Abstract:
A luminaire having a tubular body that fits into a ceiling mounted sleeve that allows azimuthal rotation of a light beam. The luminaire features an upright tubular heat sink connected to a fixed base having a downward portion inclined at an angle where an LED chip is affixed. The chip is sandwiched in place by a reflector holder having a rim that centers a rotating reflector that admits light from the LED and forms a beam. The angular inclination of the reflector is additive with the angle of the inclined portion of the base allowing vertical angle adjustment of the beam independently of the azimuthal adjustment.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority from provisional application Ser. No. 61/884,093, filed Sep. 29, 2013. 
    
    
     TECHNICAL FIELD 
     The invention relates to decorative luminaires, and in particular to a variable angle, variable beamwidth, ceiling mounted luminaire. 
     BACKGROUND ART 
     In U.S. Pat. No. 2,716,185 D. Burliuk and E. Rambusch devised a luminaire construction that featured a selectively titling luminaire that could be installed in a mounting ring either entirely from below a ceiling or entirely from above the ceiling. The luminaire has a finishing plate mounted to a ceiling that is apertured to admit a lamp and to allow the light to escape. This plate supports two housing members, the lower of which is adjustable about a vertical axis, allowing tilting of the lamp, while the upper is adjustable on the lower about a sloping axis. The upper part carries the lamp, wiring and a cooling structure. By reaching through the aperture in the finishing plate, a user can adjust the lamp housing parts about the respective axes so as to vary the slope of the lamp axis and its orientation about the vertical axis. This dual adjustability of the beam slope and orientation have largely been overlooked in modern lamps. Beam slope is adjustable by forming the lamp housing in two portions including a peripheral spherical upper portion that is trimmed to a 22.5 degree angle and a lower portion, also having a peripheral edge trimmed to 22.5 degrees, with the lower portion rotatable relative to the upper portion, being held in position with clips. By rotating the lower portion relative to the upper portion, the beam angle may be adjusted at radial angles ranging from 0 degrees to 45 degrees in a selectively tiltable manner. Moreover, once a selected angle is set, the fixture may be axially rotated about 360 degrees of the vertical axis so that the beam may be directed in any desired direction. 
     A selectable tilt, similar to the &#39;185 patent is described in U.S. Pat. No. 6,152,571 where two angled plates surrounding a lamp and beam rotate relative to each other so that a selected angle of the beam relative to a flush mount may be set, where the selected angle is relative to the beam direction. In U.S. Pat. No. 7,303,327 S. Copeland and M. Thompson describe an LED in which the direction of the emitted light can be controlled by adjusting a portion of the housing and/or by controlling the orientation of the LED array within the housing. In. U.S. Pat. No. 8,029,158 J. Chen describes an LED light module that includes heat dissipating radial fins. Heat generated by the LED light is conducted from a flat portion of the LED to the fins for dissipation. Another such structure is shown and described in U.S. Patent Publ. 2012/0281409 to S. Patkus et al. In U.S. Pat. Nos. 8,042,973; 8,047,687; and 8,079,736 M. Inoue et al. describe use of multiple LEDs with multiple reflector sections within a tubular heat sink structure with fins extending in the axial direction. U.S. Patent Publ. 2012/0320577 shows a titling LED lamp structure that includes radial fins in the axial direction. 
     One of the problems of the tilting lamps of the prior art is that the radial swing of a mounted lamp housing can interfere with wiring or cabling in a ceiling that is installed subsequently in the vicinity of the housing. As the housing is rotated it can sometimes contact nearby wiring causing wear on the insulation of the wiring or, in extreme cases, shorting of the wiring or the lamp. 
     SUMMARY DISCLOSURE 
     The invention is a luminaire of the type intended for mounting in a ceiling or the like. The entire profile of the device is cylindrical, including a rearwardly extending tubular heat sink with a central axis that remains stationary, unlike prior art luminaires that tilted in order to tilt an emergent beam. The present invention can vertically tilt an emergent beam while remaining stationary in a upright position and also swing the beam to a desired azimuthal angle. In other words, the present luminaire has a variable lateral angle beam as well as azimuthal rotation of the entire assembly, giving two independent angular beam motions. For example, a beam from the luminaire can be pointed to a spot on a wall, then the angle of the beam relative to the spot, up or down, can be changed, and the luminaire can be rotated so that a different wall spot is illuminated. 
