Abstract:
A lamp assembly adjustable between narrow beam and wide beam light distributions, the lamp assembly is particularly intended for housing lamping or the like for mounting to industrial emergency unit fixtures of differing size and conformation. At least one and preferably two of the lamp assemblies are mounted to a unit fixture in spaced relation to illuminate critical areas within an industrial or commercial space during emergency conditions, such as failure of mains power, to allow evacuation of the space. In order to illuminate the desired areas, each of the lamp assemblies can be adjusted along an internal track to allow light to be directed toward a particular location within a wide range of possible locations, thereby facilitating illumination of the most desirable area in the vicinity of the unit fixture for a particular mounting location. Additional flexibility in the delivery of illumination to a desired area is provided by adjustability between narrow and wide beams.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates generally to emergency unit lighting fixtures and particularly to lamp assemblies usable with such fixtures and which are both adjustable as to the direction in which light is directed and as to beam width. 
     2. Description of the Prior Art 
     Emergency unit lighting fixtures have long been known in the art and have long been required by code for illumination of egress pathways, doorways and the like for facilitating evacuation of a building, typically a commercial or industrial space within a building, during emergency conditions which usually are accompanied by failure of mains power supply resulting in loss of usual illumination sources. Emergency unit fixtures typically take the form of a housing within which an emergency power supply, usually batteries, and circuitry are disposed for driving one or more lamps mounted to the exterior of the housing. In most typical unit fixtures, a pair of lamps are mounted to the top of a unit housing with each lamp being directed forwardly and to the side of that side of the housing on which the lamp is mounted. Such unit figures are often referred to as “frog eyes” and typically do not include a “legend” as do exit signs, thereby allowing use of unit fixtures in locations inappropriate for an exit sign. Further, a unit fixture is intended to provide a usable amount of light, such as along a hallway or the like, to enable a person evacuating a space to follow a preferred pathway out of that space. As disclosed by Edstrom in U.S. Pat. No. 4,422,069, the external lamps of such unit fixtures provide illumination incident on desired surfaces so that a person evacuating the space within which an emergency exists will be able to see a pathway or an exit inter alia. Typical unit fixtures are disclosed by Heffner et al in U.S. Pat. No. 4,218,725. 
     Emergency unit fixtures have primarily found use in commercial environments which have previously included industrial environments. However, in spite of prior usage of this type of lighting fixture in industrial environments, a need has continued to exist for improved emergency unit fixtures mountable virtually anywhere within an industrial environment and lamped with illumination sources having desirable characteristics. Further, a need exists in the art for emergency unit fixtures useful in industrial environments whereby light from appropriate lamping can be directed to a particular location within a wide range of possible locations within the industrial space proximate to the unit fixture. Still further, need has existed for control of a light beam emanating from lamping of an emergency unit fixture so that the beam can be adjusted between narrow and wide beam conformation. The present invention provides emergency unit fixtures capable of withstanding the abuse typically encountered in industrial environments, the unit fixtures being mountable to a variety of structure within the industrial environment and further being comprised of at least one lamp assembly movable relative to a housing of the fixture in a swiveling motion and further being movable along an internal track within the assembly to allow light emanating from the lamp assembly to be directed as desired to illuminate a particular area chosen for criticality in evacuation of the industrial space or for some reason of importance. The illuminating beam provided by the lamp assemblies of the invention can be adjusted between narrow beam and wide beam light distributions to provide flexibility in operation of the emergency unit fixtures so configured. 
     SUMMARY OF THE INVENTION 
     The invention provides an emergency lighting unit fixture particularly useful in industrial environments and which provides “unit” emergency lighting by the disposition of one or more lamp assemblies mountable to any one of a variety of unit fixture housings of different size and conformation. Lamping is mounted by a lamp holder capable of swiveling movement which allows movement of the lamp assemblies with a very substantial degree of freedom to facilitate illumination of particular areas proximate to the fixture. Internal track elements formed within each lamp assembly allows additional adjustment of the lamp assembly in order to direct light toward desired locations within a wide range of possible locations. The structure of at least certain of the elements forming each lamp assembly is spherically concentric thus yielding a compact profile which is attractive in appearance and is further functional due to volumetric efficiency inter alia. 
