the circularity of the bearing members when they are made by a plastic injection molding process.

The bearing members in this embodiment also include pairs of guide and retention tabs42aand42blocated on opposite edges of the notches. Tabs42aand42bproject from the inner surface44of the ring to define a “V” shaped receiving cavity that opens towards the center of the bearing member.

Notches36aand36b(optionally including retention tabs42aand42a) are designed to receive light-blocking members in the form, for example, of slats150, which are described below in connection with the description ofFIGS. 6A-6Eand which themselves act as opaque reflecting, spectral controlling or translucent barriers. Notches36aand36b, of course, can receive other types of light-blocking members that act as opaque, translucent, reflecting or spectral controlling barriers including without limitation flat light-blocking members, light-blocking members300a-300kofFIG. 11, tubular designs light-blocking members300l-300oofFIG. 11and the tubular hemispherical light-controlling members fitted with opaque or translucent barriers, as described below. The shapes shown inFIG. 11employ the principle of retro-reflection as disclosed in US 2006/028845A1, the pertinent disclosure of which is incorporated by reference. Finally, as illustrated inFIG. 12, micro-prismatic toothing302may be provided on the surface304of a light-blocking member to achieve retro-reflection either alone or on a geometric retro-reflective surface as inFIG. 11. Such micro-prismatic toothing will help avoid overheating and glare. Also, the micro-structured mirroring may be rolled onto an aluminum substrate, and then glossed, anodized and formed into a desired geometrical shape.

FIG. 2Cillustrates an alternative bearing member structure33having a relief slot35that passes through the annular ring and retention flanges of the bearing member. This slot facilitates mounting of bearing members structured in this way since the bearing member can be pressed together to close the slot when the rings are inserted in the bores. After insertion, the bearing members will be released so that they can spring back to their original configuration ensuring rotatable mounting in the bores. (See also the discussion ofFIG. 17in which a differently configured bearing member is also preferably provided with a relief slot). Such slotted bearing members not only facilitate assembly into the bores but also are forgiving of tolerance variations and thermal expansion/contraction of other components in the light-control assembly.

FIG. 2Ddepicts yet another bearing member design50in which retention flange34, as well as the optional guide and retention tabs are not used and notches52a,52b,52cand52dextend through the rings54but not into retention flanges56thereby establishing a smaller predetermined distance B1between notch bottoms52aand52bwhich is smaller than distance “B”. Additionally, the web portions of the flange below the bottom of each of the notches in this embodiment are thicker than web portions40aand40bsince the notches do not extend into the flanges.

FIG. 3Aillustrates a hemispherical tubular light-controlling member60which may be used with, e.g., any of bearing members30,33or50. Light-controlling member60includes a clear tubular hemispherical portion62and a generally flat opaque or translucent barrier component64. The opaque or translucent barrier component includes ledges65which extend beyond the outer surface of the tubular hemispherical portion. These ledges are dimensioned to rest in notches52aand52bof bearing member50A as shown (or in the corresponding notches of bearing members30or33) while the tubular hemispherical portion preferably fits within the inner wall66of the ring54of the bearing member (or the corresponding inner walls of the rings of bearing members30or33).

FIG. 3Billustrates a 360° tubular light-controlling member67including a clear tubular component68and a generally flat opaque or translucent barrier component69which is mounted across the diameter of the tubular member. The alternative light-blocking members ofFIG. 11may also be used in lieu of component69. Also, the micro-prismatic toothing ofFIG. 12may be employed. A bearing member that may be used with this configuration may comprise, e.g., the structure of bearing members30,33or50, but preferably will not have either notches or tabs. For example, bearing member55having ring57and flange59may be used. In this embodiment, the tubular light-controlling member preferably will fit snuggly against the inner wall61of the ring of bearing member55which itself will be rotatably mounted in bore18.

When reference is made to a feature of the invention as being opaque or translucent it is intended to mean that the feature ranges from translucent (letting some light pass but diffusing it so that objects on one side cannot be clearly distinguished from objects on the other side) to opaque (letting no appreciable amount of light pass). When reference is made to “light” in the description of the present invention this term should be construed to include the spectral range of visible light (with or without the electromagnetic radiation with wavelengths below and above that of the visible light). When reference is made to a light-controlling member as being “spectral controlling” it is intended to mean that one or more selected portions of the spectrum are allowed to pass or are blocked, e.g., that a UV, IR or other wavelength range is allowed to pass or is blocked. When reference to a light-controlling member as being “reflecting” or “reflective” it is intended to mean that some or all of the incident light (including e.g., a selected wavelength range) is bent or sent back from a blocking surface of the light-controlling member.