     Forward of the stationary heat sink are rotational components, including a rotating reflector that reflects light from an attached light emitting board and a base member that supports the board and the reflector. The base member has one surface end joined to the heat sink while the opposite end surface is inclined at a first angle relative to the axis of the heat sink. At the same time, the reflector has a peripheral portion inclined at a second angle relative to the axis of the device such that rotation of the reflector causes additive combination of the first and second angles to achieve a desired amount of beam-tilt. A typical range of tilting extends from zero degrees, where the beam is axially symmetric, to 45 degrees. To achieve a 45 degree tilt, each of the first and second angles would be 22.5 degrees so that the additive combination is 45 degrees. The reflector has a radially inward tapered cylindrical surface reflective of light into a cone, allowing light from the light emitting board to pass into the center of the reflector where a beam is given its shape. A cylindrical housing can surround the reflector and a portion of the base. The housing coaxially fits within a fixed tubular mounting sleeve, usually attached to a ceiling. Rotating the housing within the fixed sleeve gives the second rotational opportunity for the beam independent of reflector rotation with the attached base. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a side view of a luminaire of the invention mounted in a ceiling. 
         FIG. 1B  is a side view of a type of luminaire of the prior art mounted in a ceiling. 
         FIG. 2A  is an upper perspective view of the luminaire shown in  FIG. 1A . 
         FIG. 2B  is a lower perspective view of the luminaire shown in  FIG. 1A . 
         FIG. 3A  is a fully exploded, partial x-ray side view of components of the luminaire of  FIGS. 2A and 2B . 
         FIG. 3B  is a fully exploded side view of components of the luminaire of  FIGS. 2A and 2B  with the orientation of  FIG. 3A . 
         FIG. 3C  is a fully exploded side view of components of the luminaire of  FIGS. 2A and 2B  with an orientation that is rotated ninety degrees clockwise relative to  FIG. 3B . 
         FIG. 4  is a side exploded view of components of the reflector shown in  FIG. 3A . 
         FIG. 5A  is the luminaire of  FIG. 1A  with a reflector orientation in a first position. 
         FIG. 5B  is the luminaire of  FIG. 5A  with a reflector orientation in a second position. 
         FIG. 6A  is an exploded perspective view of a ceiling mounting fixture for the luminaire of  FIG. 1A . 
         FIG. 6B  is a perspective view of the mounting fixture of  FIG. 6A  shown in a portion of a ceiling. 
         FIG. 7A  is a luminaire of  FIG. 1A  being inserted into the mounting fixture shown in  FIG. 6B . 
         FIG. 7B  is a side x-ray view of the luminaire shown in  FIG. 2A  in the mounting fixture. 
         FIG. 7C  is sectional view taken along lines  7 C- 7 C of  FIG. 7B . 
         FIGS. 8A ,  8 B, and  8 C are perspective operational views showing three different angles of beam tilting with rotation of the reflector components similar to the reflector components of  FIGS. 5A and 5B . 
     
    
    
     DETAILED DESCRIPTION 
     With reference to  FIG. 1A , a luminaire  11  of the present invention is shown mounted in a ceiling, C, directing a beam of light downwardly. The luminaire  11  is seen to be tubular in overall construction with the beam, B, being symmetric about a cylindrical axis. It is desirable to have the beam tilt and rotate. In the prior art this was accomplished, as shown in  FIG. 1B , where a luminaire has a first position, S1. In order to tilt the beam, the rear portion fixture was tilted as shown by the luminaire in position, S2. A problem that occurs is that if a ceiling cable or pipe, W, is placed next to the luminairing position, S1, the wire, W, interferes with tilting and, some instances, prevents tilting. On the other hand, the luminaire of the present invention allows tilting and/or rotation of the beam, keeping the tubular body stationary. Any cables or wires placed next to the luminaire are inconsequential. 
     With reference to  FIG. 2A , the luminaire  11  is seen to have a generally tubular heat sink body with a central axis, X, that is coaxial with a central hole  21 . The central hole is used to pass an electrical temperature probe to reduce power to an LED if overheating is detected. Alternatively, electrical wires coming from an external location could supply power to an LED lamp, described below. The heat sink body has radially extending fins. The heat sink  13  is connected to a base  15  which in turn is connected to a cylindrical housing  17 . 