     Illumination provided by a preferred embodiment of the present lamp assemblies when in use with industrial emergency unit fixtures is flexible in its application to a desired area to be illuminated due to the ability of the present lamp assemblies to be adjusted between narrow and wide beam conformations. In essence, the beam emanating from each lamp assembly can be adjusted between narrow and wide beam in order to provide a desired type and intensity of lighting to an area which is to be illuminated. Adjustment of beam width is readily and rapidly accomplished by simple manual manipulation of an external bezel which also holds a lens and reflector to an assembly housing, the bezel being movable along sloped tracks formed integrally on exterior surfaces of the lamp housing and under spring pressure in order to adjust beam width. Accordingly, beam width can be adjusted as desired for a given illumination situation with a given lamp assembly on one unit fixture being differently adjusted from the adjustment of any other lamp assembly carried by said unit fixture. Between given limits of narrow and wide beam positions, the lamp assembly is essentially infinitely adjustable. 
     The emergency unit fixtures described herein as well as the adjustable lamp assemblies operable with said fixtures are preferably formed of polymeric material such as polycarbonate/ABS, thereby allowing molding of fixture housings with most of the structural elements necessary to produce the functions of the fixture being integrally formed with the housing, these molded structural elements and other structure contained within said housings being located within the housings in a manner whereby the structural elements combine to produce synergistic effects in addition to the primary functions of the structural elements, the fixtures being totally integrated as to structure and function as well as being substantially integral in construction. In particular, a variety of unit fixture housings of differing size and conformation can be formed with substantially circular openings of a size which will accept and receive for mounting within the opening a lamp assembly according to the invention, it thus being possible to configure the lamp assemblies in a consistent manner as to structure and function so that the lamp assembly can be employed with unit fixtures of differing sizes and structural design. 
     U.S. Pat. No. 5,797,673, to Logan et al, describes lighting assemblies for use with a combination lighting unit/exit sign or with lighting unit fixtures wherein lamps are mounted by lampholders capable of swiveling and other motion to provide a substantial degree of freedom for lamping used with a “combination” fixture or with emergency unit fixtures. The lamp assemblies of this invention can be used with the “combination” fixture of this patent. The disclosure of U.S. Pat. No. 5,797,673 is incorporated hereinto by reference. 
     Accordingly, it is an object of the invention to provide a lamp assembly particularly intended for use with an industrial emergency unit fixture including fixtures of differing sizes and conformations, the lamp assembly of the invention being capable of movement relative to a housing of any one of said fixtures to facilitate illumination of a desired area in the vicinity of the unit fixture. 
     It is another object of the invention to provide a lamp assembly usable for producing illumination when in use with an emergency unit fixture, the lamp assembly being configured to provide flexibility in delivery of illumination to a desired area through adjustment of the light beam emanating from said lamp assembly between differing beam widths. 
     It is a further object of the invention to provide an emergency unit fixture particularly intended for use in an industrial environment and with lamping carried by a lamp assembly mounted on exterior portions of the fixture, at least one of the lamp assemblies being carried by the unit fixture and being displaceable by a swivel mounting arrangement as well as along a track formed integrally with said assembly to provide an extraordinary range of movement of lamping within a compact profile. 