Any light-blocking components used in the invention, such as the opaque or translucent or spectral controlling barrier components64,69or300a-300o, may be tinted to a level that produces the desired degree of light-blocking. Also, the light-blocking components may be segmented into light-blocking or opaque portions and transparent/translucent portions. For example, in 40-foot light-controlling members, the first 10 feet of one or more of each of the light-blocking components may be opaque, the next 5 feet transparent/translucent, and the last 25 feet opaque. Such a segmented arrangement might be used where it is desired to maintain a light-admitting area at all times. Also, translucent portions may be tinted. Typical tinting colors include white, bronze, green, blue and gray; although other colors may be used. Finally, light-controlling members may have one face (e.g., face165of light control member150or one face of flat portions64or69) and a different treatment on the other face (e.g., face167of light control member150or the opposite face of flat portions64or69). For example, one face may have a reflective surface and the other may have a diffusing surface so that the light-controlling member may be rotated into a first position in which it reflects incoming light away from the covered space and a second position in which the non-reflective surface diffuses the incoming light that strikes it.

The barrier components may include photovoltaic solar cells along their surface to generate electricity, preferably in conjunction with means for maximizing the photovoltaic output by rotating the light-controlling members to track the movement of the sun across the sky, ensuring that the photovoltaic solar cells continuously receive the maximum possible sunlight exposure. This combination provides in a single assembly both effective dynamic control of daylighting and shading and efficient electricity generation.

FIG. 3Cillustrates yet another light-controlling member151comprising a pair of perpendicular cross pieces153and155which preferably are coextruded. Cross piece153is opaque in this embodiment, although it may, of course, have a different surface treatment, as discussed above. Additionally, feet157are formed at the opposite ends of the cross pieces and generally perpendicular to the cross pieces. Preferably, opaque cross piece153passes through the clean feet to maximize light-blocking. Feet157, which will rest against the inner wall74of bearing member55to retain light-controlling member151in place, may be curved to follow the curvature of the inner surface74of the bearing member and preferably will be clear as shown. As a result, opaque cross piece153is positioned and held in place across the diameter of the bearing member and presents minimal light-blocking when light-controlling member151is in the fully open position.

FIG. 3Dillustrates yet another light-controlling member design. This design includes cross pieces159and161which generally correspond to cross pieces153and155ofFIG. 3C. In this embodiment, however, there are no feet. Rather, the ends163of the cross pieces fit in opposed notch bottoms36A-36D and in the guide and retention tabs42A and42B of bearing member30. It should be noted that in the embodiments ofFIGS. 3C and 3Dboth bearing members30and55include retention flanges, but these have been removed for purposes of illustration. Other bearing designs (e.g. bearing members30,33,50or55) may be used with this light-controlling member design.

Turning now toFIG. 4A, an exploded view of light-control assembly10is shown, including a beam70at the center of the assembly having bores18in which the bearing members rotate. Since beam70in this embodiment is made by plastic injection molding for purposes of minimizing friction, weight and material usage, the beam is molded with rings72defining bores18along their inner surface74. Adjacent rings72intersect on their periphery and are joined along lateral conjunction segments76. Preferably, the beam will be made of a clear or translucent material like polycarbonate to help camouflage the light-control assembly. However, the beam may also be made by known techniques using aluminum, steel or other appropriate materials.

At least one and preferably three or more rollers or roller assemblies may be mounted on the beam about the periphery of the bores to contact the outer circular surface of the bearing members. This will help reduce friction and wear particularly in heavy usage applications, where the light-controlling members are heavy, or where it is necessary or desirable to minimize the number of light-control assemblies. Furthermore, where such rollers or roller assemblies are used they may be spaced from the front and back faces of the beam and/or undercut to create a gap for retaining the bearing members in lieu of or in addition to retainers110or310which are discussed below.

The injection molded beam illustrated inFIG. 4Aalso includes top and bottom strips78and80, front and rear faces14and16, and a series of repeating top and bottom support ribs82a-82cdefining cavities83a-83c, as illustrated. The combination of the laterally conjoined rings, top and bottom strips, support ribs and cavities together make the beam lightweight yet give it sufficient rigidity to resist bending forces to ensure reliable operation of the light-control assembly.