     In  FIG. 2B , all of the components shown in  FIG. 2A  may be seen, together with reflector  19  which directs a beam of light out of the luminaire as described below. The reflector  19  is associated with a light source which may be an LED source, or another source, preferably a semiconductor source. 
     Details of the reflector structure may be seen in  FIG. 3A  where the reflector  19  is shown above its housing  17 . The interior of the reflector may be a reflective coating, such as a vapor deposited aluminum coating, or a thin shell of reflective material. Base  15  may be seen more fully and separated from heat sink  13 . Sandwiched between the base  15  and reflector  19  is light emitting board  25  that carries an LED chip, or the like. The board is a substrate having a semiconductor light emitting chip adhered to the board for example by surface mounting. The board can be held in place by screws, such as the screw  30 . 
     The base may be secured to heat sink in a fixed position by means of screws, such as the screw  40 . The base  15  is seen to have a first surface  41  which is joined to a first end  43  of heat sink  13 . A second surface of base  15  has a major portion  45  inclined at a first angle relative to the axis previously described. The term “major portion” does not refer to size but to function, as in “significant” portion”. The base.  15  serves as a support for reflector  19  which is connected by magnets. The reflector  19  sandwiches the light emitting board  25  and the reflector holder  27  in a contacting relationship among the members. The reflector  19  is joined to the light emitting board  25  by the intervening reflector holder  27  which has a flanged rim  29  that surrounds the periphery of reflector allowing rotation of the reflector in the reflector holder. The reflector is held to reflector holder  27  by magnets  49 . 
     The central portion of the reflector has a tapered cylindrical surface that is reflective of light into a cone. The tapered surface has an open narrow end  33  and a wide end  35  through which a light emerges in a beam. The wide end may be closed by a diffuser and/or a lens  37 . The tapered surface  31  is reflective of light into a cone or a divergent beam. The tapered cylindrical surface of the reflector has an axis which is inclined at an angle relative to the major axis of the heat sink. 
     The angle of the second surface  45  of base  15  is seen to be a different angle from the angle made by the wide end  35  of the reflector  19 . However, as the reflector rotates, the difference between the two angles will vary as described below with reference to  FIGS. 8A-8C . Rotation of the reflector  19  may be done by hand, merely rotating the reflector within the reflector holder  27 . Rotation is permitted because the reflector is joined to the reflector holder by small magnets  49  in the upper open narrow end of the reflector. The reflector holder  27  is made of a ferromagnetic material that allows joinder of the reflector to the reflector holder, as well as rotation of the reflector on the fixed reflector holder. 
     In  FIGS. 3B and 3C , the components described above may be seen in two different angular orientations. In the first angular orientation of  FIG. 3B , the reflector  19  is seen being connected to base member  15  with the intervening light emitting board  25  and the reflector holder  27  held in place by screw  30 . The reflector  19  will direct light at a oblique angle, rather than directing light downwardly. The oblique angle is variable as the reflector  19  is rotated in the reflector holder  27 . Where a surface of the base is inclined at a first angle relative to the cylindrical axis and the wide end of the reflector has a major peripheral portion inclined at a second angle relative to the axis of the cylinder, the two angles are additive with total angle changing as the reflector  19  is rotated in the reflector holder  27 . 
     As previously mentioned, the beam angle can vary from zero to 45 degrees, or more. The angle of the base and the angle of the reflector are additive, so that any beam angle can be created. In  FIG. 3C , the luminaire reflector is shown rotated by 90 degrees. Magnets  49  on the backside of the reflector allow joining of the reflector to the reflector holder  27 . The chip board  25  is seen to support an LED semiconductor chip  26  that is held in place by screws  30  extending through the reflector holder  27  and into the base member  15 . Chip  26  may be a surface-mounted light emitting diode that receives power through the backside of the board by means of wires extending through the base member  15  and through the central axis of the heat sink  13 . Light from the chip  26  goes through a central aperture  28  in the reflector holder  27  and through an aperture  50  in reflector  19  where a beam is formed. The light beam passes into housing  17  and exits the fixture. 