     Further objects and advantages of the invention will become more readily apparent in light of the following detailed description of the preferred embodiments. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of an industrial emergency unit fixture illustrating the location of lamp assemblies according to the invention mounted to a housing comprising said fixtures; 
     FIG. 2 is a plan view of the fixture of FIG. 1; 
     FIG. 3 is an elevational view of the fixture of FIG. 1; 
     FIG. 4 is an exploded assembly view of the fixture of FIG. 1 illustrating a single lamp assembly shown in an exploded relationship to the housing of the fixture and with a location on the housing of the unit fixture suitable for receiving a second lamp assembly having no lamp assembly in place; 
     FIG. 5 is a perspective view of a portion of a housing of an industrial emergency unit fixture of larger size than the fixture shown in FIGS. 1 through 4 and illustrating the location of mounting of lamp assemblies configured according to the invention; 
     FIG. 6 is an exploded view of a lamp assembly configured according to the invention; 
     FIG. 7 is a section of an assembled lamp assembly configured according to the invention shown in a narrow beam mode; 
     FIG. 8 is a perspective in section of the lamp assembly of the invention shown in a wide beam mode; 
     FIG. 9 is a perspective view of a lamp assembly of the invention shown at a full limit of travel along integral tracks; 
     FIG. 10 is a perspective view illustrating a detail of mounting of an alternative bracket arrangement; 
     FIGS. 11 a - 11   d  are views illustrating the structure of the bezel element of the lamp assembly; 
     FIGS. 12 a - 12   d  are views illustrating the structure of the reflector element of the lamp assembly; 
     FIGS. 13 a - 13   d  are views illustrating the structure of the housing element of the lamp assembly; 
     FIGS. 14 a - 14   d  are views illustrating the structure of the mounting element of the lamp assembly; and, 
     FIG. 15 illustrates a sealed beam embodiment of the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings and particularly to FIGS. 1 through 4, an industrial emergency unit fixture is seen at  10 , this fixture  10  being mountable to structure generally available in an industrial environment as is disclosed in co-pending U.S. patent application Ser. No. 09/298,305 entitled “Universal Mounting Device for Industrial Emergency Unit Fixtures”, filed Apr. 23, 1999, and assigned to the present assignee, the disclosure of which patent application is incorporated hereinto by reference. The unit fixture  10  is seen to be comprised of a housing  12  formed of a cover  14  and a base  16  which are hinged together. The housing  12  carries within its interior the circuitry (not shown) and similar elements necessary to production of the function of the fixture  10 . In particular, a source of electrical power such as batteries (not shown) is carried within the housing  12  preferably at lower portions thereof The nature of and the operation of those elements carried within the housing  12  can be essentially conventional and form no particular part of this invention. However, it is to be understood that the power supply typically located within the housing  12  is operatively connected to one or more lamp assemblies  18  to energize lamping  20  (first shown in FIG.  6 ), energization of the lamping  20  being substantially conventional and typically accomplished through wiring such as wiring  44  seen in FIGS. 6 and 7 between the power source (not shown) and the lamping  20 . 
     In operation, the fixture  10  is understood to be mounted, typically in an overhead location, so that beams of light can be directed from the lamp assemblies  18  to illuminate particular locations within an area proximate to the fixture  10 . After installation of the fixture  10 , the direction in which the lamp assemblies  18  are turned is a matter of choice depending upon the exigencies of the installation, it being only necessary to grasp the lamp assembly  18  such as by holding bezel  22  to swivel the lamp assembly  18  in a desired direction and to move the lamp assembly  18  along an internal track (not shown in FIGS. 1 through 4) to cause the lamp assembly  18  to direct light in a desired direction. Further, in the preferred embodiment of FIGS. 1 through 14, the bezel  22  can be rotated to produce an “infinitely” adjustable beam width in the range between a pre-set wide beam adjustment position and a pre-set narrow beam adjustment position as will be described hereinafter. Accordingly, the beam width characteristics of the light emanating from the respective lamp assemblies  18  can be adjusted as to beam width. The bezel  22  is provided with knurls  24  which facilitate grasping of the bezel  22 . The bezel  22  further mounts lens  26  which can be provided with indicia  28  thereon to denote the direction of rotation of the bezel  22  necessary to produce a narrow beam as indicated by a small diameter circle and a wide beam as indicated by a larger diameter circle. 