The beam ofFIG. 4Apreferably is designed for modular applications where a series of beams having, for example, six bores that are approximately 45 mm in diameter can be easily and reliably interconnected to produce a longer composite light-controlling assembly of a desired width comprising a multiple of the width of a single light-control assembly. For example, such a modular assembly nominally 600 mm in width could be constructed and used in applications where the light-controlling members are any desired length from, e.g., up 15 meter or more.

Thus, the first end84of the illustrated light-control assembly70includes top and bottom trapezoidal projections86aand86bthat fit into trapezoidal cavities102aand102b. Trapezoidal projection86aand corresponding trapezoidal cavity102aare shown in the partial enlarged views ofFIGS. 4B and 4C. InFIG. 4Cit is seen that trapezoidal projection86aincludes a base surface88protruding beyond a generally flat face90of beam end84. Trapezoidal cavity102ais dimensioned to receive trapezoidal projection86a, so that face88of the trapezoidal projection is adjacent to flat bottom surface104of the trapezoidal cavity. Also, beam end100includes a flat face104dimensioned to abut flat face90of beam end84where the trapezoidal projection slides into the trapezoidal cavity as shown inFIG. 4C.

Additionally, flexible locking clips92(FIG. 4A) project from the flat surface90of first end84. These clips are designed to flex inwardly as adjacent beams are moved into alignment and then to lock in place when the adjacent beams are fully laterally aligned.

The trapezoidal projections are aligned and moved into their corresponding trapezoidal cavities as illustrated inFIG. 4B. When corresponding front and back faces14and16of the beams are aligned, clips92will snap into place locking the adjacent beams together. Thus, any number of beams may be locked together in this way to modularly produce an overall light-control assembly of the desired width.

Once the desired number of beams is assembled along with the other components of the light-controlling assembly an optional reinforcement member may be applied across the top and/or the bottom edges of the assembly. For example, a metal U-channel111(FIG. 4A) may be used for this purpose. Such a reinforcement member may also be used to attach the light-control assembly to existing structure under or over glazing or opened unglazed areas using appropriate profiling members. Finally, appropriate holes may be located in the reinforcement member in alignment with bores121in the beam and corresponding holes123in retainers110(see below) and appropriate fasteners (not shown) may be used to insure reliable attachment.

Light-control assembly10, in the illustrated embodiment, also includes pairs of front and back retainers110which are designed to be oriented as shown and attached to the front and back faces14and16of the beams to retain the bearing members. The offset bearing members are thus coupled to the beam by trapping the retention flanges of the bearing members between front and back faces of the beam and the back surfaces116of the retainers. (The top front retainer was removed fromFIG. 4Ato facilitate viewing of the overall assembly.) Retainers110, in the illustrated embodiment, have a scalloped edge with a series of semi-circular openings112each having an inner surface114of a diameter corresponding to that of bores18. As in the case of the beams, the retainers preferably will be made of a transparent or translucent material like polycarbonate to help camouflage the light-control assembly, but can be made of any desired material.

As best seen inFIG. 5A, the back sides122of the retainers include a ridge124with inner surface114corresponding to the inner surface19(FIG. 1) of bores18and an undercut126behind the ridge creating a back face128and an annular cavity131dimensioned to receive and trap flange34of the bearing members without impeding rotation of the bearing members. Thus, the flanges of the offset bearing members are captured in the curved undercuts126of retainers110. Alternatively, such undercuts may be formed in the face of the beam about the circumference of bores18to serve the same function as retainer undercuts126which may instead have a flat inner surface114in such an arrangement. In yet another alternative, both the surface of the beam and the inner surface of the retainer may be undercut so that these undercuts can cooperate in capturing the flanges of the bearing members in place in the light control assembly.

Beams300and402may be adapted for modular assembly like beam70by providing appropriate interlocking means at the ends of the beams.

Additionally, as best seen inFIG. 5Btabs120a,120band120cproject generally perpendicularly from the retainer back surfaces116and are positioned and dimensioned to fit in cavities83a,83band83cof the beam to ensure proper positioning of the retainers on the beams.

Finally, retainers110include alternating locking pins130and locking cavities132which are disposed on the backside of the retainers so that when retainers are positioned on opposite sides of the beam, the locking pins and locking cavities are aligned and paired up so that they can interconnect. These locking pins and locking cavities are illustrated in an enlarged form inFIG. 5B. A pair of fully interlocked pins and cavities is illustrated in the cross-sectional view ofFIG. 5C.

