US2778929A - Luminaire - Google Patents

Description

R. W. LOEHR Jan. 22, 1957 LUMINAIRE C' Sheets-Sheet 1 Filed Dec. 51, 1952 R. W. LOEHR Jan. 22, 1957 LUMINIXIRE 5 Sheets-Sheet 2 Filed Dec. 31, 1952 INVENTOR Robert W. Loehr.

WITNESSES:

LUMINAIRE RbertW. Loeh'r; Lakewood, Ohio, assignor towestinghouse Electi'icC0rporation, Eastlittsburgh, Pa., a corporation1of Pennsylvania= Application Decemben3l; 1952, Seral No. 328,958

5 Glims." (Cl. 240-251 Tlis vention relates"generallytoli1minaires and more partieulrly-to areflector type of luminaire whch employsan =elngatedlight source.

While lmirraires efthis general type havebeen used in the past, theyhave been relatively complex in form,- and/orthe reflectors used have been of reltively simple and regular form; Th is hasresultedinahighrelative cest of= manufcture er in many cases a relativelylew reflector effiiency, and a reltively large over-all luminaiiesthlctre.

Oiie object ofthis-iirvention, therefore, is te provide a luminaire with anovel unitary reflector construetion having a high=ligiit utilization=efliciency.

A-notlier objct of=thiS inventien is te -providea luminaire ofthetypedescribed*havirig a nevel reflector censtructonproviding a high reflector efficiency.

Still another object of tl1isdnvention-is to provide a simplifid form of lminaire for street lighting or the like=service; empleying an elongated high intnsitylight sourceiman-eflcient manner, while keeping the size of the luminaire at a minimum.

Amore specifieobject ofthis inventien isto provide a luminaire of generally ovate form having a unitary housing andmounting portion, and a unitary reflector eentainedtherein cernprising a pluralityof differently shaped portions for efiiciently directing reflectecl light in a pre determined mannen These and other objectsof thisinventon will become more apparent" upon:consideration of the; followingcletailed. description: of. a preferred embodiment: thereof, when taken in connectien with the attnched drawings.in

whch:

Figuret 1. is a side elevationview of aluminaire con structed. in; accordance; With this inveniion; With certain.

of the parts shown in secton.

Big: 2 is a transverse cress-section view of the luminaire;shown in Fig. 1, and taken substantially en the line II+II.O;Fg. 1; and

Fig. 3. isa.bottom-plan view of the lurninaireshown in.Fig;1,with the;refracterbowl removed.

While the: invention is :herein. specifically disclosed as embodied in astreetzlighting type ofluminaireit shoulcl: be. understoodatthe outset thatthe nvention in its variousaspectsmay findapplicatien in:other types of luminaires than;thatspecifically, hereindisclosed, and consequently the following specific disclosure is not intended as;limiting;with respect toany ofthe features of this in vention.

The luminaireshown on the drawings is depicted as having-a hosing 2 which is generally ovate in form, being provdedwith a botternopening so. that it formsn effect onehalfof an ovate-spheroid. The housing 2 is formed of one integral piece of. material preferably a single metal casting, such fo1 example as aluminum..er an alnminum alloy. The housing 2has integral therewith at one end a meunting sleeve 4 which is acl'apted tereceive Unitcd Statcs Patent a monnting bracket, and is provided with epposed set 2778,929 Patented Jan. 22, 1957 ice 2; screws for engagingthebracket; and adjusting thepesi tionof theli1minaiie thereen; A U-bolt8 is mounted tobe movableina slot 10 -provided in thelower Portion of mountingsleeve 4 ofthe housing, and is ad apted tebe drawnupinto clamp ing engagement With the mounting bracket when inserted irrthe m0unting sleeve 4, tofinnly secure the housin g 2 en -any such bracket.