     As can generally be seen in FIGS. 1 through 3, the bezel  22  is mounted to lamp assembly housing  30 , the housing  30  mounting the bezel  22  for rotary movement thereon between spaced limits as will be described hereinafter. The lamp assembly housing  30  is then in turn mounted for movement along a track arrangement (not shown in FIGS. 1 through 3) for movement between limited positions relative to a swivel plate  32  which is received for swiveling movement within an enlarged aperture  34  such as is seen to be formed in the cover  14  illustrated in FIG.  4 . The swivel plate  32  is formed as a spherical segment which is concentric with a substantially spherical rear wall  36  of the lamp assembly housing  30 , the spherically shaped rear wall of the housing  30  essentially being received into the concentrically formed spherical concavity of the swivel plate  32  as will be described in greater detail hereinafter relative to those drawing figures which illustrate in greater detail the structure of the swivel plate  32  inter alia. The degree of movement afforded to the lamp assemblies  18  by the structure thus alluded to allows ready positioning of the lamp assemblies  18  in order to direct light forwardly, downwardly and to the sides of the fixture  10  in order to produce a desired level of illumination at a desired location within an environmental space such as an industrial space under emergency conditions. 
     Referring now to FIG. 5, a housing cover  38  is shown separately from remaining portions of an emergency unit fixture which is of a larger size than the fixture  10  seen in FIGS. 1 through 4 and is of a differing conformation. The housing cover  38  is shown as an example of the differing sizes and conformations of emergency unit fixtures which can be fitted with the lamp assemblies  18  of the invention, it being seen in FIG. 5 that an aperture  40  is provided in the cover  38  which is of a diameter essentially identical to that of the aperture  34  formed in the cover  14  of the housing  12 . One of the lamp assemblies  18  is fitted into the aperture  40  of the cover  38  in a manner identical to the fitting of one of the lamp assemblies  18  into the aperture  34  of the fixture  10 . Whether carried by an emergency unit fixture such as the fixture  10  or a fixture having the housing cover  38  as a portion thereof, the lamp assemblies  18  exhibit essentially the same degree of movement and find essentially the same utility. The lamp assembly  18  can therefore be seen to be usable in light fixtures of various description without departing from the intended scope of the invention. 
     Referring now to FIGS. 4,  6  and  11  through  14 , the structure of the various elements forming any one of the lamp assemblies  18  can be understood. The swivel plate  32 , seen particularly in FIGS. 14 a  through  14   d  as well as in the exploded views of FIGS. 4 and 6, is concavely formed as aforesaid and has an aperture  42  formed therein to receive electrical wiring  44  therethrough as is best seen in FIG. 14 a . The wiring  44  connects at its free end as best seen in FIG. 6 to a standard lamp mount  46  which mounts the lamping  20 , the lamping  20  being a bulb of conventional design. The lamp mount  46  is physically connected to a metal bracket  48  which can include a friction loop clamp  50  which fits over a substantially rectangular mounting plate  52  (see FIG. 13 c ) for mounting the lamping  20  to the interior of the housing  30  and centrally therewithin. The clamp  50  is optional and the bracket  48  can be directly mounted such as by a screw (not shown) to other structure. The other end of the wiring  44  extends into the interior of the housing  12  and connects to a source of power for energization of the lamping  20  as determined by circuitry (not shown) which comprises a part of the fixture  10 . 
     The swivel plate  32  fits into the aperture  34  formed in the housing  12  by means of a mounting tab  54  which is received into the aperture  34  with spaced ramps  56  essentially disposed on the other side of the swivel plate  32  being then received into the aperture  34  with the swivel plate  32  then being displaced into the aperture  34  with the ramps  56  following the contours of portions of the aperture  34  to cause edge portions of the cover  14  defining the aperture  34  to be received into arcuate slots  58  formed one each in each one of the ramps  56  to securely mount the swivel plate  32  in the aperture  34  with a peripheral rim  60  acting to provide a “finishing” flange about the aperture  34 . The curvature of the ramps  56  essentially comprise circular arcs having a radius which is slightly less than the radius of substantially circular swivel plate  32  at free ends of the ramps  56 . The radii of the ramps  56  at inwardly disposed portions nearmost the slots  58  are essentially identical to the radius of the rim  60  in order to allow a secure snap-fitting of the swivel plate  32  in place in the aperture  34 . 