Locking pins130include ribs134a-134dwhich project in diametrically opposite directions and have outer edges that are dimensioned to rest securely within locking cavity132. Additionally, bottom rib134dincludes a nose portion136having a ramp surface138and a locking face140. Locking cavities132also include a tubular portion with longitudinal slits142defining a top flexible tubular portion146.

Thus, when retainers110are properly positioned on opposite faces14and16of the beam with ribs120A-120C aligned with cavities83a-83cand locking pins130aligned within locking cavities132, the retainers are pressed together until they rest against the opposite faces of the beam. Nose portion136is positioned and dimensioned so that as it moves into cavity132the top flexible tubular portion146flexes upwardly as the nose portion flexes downwardly until the nose portion hooks onto a latch bar147whereupon the locking pins lock in the cavities affixing the retainers onto the front and back of the beam. Additionally, when multiple beams are joined together, the retainers will be offset as shown inFIG. 4Ato cover the seams between adjacent interlocked beams and enhance the security of the attachment.

However, before the assembly of the retainers onto the beams is completed, a first bearing member30is mounted in a first bore such as bore18aofFIG. 1with its flange34adjacent the first beam face14and its ring extending into the bore. The next bearing member is mounted in the next adjacent bore such as bore18bofFIG. 1with its flange adjacent the second beam face16and its ring extending into the bore. The bearing members are mounted in each successive bore in this alternating fashion, so that looking atone of the faces of the beam, the flanges are at the front of every other bore. Looking at the opposite face of the beam, the flanges will be in the remaining alternate bores. This insures that the flanges in adjacent bores will not interfere with each other. In one alternative embodiment of the invention the retainers may be secured to the beams with screws or other fasteners that pass through holes123in the retainers and into bores121in the beam which are aligned with the holes.

FIGS. 13-16illustrate an alternative light control assembly design. This light control assembly includes a generally flat alternate beam design300ofFIGS. 13 and 13Ahaving a series of circular bores302which pass through the central section of the beam303and define web portions304between the bores. Top and bottom ribs306and308are located at the top and bottom of the central section of the beam.

FIGS. 14 and 14Adepict an alternative U-shaped retainer design310. Retainer310as best viewed from its end312includes a front leg314and a back leg316defining an opening318between the two legs. A channel320is formed at the top of opening318to receive top rib306of beam300. Retainer310also includes scalloped edge321with circular openings322corresponding in diameter to the diameter of bores302. As in the case of retainer110, retainer310is undercut at324to receive bearing member326as will be explained below.

Bearing member326comprises a flat annular ring328with pairs of diametrically opposed notches330having opposed notch bottoms332generally corresponding to notches36a-36dand notch bottoms38a-38dof bearing members30. Bearing member326also includes a circular outer edge334as depicted inFIG. 15A.

A fully assembled alternate light control assembly400is shown inFIGS. 16 and 16A. This assembly is constructed by aligning bearing members326aand326bwith adjacent bores302with each adjacent bearing member offset with respect to its adjacent bearing member(s), i.e., on opposite sides of the beam. The rings preferably overlap the web portions between adjacent bores. With the bearing members positioned in this way retainers310are pressed down upon the top and bottom ribs of beam300to generally spread the legs of the retainer until the ribs come to rest in channels320whereupon the legs of the retainer snap back in place, locking retainers to the top and bottom ribs of the beam and thereby capturing the offset-positioned bearing members in assembly400. As can be seen in FIG.16, the outer edges of the bearing members are captured within undercuts324(FIG. 14) in retainers310. In a yet further alternative embodiment, such undercuts may be provided along the outer edge of bores302in lieu of or in addition to undercuts324of the retainers to perform the same retention function.

Turning now toFIG. 17, an alternate beam design402is shown with bores404aand404b. These bores have respective inner surfaces406aand406bwith circular grooves408aand408bthat are offset with respect to each other as shown. This beam will thus accept and retain, e.g., bearing members30,33,50,55, and326. In the case of all but bearing member33, the bearing members will be forced into the bore grooves. Slot35in bearing member33is therefore preferred in the sense that relief slot35makes it easier to squeeze this bearing member together before insertion released so that when it is released flanges34will rest in the appropriate grooves to complete the assembly. Similar relief slots or other relief means may be provided in any bearing member intended to be mounted in bores404aand404b. Additionally, it is noted that when using a beam design like that of beam402, the bearing member flanges may be shifted from the outer ring edges to intermediate locations along the outer surfaces of the annular rings of the bearing members to engage grooves406aand406b.