The heusing 2 has alsoformed integrally iherewth a pair of l'ongitudinallyextendingreinforcing ribs 12, whch extend generally longitdinally from the meunting slee"e 4 of theheusing, overthemajor partof thelength ofthe housing in divergent relatin. thehousing 2 isprovided with anoutwardly extending integral flange 14 whch has"adownwardly extending 1ip,

16- at its outer end: A portionof the flange l4 at one side of the housing is offset asat8, for a purpose tobe described. At the end of the housing 2 epposite the mounting sleeve 4, there are provided spaced outwarclly extendingears20, alsofor a purpose whch willbe hereinafterdescribed.

A; reflecton22 is adapted te be meunted within the heusing;2 and: is formed of one piece. of sheet materiah 2nd while. generally of the same form as the housing 2, it ditfermspecifically indetails of formas willbe herein after dcscribed:. Preferably thereflector 22 is stamped from a single: sheet oftmetal:whichis capable of being providedwithgoodreflectirig characteristics, such as alu minum sheet which1can be polished end/er anedized to provide er goed reflectingsurface. The housing 2 has a plurality of spaced, integral supporting besses 24 depending.from the innersurface thereof, and these studs are internallythreacledor receiving screws 26 ter mounting the reflector 22 in eperative positien in the.housing.

There may also be meunted in the housing 2. for the luminaire, between; the reflector 22 and the mounting sleeve 4;a terminal hlocl 32 supported on a pair of projectiens 28 and 30:integral With; the. housing 2, and at least oneof whch; is threaded for receiving a mounting screw 31 te secure:theterminal bleek 32 in postion. In the same generallocatien within the housing 2, there is also providetl a supporting:projection 34 integral with the topwall of the housing.2; whch has a tappecl openingforreceiving a monnting screw 38 ter anemgled supporting bracket 36. The supperting bracket 36 when mounted in operativepositon has-its ether leg extendng vertically for mounting thereon a lamp secket 40, ter ex ample as by screws. 41 engaging the lamp socket and adapted te bemounted in a lower set of openings in the vertical arm of thesupperting bracket 36. The lamp secket 40 is herein illustrated as being of the screw oase type forreceiving a lamp 46 havingn screwbase. The

lamp 46 is illustratedas being elongated in ferm and is preferably of the high intensity mercury type. The partieular lamp 46 llustrated:when mounted in the lamp socket 40 lies substantially on the longitudinal center line of the housing2 and reflector-2.2, at er slightly above the lower edge of the refleetor 22. The meunting eracltet 36= for the lamp socket 40 is capaele of adjusment te accon modate a lamp havng a .greater distance bctween ts base and the:.midpoint of its lumineus column. 1nus, the top inclned leg of the mountingbracket 36 is provided With a second opening 44for receiving the mounting screw 38. te thus position the vertical leg of the mounting bracket closer te themounting sle eve 4 of the heusing 2. At the same time, in order to accomrneclate the thus lowered.postion of thevertcal leg of the mounting bracket 36, this legis .providecl with additional openings 42 fer receiving the.mounting.serews 41 en .the lamp secket 49 As p reviously mentiened, the lamp 46 is preferably of the highiitensity mercury, type havingan inner tubularl envelpe. 48" of.j a high temperature-resistant transparent= material, such fr example asfused quartz, and having;a

The bottom opening of larger outer envelope 50 of a transparent material, such as glass. In a lamp of this type, the illumination originates, of course, wthin the inner tubular envelope 48. Sometimes this type of lamp may have an inner envelope of a material which is less resistant to high temperatures than quartz, in which case it may be desrable to provide an arc stabilizing magnetic coil 51 which is illustrated as being located transversely of the housing 2 and reflector 22, at the upper portion thereof, being accommodatecl in a transversely extendng slot out in the upper wall of the reflector 22. Such a stabilizing coil 51 is adapted to be connected in series with the lamp and to produce a magnetic Held such that the elongated arc within the lamp is not permitted to bow upwardly into contact with the inner lamp envelope. The coil 51 is preferably covered by a generally cup-shaped cover 49 which may be formed of the same material as reflector 22. Preferably, the lower open bottom of the reflector 22 terminates in a short outwardly turned flange 52.