     The concave face of the swivel plate  32  is provided with a pair of inwardly directed, ridge-like track following tabs  62  mounted apart by one/half radian or approximately ¼ of the circumference of the swivel plate  32 , the tabs  62  being integrally formed in concave face  64  of the plate  32 . The tabs  62  are angled from a radius drawn to either end of the tabs  62 . The tabs  62  fit into trough-like tracks  66  formed over at least a portion of the spherical rear wall of the lamp assembly housing  30 , the tabs  62  being shaped to move within said tracks  66  to allow the housing  30  to move in an arc along a substantially radial direction relative to the swivel plate  32 . The tracks  66  essentially comprise arcuate grooves. Movement of the housing  30  relative to the swivel plate  32  is limited by a stop  68  formed essentially equidistantly between the tabs  62 , the stop  68  essentially comprising a substantially rectangular wall-like element, the body of which wall-like element lies in a plane parallel to that chord of the circular swivel plate  32  formed by connecting the ends of the tabs  62  which intersect that circle defining the swivel plate  32 . 
     The stop  68  is preferably integrally formed on the concave face  64  of the swivel plate  32 . The stop  68  abuts against a depressible tongue  70  which is integrally formed in the rear spherical wall  36  of the housing  30  essentially equidistantly between the tracks  66 . The tongue  70  is essentially rectangular in conformation and surmounts a slot  72  formed in the wall  36  of the housing  30 , the tongue  70  being depressible into the slot  72  to facilitate initial mounting of the housing  30  to the swivel plate  32 . Abutment of the stop  68  of the swivel plate  32  against the free end of the tongue  70  prevents further relative movement in the direction of the tongue  70  between the swivel plate  32  and the lamp assembly housing  30 . An arcuate and elongated trough  74  formed centrally in the rear spherical wall  36  of the housing  30  and in alignment with the longitudinal axis of the tongue  70  allows the stop  68  of the swivel plate  32  to move therealong and thus allows the housing  30  to move relative to the swivel plate  32  as the track-following tabs  62  of the plate  32  move within the tracks  66  of the housing  30 . 
     The lamp assembly housing  30  can also be further seen in FIGS. 4,  6  and  13   a - 13   d  to be formed with a cylindrical body portion  31  which is open at one end and enclosed at its other end by the rear spherical wall  36 . Exterior walls of the cylindrical body portion  31  have three arcuate ramps  76  formed thereon and preferably integrally therewith, each of the ramps  76  being approximately ⅓ the circumference of the geometrical base of the cylindrical body portion  31 . Each of the ramps  76  begins at rim  78  of the open end of the housing  30  and extend downwardly essentially in the manner of a screw thread toward the rear of the housing  30  with each ramp terminating at a location of approximately one-half the height of the cylinder defined by the cylindrical body portion  31 . Each ramp  76 , therefore, essentially begins at the rim  78  at a location essentially “above” the termination of an adjacent ramp  76 . Each ramp  76  is turned inwardly at its outermost end to form a stop tab  80  at the rim  78 , the stop  80  preventing further “outward” movement of the bezel  22  relative to the lamp assembly housing  30 , this position being the “narrow” beam position. A U-shaped stop  82  is provided at the ends of each of the ramps  76  at the other ends thereof, the stops  82  functioning to limit rotation of the bezel  22  on the housing  30  at the point where adjustment to wide beam is provided. Yokes  83  of the stops  82  provide ledges on which the bezel  22  rests at the “wide” beam position or in the embodiment of FIG.  15 . 