Light-controlling members such as slats150ofFIGS. 6A and 6Bmay be mounted in the bearing members described above. Slats150, in the illustrated embodiment, are plastic extruded to form top and bottom walls152and154. Walls152and154are each made up of a central segment156and lateral segments158which define lateral cavities157and central cavity159. The slats may be opaque or translucent. An air space160is maintained between the top and bottom walls by forming ribs162which, in the illustrated embodiment, are disposed perpendicularly at the lateral edges of central segment156. Slat150also has a front face165and a back face167. Also, in the illustrated embodiment, holes164are formed in the central segment adjacent the drive end166of the slats to facilitate locking the slats to a drive mechanism250as shown inFIG. 8, as discussed below. This segmented configuration gives the slats important rigidity characteristics while maintaining light weight and producing minimal interference with light transmission when the assembly is in a fully open position.

The illustrated configuration of slats150(as well as slats151and166) gives them longitudinal, torsional, and deflection rigidity, which is desirable in the practice of this invention. The term “torsional rigidity” is intended to refer to the ability of the slats to resist deformation when forces are applied to rotate them within the light-control assembly. “Longitudinal rigidity” is intended to refer to the ability of the slats to withstand deformation or deflection when a force is applied generally along the longitudinal axis of the slats such as when the slats are slid into the light-control assembly, as will be described in more detail below. “Deflection rigidity” is intended to refer to the ability of the slats to withstand bowing under the force of gravity or other forces which act generally perpendicularly to the longitudinal axis of the slats.

The top and bottom walls of slat150join together to form top and bottom edges168and170. In the illustrated embodiment, these edges are dimensioned to fit into the opposed slots36aand36bof bearing members30although they may, of course, be used with other bearing member designs. Thus, when the mounted slats are rotated into the closed configuration illustrated inFIG. 6Blight will be able to pass only in the gap172between the adjacent slats.

FIG. 6Cis a diagrammatic representation of two slats150resting within slots36aand36bof bearing member30(FIG. 2B). In this diagrammatic representation retention flange34of the left bearing member will rest against back face16of beam70while retention flange of the right retention flange34of the right bearing member will rest against front face14of beam70. Since the retention flanges of the bearing members are offset in this fashion they do not interfere with each other and thereby make it possible to bring corresponding edges170of the two slats far closer together than has been conceived of or implemented in any prior art light-control device.

In an alternate embodiment of the invention, slats174ofFIG. 6Dwill be provided with deformable top and bottom edges180and182as illustrated in this Figure by extruding deformable edge shapes, co-extruding flexible edges or otherwise attaching deformable strips184to top and bottom edges180and182. Thus, when these slats are in a fully closed position corresponding generally to that depicted in the partial overhead view ofFIG. 6Evirtually all of the space between adjacent slats will be closed off by the deformable edges as illustrated.FIG. 6Fis a diagrammatic representation corresponding generally toFIG. 6Dwhich highlights the contact between deformable edges180and182of slats174made possible by offsetting the retention flanges of the bearing members on opposite sides of the beam.

Slats150and174may include photovoltaic solar cells to general electricity, preferably in conjunction with means for maximizing the photovoltaic output by rotating the light-controlling members with movement of the sun across the sky to insure that the photovoltaic solar cells continuously receive the maximum possible sunlight exposure while providing daylighting into the space below.

FIG. 7illustrates another important feature of the slats of the invention with respect to slat design186in which, for purposes of illustration, triangular top and bottom segments187with opposite beveled faces190and192are emphasized. Angles “C” and “D” of triangular top and bottom segments187preferably should be greater than 45 degrees. Slats186may be fit within bearing members in the same fashion as slats150and174, described above. In accordance with the teaching above, segments190,191and192(and preferably the corresponding segments on the opposite face of the slat) will be opaque, translucent, spectral controlling or reflective. Thus, when slat186is in the fully open position illustrated in this figure and segment190has a reflective surface most of the incoming light hitting that surface will be reflected into the area below shown diagrammatically as an enclosed area196. When segment190is, e.g., white opaque, an estimated 60% of the incoming light hitting that surface will be reflected into the area below. Finally, when segment190is translucent an estimated 30% of the incoming light hitting that surface will be reflected into the area below. This is depicted diagrammatically inFIG. 7which shows light rays194aand194bstriking surfaces190and192of adjacent open slats and being directed downwardly to the area below the slats. Of course, when the slats are rotated 90 degrees to their closed position, they will block, reflect, etc. some or all of the incoming light, as described earlier.