In most cases, it will be desirable to provide a globe 54 over the bottom opening in the housing 2, with this globe to be made of any desired transparent material, such as glass, and it may be additionally formed with various interior and/or exterior prisms for directing the light rays passing therethrough in the desired pattern. The upper open end of the refractor 54 has an integral outside rib 56 which is adapted to be engaged by a clamping band 58 which surrounds the upper open end of the refractor 54 and has laterally extending apertured ends 59 for receiving a clamping bolt 60 to securely clamp the band 58 to the upper end of the refractor bowl 54.

The refractor bowl 54 is adapted to be releasably supported in closed relation with the bottom opening in the housing 2 by a pvot support at one end adjacent the housng mounting sleeve 4, and comprising a pair of supporting arms 62 provided integral with clarnping band 56 and joined at their outer ends by pvot pin 64 which is adapted to be removably mounted in a hook-shaped support 66 secured to the underside of the housing at the mounting sleeve 4 thereof in any desired manner, such as by mounting screws 68. There is also provided a leaf spring 70 which is secured to the clamping band 58 intermediate the pvot supporting arms 62, and which is engageable with a lip 61 formed integral with the housing.

At the other end of the housng and the refractor bowl, the clamping band 58 for the refractor bowl 54 is providecl with an integral latch projection 72 extending outwardly therefrom for engagement with a movable latch 74, which is generally U-shaped in cross-section. The movable latch 74 is adapted to be mounted on a pvot pin 76 extending between the supporting ears 20 on the housing 2, and is biased in a counter-clockwise direction as viewed in Fig. 1 to latching position by a coil spring 78 mounted on the pvot pin 76 and reacting against the housing and the movable latch 74 at its opposite ends, respectively. The movable latch 74 is also provided with a latch reset roller 80 mounted on a pin connecting the sides thereof, and with an ntegral latch projection 82 also locatcd between the sides thereof, preferably formed with transverse riclges 84 on the upper side thereof. If desired, a light shield 86 of opaque material, such as aluminum or the like, may be inserted in the refractor and held tberein in any suitable way, such 215 by a frictional fit, toward the end of the refractor and housing 2 having the mounting sleeve 4 on the housing.

T he refractor bowl 54 is illustrated in Fig. 1 as being latched in position where its upper rim is in engagement with a sealing gasket 87, which in turn engages the lower flange 14 of the. housing 2. Preferably the gasket 87 is of a weather-proof material, such as water repellent felt or the like, and is in compressed condition at the closed position of the refractor bowl 54, to exclude the elements from the luminaire, and it will be observed that the downwardly extending lip 16 on the housing flange 14 further acts to protect the seal between the refractor bowl 54 and the housing 2. If it is desired to open the luminaire for lamp replacernent or for cleaning purposes it is merely necessary to release the movable latch member 74 by moving the lower end to the left as viewed in Fig. 1, until its latch projection 82 and reset roller 80 clear the latch projection 72 on the housing. The refractor bowl 54 is then freed so that its pvot pin 64 can drop down to the bottom of the slot in bracket 66 and pvot downwardly about the pvot pin 64. During such downward movement the leaf spring 70, previously referred to, moves up and disengages the lip 61 on the housing. The refractor bowl may then be readily replaced by rotating it a further amount until flat surfaces on arms 62 are at a position to clear screws 68 whereupon the bowl may be rnerely lifted to move its pvot pin 64 out of the slots in support 66 on the housing, and a new bowl inserted in its place. Thereafter, the luminaire may be closed merely by swinging the refractor bowl 54 back to the position shown in Fig. 1, and this results in automatically latching it in closed position, as the latch projection 72 on the refractor bowl will engage the reset roller 80 on the movable latch 74 during closing movement of the refractor bowl, to move the movable latch member 74 in a clockwise directon and to enable the latch projection 72 to slip past the roller and latch projection 82, whereupon the biasing spring 78 for the movable latch member 74 will cause it to move back where its latch projection 82 engages beneath the latch projection 72 on the refractor bowl, to thereby latch it in the closed position shown in Fig. 1 of the drawings. During closing movernent of the bowl, the free end of spring ultimately engages the lip 61 on the housing. Thereafter, pvot pin 64 is lifted in the slots of support 66 While pivotal movernent continues about the free end of spring 70. When the adjacent edge of bowl 54 engages gasket 87, spring 70 is stressed, and the gasket is placed under spring pressure.