     The ramps  76  receive the bezel  22  onto the housing  30  as will be described hereinafter to allow the bezel  22  to effectively be “screwed” onto the housing  30  much in the way that a lid of a jar is screwed onto “screw threads” of the jar itself. In essence, the arcuate ramps  76  form screw threads on the cylindrical body portion  31  of the lamp assembly housing  30 , each of the ramps  76  allowing a displacement of approximately ⅜ inch of the bezel  22  onto the housing  30 . 
     Considering now the interior structure of the lamp assembly housing  30 , diametrically opposed pairs of projections  84  are integrally formed with the housing  30  and extend substantially along the full height of the cylindrical body portion  31  before terminating into inner wall surfaces of the rear spherical wall  36 . The projections  84  index a portion of sealed beam lamp  152  (see FIG. 15) to maintain a horizontal orientation of the asymmetrical light distribution of the lamp  152 . Arcuate projections  86  spaced one each on either side of the inner wall surface of the housing  30  comprise that structure in relief which effectively form the tracks  66  referred to hereinabove. Similarly, the reverse side of the trough  74  is seen at  88 . Extending from the reverse side  88  of the trough  74  is the mounting plate  52  which receives the friction clamp  50  associated with mounting of the lamp mount  46  as referred to hereinabove. Four pairs of nibs  90  form an effective plane upon which lower portions of a coiled spring  92  sit, the coiled spring  92  also being held in place by four opposed tabs  94  which have inward projections for engaging the spring  92 . The spring  92 , as also can be seen in FIG. 7, is received over the tamping  20  and against upper surfaces of the nibs  90  as well as against a yoke portion of the bracket  48 , an upper end of the coil spring  92  biasing against an innermost portion of a reflector  96 . The reflector  96  has a central aperture  97  formed therein for receiving the lamping  20  therethrough. The coil spring  92  is held in tension between the supporting nibs  90  and the underside of the reflector  96 . 
     The reflector  96  is essentially seen to be formed of an elliptical body portion  98  having a peripheral flange  100  defined outwardly by a rim  102  which turns outwardly of the reflector  96  to form an outwardly directed circular flange  104 . At spaced intervals about the flange  104 , reflector tabs  106  are spaced apart one-third of the circumference of the circle defined by the flange  104 . The tabs  106  are substantially U-shaped in conformation with the yoke portions thereof extending outwardly of the reflector with an outward leg  108  of each tab  106  extending back inwardly toward the interior of the housing  30  on assembly as is seen in FIG. 7 in particular. 
     The lens  26  is formed of a transparent material such as polycarbonate and is formed with an inwardly directed flange  110  which joins to the periphery of the lens  26  by means of a rim  112 . Peripheral edge  114  of the flange  110  fits against outwardly disposed surfaces of the peripheral flange  100  of the reflector  96  and effectively rests thereon. The assembly comprising the lens  26  and the reflector  96  is received into the bezel  22  from rearwardly thereof with spaced slots  116  being formed in rim  23  of the bezel  22  for ventilation. The slots  116  are spaced equidistantly from each other about the circular rim  23  and the slots  116  surmount indentations  122  formed in inner wall surfaces of cylindrical body portion  120  comprising the bezel  22 . The indentations  122  extend to an inner peripheral edge  124  and are terminated by tabs  126  which extend inwardly of the peripheral edge  124 . 