Finally, it is noted that the light-reflective surfaces of segments190,191and/or192may be micro-prismatic reflective surfaces. Total light enhancement can be achieved by positioning such micro optical prisms to tunnel additional light into the interior space below the light-controlling members.

A drive mechanism200that may be used in the invention is illustrated inFIG. 8. The drive mechanism includes a gear box202having a shaft204with a mounting comb206having tines208positioned and dimensioned to fit within lateral cavities157of slat150and a central member210dimensioned and positioned to fit within the central cavity159of slat150(FIG. 6A). The mounting comb thus retains the slat on the drive mechanism. Central member210may also have a projection (not shown) that fits in hole164of the slat to lock the slat onto the comb.

Worm gear212(mounted onto shaft204of the mounting combs) meshes with an internal worm (not shown) having a circular axial cavity216with a key218. Thus a rotation shaft22with a corresponding slat to receive key218is designed to be passed through cavities216of drive mechanisms200associated with each of a series of slats in a modular light-control assembly. As a result, rotation of the shaft will produce corresponding and coordinated rotation of all of the slats associated with drive mechanisms attached to the shaft.

This is illustrated inFIG. 9which shows, at the top of the figure, a series of 12 slats150in the closed position above a series of 12 slats in the open position at the bottom of the figure. The slats are supported in a light-control assembly10which is shown at the left of the figure, rotated 90 degrees to better view of the light-control assembly. In fact, a series of such light-control assemblies will be spaced along these slats at appropriate distances to ensure that the slats are maintained properly in position. The light control assemblies can be mounted in side beam226as shown inFIG. 9A. It should also be noted that each light-control assembly10in this figure comprises two beams, each having six circular bores18joined at their corresponding trapezoidal projections and trapezoidal cavities, as discussed earlier.

Looking to the right top ofFIG. 9, a series of 24 drive mechanisms200is shown each with mounting combs206. While the mounting combs are shown removed from the slats for purposes of illustration, in operation the mounting combs, of course, will be positioned in the ends of the slats, as described earlier. Finally, shaft222passes through keyed circular openings218in each of the drive mechanisms. Thus, a motor224attached to the shaft can be used to simultaneously rotate all of the slats. Finally, connectors228may be used to create as wide assembly as needed by connecting a series of shafts222. For example, in one modular single motor design, an assembly of 40′ wide×40′ long can be constructed with up to 240 slats operated by a single motor.

A light-control assembly10in accordance with the invention (such as that ofFIG. 1) may be used in a variety of different applications. For example, it may be mounted between clear or translucent panels250and252as in the embodiment ofFIG. 10A. Alternatively, the light-control assembly may be mounted under a clear or translucent sheet254as shown inFIG. 10B(or it may be mounted over a clear or translucent sheet). Additionally, the light-control assembly may be mounted under a skylight256as shown diagrammatically inFIG. 10C. Alternatively, a light-control assembly may be disposed vertically as shown inFIG. 10Dor at inclined angle as shown inFIG. 10E. In yet other embodiments, the light-control assembly may be used in curved applications, as depicted inFIG. 10F. Although the depictions ofFIGS. 10D-10Fare comprised only light-controlling members150and supporting light-control assemblies10, they may be used with any appropriate light-controlling members and they may be disposed under, over or adjacent to clear or transparent sheets or between pairs of clear or transparent sheets. Finally, the light-control assembly may be used without clear or translucent sheets or panels to shade open unglazed areas.