Turning now to the reflector 22, it will be observed to consist of a special form for reflecting incident light rays emanating from the lamp 46 in a particularly useful and eflcient manner. Thus, the lower opposite longitudinal sides of the reflector 22 have substantially vertically extending curved portions 88 preferably paraboloidal in form, which extend for substantially the entire length of the lamp. The reflector 22 also has at each side immediately above the portions 88, curved portions 90 which are rather sharply turned inwardly towards each other, and finally, the reflector has at each side curved top p0rt0ns 92 which are rather sharply turned upwardly and towards each other from the intermediate portions 90, to join substantially on the vertical center line of the luminaire. These longitudinal side portions of the reflector 22 are joined at each end by generally smoothly curved end portions.

The purpose of the particular formation of the reflector 22 can be best realized by reference to Fig. 2 of the drawings, wherein reflected ray traces are illustrated. It will be observed that the rays reflected from the lower side portions 88 of the reflector are directed downwardly at a substantial angle above the nadir, illustratively at an angle of 55 to and that these reflected rays pass just below the nner lamp envelope 48 and the point of cut off at the opposite side defined by the lower edge of the reflector, and impinge on the refractor bowl 54 at the opposite side of the luminaire. Intermediate reflector surfaces are designed to direct reflected light rays at a relatively 10W vertical angle, and it will be observed that the ray traces extend downwardly more nearly vertical at the same side of the lamp as the particular intermediate portion 90, and that these rays avoid even the outer envelope 50 of the lamp. It will be notedthat the top ray trace frorn reflector portion 88 and the bottom ray trace frorn reflector portion 92 converge so as to eventually overlap. The upper reflector surfaces 92 are designed to direct reflected rays in a manner to fill in the distribution pattern between the regions provided for by surfaces 88 and 90, and t Will be observed chat these rays are directed trom either reflector surface 92 toward the other side of the reflector and above the inner lamp envelope 43, but are within the cut oi angle defined by the lower edge of the reflector at the opposite side.

It will be noticed that substantially all of the reflected rays are thus within the cut-ofl angle provided by the lower edges of the reflector 22 and housing 2,

and thet the reflector 22 has its lower cdge extending;

belo=v the inner lower edge of the housing 2 and into the reractor bowl 5@ when in operative position. This obviously prevents less of direct light from the 1arnp by absorption by the inner faces of clarnping band 5%. The fact that this particulnr reflector is capable of directiog, all reflected light rays in a marmer to avoid the inner envelope 48 of the lamp prevents absorption of reflected light by the envelope whch rnrnecliately surrounds the light source. Furtherrnore, since a substantial amount of reflected light, in fact all of that reflected from reflectcr portons 9%, and at least 2. portion reflected from the other parts of the reflector 22 avoids even the outer envelope 59 of the lamp, further increases the eflciency of the luminaire The light source is thus provided in en isolated zone through which no reflected light passes, but sueh isolatecl zone is surrounded by multiple zones of reflected light.

As prevously pointed out, it is desired that tln's iriventon be not limitecl to the particular form of luminaire specifically describecl herein, as it will be readily apparent to persons skilled in the art that various changes and modifications may be made in this particular construction without departing from the broad spirit and scope of this iuvention. Thus, the luminaire may have various forms of housing or support, it may be used with or without a refractor, and instead of being symmetrical about any axis, it can be adapted t0 direct the maximum candle power at any precletermined lateral angle with respect to any axis of the support or refractcr. These are illustrative, but not limiting, as to other forms Which this invention might take and of various ether ways in which the invention could be used. Accordingly, it is desired that the inventon be given a broacler scope, and that it be limited only as required by the prior art.