     The tabs  126  also fit against and move along the ramps  76  of the housing  30  to allow the bezel  22  to be rotated relative to the housing  30  to either draw the bezel  122  onto the housing  30  or to cause relative outward movement therebetween. In other words, the bezel  22  can be rotated in one direction to compress the coil spring  92  and therefore move the lamping  20  further away from reflective elliptical surfaces of the reflector  96 , thereby providing a full wide beam adjustment. Accordingly, the coil spring  92  is essentially fully compressed by movement of the reflector  96  to compress said coil spring  92  through rotation of the bezel  22  in one direction. Opposite rotation of the bezel  22  relieves tension on the coil spring  92  and causes elliptical reflective surfaces of the reflector  96  to be positioned more closely to the lamping  20 , thereby providing a beam which is a full narrow beam adjustment according to the capability of the structure, the narrow beam adjustment being seen in FIG. 7 wherein the coil spring  92  is at its full permitted extension. Rotation of the bezel  22  can be stopped at any location between essentially full compression of the coil spring  92  as seen in FIG.  8  and full permitted extension of the coil spring  92  as seen in FIG.  7 . The stops  82  limit rotation of the bezel  22  at the position shown in FIG. 8 while the stops  80  limit rotation of the bezel  22  at the permitted full extension of the coil spring  92  as shown at the narrow beam adjustment position of FIG.  7 . Friction existing in the mechanism providing the ability to adjust between narrow and wide beam widths allows adjustment to beam widths between the two extremes. In the absence of sufficient friction, additional frictional capability can be provided by material choice or application of a material having a high frictional coefficient over appropriate portions of the structure described. Stops (not shown) can be provided to cause defined beam adjustment positions to be present in the assembly  18  as an option. 
     Completing the structure of the bezel  22 , the rim  118  is seen to be formed by a flange  128  and an inwardly directed rim  130  which terminates the flange  128 , the rim  130  defining the aperture of the lamp assembly  18  through which light is directed. The slots  116  are seen to be primarily formed in the flange  128 . Yoke portions of the reflector tabs  106  fit into arcuate spaces or tracks defined by the flange  128  and the rim  130 , the tabs  106  being maintained in said spaces to capture the lens  26  and the reflector  96  in place within and relative to the bezel  22 . 
     The structure of the lamp assembly  18  provides for an optimized degree of freedom while allowing a low profile due to the effective extension of at least portions of the rear spherical wall  36  of the housing  30  effectively into the interior of the housing  12 . The lamp assembly  18  is therefore compact volumetrically while being adjustable in position over a wide range of motion and further allows for beam adjustment as described in detail herein. The relatively compact structure of the lamp assembly  18  coupled with formation from high impact “plastic” materials causes the assembly  18  to be able to withstand the abuse expected in an industrial environment. Mounting of the lamp assembly into an opening formed directly in the fixture housing  12  contributes substantially to the low profile characteristic of the lamp assembly  18  and the concomitant ability of said assembly  18  to withstand abuse in an industrial environment. 
     Referring now to FIG. 10, an alternate manner of configuring the metal bracket  48  is shown. Essentially, a strip  49  of metal is shown as being mounted by a screw  51 , the screw  51  being received into the top end of a post  53  which is also seen in FIG. 14 b , the post  53  not being shown in figures other than FIGS. 10 and 14 b.    
     Referring now to FIG. 15, a sealed beam lamp embodiment of the invention is seen generally at  150 . The sealed beam lamp embodiment of the invention is seen to be identical to the lamp assembly  18  with the exception that sealed beam lamp  152  is substituted for the lens  26 , the reflector  96  and the lamping  20  of the embodiment of FIGS. 1 through 14. Additionally, the coil spring  92  is not employed since the sealed beam lamp embodiment  150  does not provide adjustment of beam width due to the fixed optics of the sealed beam lamp  152 . Lamp assembly  154  utilizing the sealed beam lamp  152  continues use of the swivel plate  32 , the lamp assembly housing  30  and the bezel  22 , the sealed beam lamp  152  being held between and within the bezel  22  and the lamp assembly housing  30 , the bezel  22  being tightened onto the lamp assembly housing  30  to the greatest degree possible. The lamp assembly  154  remains capable of all movement which the lamp assembly  18  is capable. Use of the sealed beam lamp  152  allows use of higher wattages in an industrial emergency lighting unit fixture such as the fixture  10 . 
     Particular embodiments of the invention have been described hereinabove in relation to illustrations of preferred emergency unit fixtures. However, it is to be understood that the invention can be embodied other than as is described and shown herein. In particular, the lamp assemblies  18  and  154  of the invention can be formed in cooperative relation with housing structure other than that shown. Accordingly, the scope of the invention is defined by the recitation of the appended claims.