Panels and sheets250,252,254and skylight256may be made of various transparent and translucent materials, including, but not limited to, plastics (including, e.g., polycarbonates and acrylics), fiberglass, perforated metal fabric, or glass. In one preferred embodiment, a Pentaglas® honeycomb polycarbonate translucent panel available from CPI Daylighting Inc. (Lake Forest, Ill.) will be used in these applications. These polycarbonate panels, which are described in U.S. Pat. No. 5,895,701 (incorporated herein by reference), have an integral extruded honeycomb structural core consisting of small honeycomb cells approximately 0.16 inch by 0.16 inch which provides internal flexibility to absorb expansion and minimize stress and resists impact buckling. The resulting design offers smaller spans between rib supports, resulting in stronger durability, as well as superior light quality, visual appeal, higher insulation and excellent UV resistance. The internal flexibility of the panels absorbs thermal expansion through the panel in all directions (on the x, y, and z axes). This minimizes stress in all directions and preserves dimensional stability. The panels also have a high impact absorbing and load bearing property, a good ratio of weight to strength, and UV protection on both sides of the panel. The superior light diffusion capabilities ensure excellent quality of natural light. The panels are environmentally friendly, non-toxic, and made of 100% recyclable material.

Also, the light-control assembly may be provided with automatic sun tracking, with appropriate embedded programming that senses the daylight outside and manages the level of light and solar heat gain inside based on the level of sunlight outside. This will enable users to control natural daylight and comfort levels in any space—whether covered by glazing or not—all day long, and all year long, simply by setting desired light levels.

The beam, retainers, and light-controlling members may be made of any desirable material. In one preferred embodiment, these components may be injection molded from polycarbonate resins or acetyl. Preferably at least the bearing members and more preferably all of the components of the light-control assembly will be molded from polytetrafluoroethylene-infused polycarbonate resins. Also, although in the illustrated preferred embodiment the beam, bearing members, retainers, and slats are injection molded, one or more of these components may be made in other ways and may be made of other materials, as appropriate. For example, beam70may be made of punched aluminum.

A light-control assembly generally as inFIG. 1may be assembled as follows:

1. A beam70is provided and a series of bearing members, such as bearing members30, mounted in the bores of the support member with the retention flanges of adjacent bearing members alternating from face to face of the beam (and thus offset) so that no two flanges are adjacent each other on the same face of the beam and the flanges preferably overlap the web portions between adjacent bores.

2. Retainers110are positioned on opposite faces14and16of the beam so the tabs120a,120band120cof the retainers fit in cavities83a,83band83cof the beams and locking pins130are pressed home in locking cavities132. The retainers are thus locked to the beam with the retention flanges of the bearing members trapped between the back face129of the retainer on the opposite faces of the beam.

3. Optionally, the desired number of light-control assemblies10are interconnected by aligning trapezoidal projections86aand86bat one end of the beam of each assembly with trapezoidal cavities102aand102bat the other end of the adjacent beam whereupon the projections are slid into the cavities until the adjacent beams lock together, as described earlier, to form an enlarged modular radiation control assembly of the desired length. Also, where two or more beams are laterally connected to form an enlarged assembly, multiple pairs of retainers preferably will be applied offset with regard to the seam between the adjacent interlocked beams to further reinforce the assembly.

4. A series of radiation control assemblies are then positioned longitudinally under, above, between or adjacent the glazing that is to be treated by the light-control assembly with the bores of the radiation-control assemblies aligned. The radiation control assemblies are mounted in place by appropriate means such as by using side beams226(FIG. 9A). For modular “cassette” design a mounting jam can be used.

5. Next, light-controlling members such as slats150or174of the appropriate length are slid into place in the laterally aligned bores of the bearing members so that they are supported within the successive light-controlling assemblies. In the case of slats150and bearing members30, the slats will be slid into diametrically opposed notches36aand36bso that the opposite top and bottom edges168and170of the slats rest in opposed notch bottoms38aand38b. The longitudinal rigidity of the slats ensures that they can be slid into place in the successive bearing members without buckling. The torsional rigidity of the slats ensures that the slats can be rotated from one end with twisting out of shape. Finally, the deflection rigidity ensures that, one in position, the slats will not sag. Furthermore, it is noted that the overall assembly is thus readily assembled on-site and that can be used in both new construction and retrofit applications. It also ably accommodates thermal expansion and contraction of the components of the assembly, including the light-controlling members, when the assembly is subjected to wide-ranging temperature changes at the site of installation. The slats can move longitudinally within the bearing members free from the limitations imposed by rings and notches as they lengthen or shorten due to temperature swings.

6. Then, the slats are aligned and appropriate drive means attached to the control ends of the slats. “Aligned” in this context means that the slats will be parallel to each other when in the fully opened position and co-planer when in the fully closed position.

7. The resulting light-control assembly is now ready to provide light-blocking from almost full transparency to total black-out or near total black-out at a level of reliability which has heretobefore not been possible.