1 claim as my invention:

1. A luminaire c0mprising, an ovate spheroidal housng having an open bottorn, a generally similarly shaped reflector mounted in said housing with its longitudinal axis generally coincdent with the longitudinal axis of said housing, means or supporting an elongated light source generally centrally and longitudinally within said reflector, said reflector being c0rnprised in part of adjoined diflerently shaped longitudinally extending light ray reflecting portons, and each of said light ray reflect ing portons being located with respect to an inserted elongated light source to reflect incident light rays in avoidance thereof and at an angle less than the cut-oi angle of the reflector.

2. A lnrninaire comprising, an ovate spheroidal housing having an open bottom, a generally similarly shaped reflector mounting in said housing with its longitudinal axis generally coincident with the longitudinal axis of said housing, means for supportng an elongated light source generally centrally and longitudnally within said reflector, said reflector being comprised in part of adjoined diflerently shaped longitudinally extendinglight ray reflecting portons, each of said light ray reflecting portons being located with respect to an inserted elongated light source to reflect incident light rays at an an gle less than the cut-ofi angle of the reflector, said light ray reflectng portons includng at least at one side of a vertical plane extending longtudinally through said reflector a lower reflector portion directing reflected light rays to one side of an inserted source, and an upper reflector portion directng reflected light rays to the other side of an inserted source.

3. A lumnaire comprising, an ovate spheroidal housing having an open bottorn, a generally sirnilarly shaped reflector mounted in said housing with its longitudinal axis generally coincident with the longitudinal axis of said housng, means for supporting an elongated light source generally centrally and longitudinally within said reflector, said reflector being comprised in part of adjoined dfi:erently shaped longitudinally extending light ray reflecting portons with each of said light ray reflecting portons being located with respect to an inserted elongated light source to reflect incident light rays at an angle less than the cut-ofi angle of the reflector, said light ray reflecting portons including at least at one side of a vertical plane extending longitudinally through said reflector a lower substantially paraboloidal reflector portion directing reflected light rays at a substantial angle to the nadir towards the other side of said plane and beneath an inserted source, an intermediate reflector portion directing reflected light rays at a relatixely small angle to the nadir at said one side of said plane, and an upper reflector portion directing reflected light rays to the opposite side of said plane.

4. A luminaire comprising, an elongated dished housing having an open bottom, an ovate spheroidal reflector mounted in close relationship within said housing and with its longitudinal axis generally coincident with the longitudinal axis of said housing, means for supporting an elongated light source generally centrally and longitudinally within said reflector, said reflector beng comprised in part of adjoined diflerently shaped longitudinally extending light ray reflecting portons, and each of said light ray reflecting portons being located with respect to an inserted elongated light source to reflect incident light rays in avoidance thereof and at an angle less than the cut-off angle of the reflector.

5. A lumnaire comprising, an elongated dished housing having 2111 open bottom, an ovate spherodal reflector mounted in close relationship within said housing and with its longitudinal axis generally coincident with the longitudinal axis of said housing, means for supporting an elongated light source generally centrally and longi tudnally within said reflector, said reflector being comprised of a plurality of adjoined di1erently shaped longitudinally extending light ray reflecting portons extending longitudnally along each of its sides, said light ray reflecting portons being located with respect to an inserted elongated light source to reflect incident light rays in avoidance thereof and at an angle less than the cut- 0 angle of the reflector, and each side of said reflector having at least two light ray reflecting portons formed to direct reflected light rays to one side of an inserted elongated light source.

References Cted in the file of this patent UNITED STATES PATENTS 1,153,443 Pole Sept. 14, 1915 1,741,965 Yates Dec. 31, 1929 1,753,885 Gerhardt Apr. 8, 1930 2,578,451 Rex Dec. 11, 1951 2,584,671 Cator et al Feb. 5, 1952 2662,165 Franck Dec. 8, 1953 FOREIGN PATENTS 585,561 Great Brtain Feb. 11, 1947

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