     With reference to  FIG. 4 , reflector  19  is seen to have several optional closure members at the output end of the reflector including an optional filter member or color modification film  32 , an optional diffuser  34 , and an optional focus lens  36 . Positions of these elements may be interchanged or varied. The lens may be convex, concave or with combined surfaces including a planar surface. One or more of these optional components may be used either alone or in combination with each other. 
     In  FIGS. 5A and 5B , reflector  19  has the truncated conical reflective surface  31  in different positions as the reflector  19  is rotated in the reflector holder  27 , supported by base  15 . In the arrangement of  FIG. 5A , the reflector is seen to have a tapered conical reflector surface  31  inclined at an oblique angle relative to the axis of the heat sink. On the other hand, when the reflector is rotated in the reflector holder  27 , the conical reflector surface  31  is seen to change in orientation so that an output beam will be approximately axially aligned with the heat sink. In both cases, light passes from the reflector  19  into the housing  17  and then exits the device. Cylindrical housing  17  abuts an amount of the base to a slight step where it is stopped so that the housing cannot overlap or surround the upper circumferential portion of the base. The cylindrical housing extends axially forwardly of the base so that the reflector is protected. 
     In  FIG. 6A , a tubular mounting sleeve  41  is seen to have peripheral threads  43  that engage an aperture Y in ceiling C. The tubular mounting sleeve is hollow to receive the luminaire. An indented circular rim  45  engages with protrusions in the base member. In  FIG. 6B , the tubular mounting sleeve  41  is seen to be fully seated in the ceiling C. 
     Note that no screws or clips are required to mount the sleeve  41  to a ceiling. The sleeve  41  is self-mounting, threaded into place with no separate operation required to secure it. Since the sleeve protrudes into the space beyond the ceiling, there is additional surface area for support of the luminaire within the sleeve and above the ceiling. The sleeve has dual external threads, equally spaced on the circumference of the sleeve, each thread having a separate start and end point. By using more than one thread the sleeve is more likely to be threaded straight into a hole. 
     There is a small radially protruding lip near the downward end of the sleeve. This lower lip acts as a stop so that the shroud cannot be threaded indefinitely into the hole but is stopped slightly beyond the thread pattern. Without the lip it is possible to thread the sleeve all the way through the ceiling so that it falls to the other side. The threads have a non-standard, relatively large pitch so that the spacing between the threads is large. For example, for a sleeve having a 2 inch diameter, a one-quarter inch pitch would be typical. By using a large pitch fewer revolutions are required to thread the sleeve into place. Larger pitch also keeps brittle material such as Sheetrock™ from cracking. 
     The lower internal periphery of the sleeve can have axial tool slots parallel to the axis of the sleeve, i.e., indentations in the sleeve material, for receiving a tool that turns the sleeve. The number of tool slots is arbitrary but sufficient for overcoming threading resistance. An internal circumferential rim  45  in the sleeve can be designed to accept the spring plungers or protrusions  47  in  FIGS. 5A and 5B , thereby holding the luminaire in place in a ceiling. 
     In  FIG. 7A , the heat sink  13  is shown being inserted into tubular mounting sleeve  41 . The mounting sleeve is seen to be held in place by threads  43  which are engaging the aperture of ceiling C. As the luminaire is raised in the direction of the arrows S, the protrusions  47  will engage the indented rim  45  within the tubular mounting sleeve. The rim  45  is sufficiently elevated in the tubular mounting sleeve so that the mounting sleeve totally encloses, or at least substantially encloses the cylindrical housing  17  of the luminaire, as seen in  FIGS. 7B and 7C . In  FIG. 7B  the tubular mounting sleeve  41  is seen to be engaged with and by the protrusion  47  in base  15 . Threads  43  of mounting sleeve  41  are seen to be threaded into ceiling C. The axis of heat sink  13  is approximately vertical with respect to ceiling C, while light can emerge at a selected angle, depending upon rotation of the reflector member at the same the azimuth of the entire apparatus can be changed by rotating the cylindrical housing  17  within the tubular mounting sleeve  41 . 
     In  FIGS. 8A ,  8 B, and  8 C, rotation of the reflector member  19  can be seen. In  FIG. 8A , the reflector will direct light obliquely to the left as the reflector is rotated clockwise. In  FIG. 8B , the reflector will direct light toward the back plane of the paper. Counter clockwise rotation is shown in  FIG. 8C  will direct light straight down as the reflector  19  is rotated.