US 1508184 A
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Description (OCR text may contain errors)
Sept. 9 1924. 1,508,184
I w. HARRISON LIGHTING FIXTURE Filed Jan. 8 1921 JAZSZENQUR. may HARHZSQN,
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Application filed il'auuary a, rear. no. senses.
To all whom it may concern:
Be it known that I, WARD HARRIsoN, a citizen of the United States, residin at Cleveland, in the county of Cuyahoga, tote of Ohio, have invented certain new and useful Improvements in. Lighting Fixtures, of which the following is a specification.
My invention relates to lighting units and more particularly to units for semiindirect lighting.
The lighting unit disclosed in this application is an improvement on the lighting unit disclosed in.my aplicetion, Serial No. 360,774, filed February 2 1920. My object is to secure the advantages of semi-indirect lighting, that is, illumination in which the reater part ofthe lightin comes from arge expansive ceilings, wit out its recognized disadvanta es. The usual way of securing indirect ilumination is to suspend an open bowl of opal or translucent glass below the ceiling and to place therein clear bulb incandescent lamps. One disadvantage of this method is that dust collects rapidly in the open bowl and on the exposed lamps and seriously interferes with.
the efficiency of the unit. Another disadvantage is that with the concentrated filaments now commonly used in incandescent lamps, the edge of the bowl throws a shar shadow on the ceiling or on the high si e walls and undersirable shadows of the chains or other supports for the fixture a-ppear which detracts from the appearance of the installation. In previous endeavors to eliminate shadows a eat sacrifice in the efiiciency of the unit as resulted.
In my application, Serial No. 360,774, I
have disclosed a semi-indirect unit whichis dust roof and from which the disageeable cei ing shadows have been excluded.
That unit is made dust totally enclosin glass glo ed by a cap. The upper surface or neck of that globe is of clear glass but of a steep roof by using a.
slo'pe' so that the dust can slide ofi', and this surface is" the only exposed surface which can be materially aii'ected by dust accumulations, the incandescent lamp be ng enclosed and the bowl of the globe enameled ight rays eficiency is further increased by using an opal cap over the bowl of the lamp to re fiect the light upwardly through the clear which is coverglass neck of the globe. That unit is made shadowless by fringing oii' the enameled surface of the bowl into the clear glass oi the neck of the globe and by making the ceiling pan of the'unit proportional to the cap which. is laced over the globe. Glare s ellmma'ced TOM the previous unit my invention by constructing the upper portionor neck of the globe ofsuch curvature that rays of light which strike the curved sur face are reflected back into the enameled bowl ofthe globe instead of being reflected outinto the room. i
In a .unit embodying my invention which is the basis of this application, I have pro vided a globe of more pleasing outline. As before, t e bowl of the lobe is covered with enamel which is fringe ofi onto thetrans parent neck of the globe. globe is of such curvature that li, ,ht ra are reflected back into the eyes 0 an o i server.v In order to prevent this, I have provided a difi'using shield of such shape and so positioned that light rays which strike the neck curvature are reflected to the shield which directs the light down ward into the bowl of the globe and so prevents the rays from passing outwardly through the c ear glass portion of the globe and into the eyes of an observer.
Other advanta es and objects of my present invention wili be more fully ex leaned in the following specification und in 1''. 1e accompanying drawin in which Fig. 1 is a front elevation artialy in section of e lighting unit emho ying my invention and 2 is a front elevationof a modification thereof.
In this unit, the cap 10 is fastened to the I I The neck of the lamp 16 is supported in the globe 1.4.. by a socket l7 whic is attached to the wiring coniduit 18 which in turn is attached to a plate 19 soldered to the o lindrical column 11.
The bowl 20 oft 1e globe 14 is enameled to serveas a partial reflector and a care translucent by transmitted light. -1e neck 21 of the obe 1% is clear to permit an unobstructe transmission of the light from the 16 to the cfilllfli. 'i..he zone 223 between is he lam the iiowl and the nee enameled so ti enamel shades of? or fringes oil 15min bowl to the neck for the purpose or venting s shsr coin.
tho light the howl iion Scrisl. l lo. i 5 tionecl.
' The bowl is s stccgs to prevent, as cumulstion ihsrson of oust which tones to sliclo off so that she unit is but little sffectsci 510. thcrcby. is obvious of course no clus; can swim: she unit. "llhc incsi'idcsccnl lamp 16 as previously ststctl, is howl-onsmclccl which 1110135315 "c -3 bowl tho "lamp is coated wih an enamel. which pmis msrily reflects majority of the l 'ht i'sys "incident thereon hut allows as small poi'tion to hotian'sinittszl. j y moons of i'ciieciing the Insjor nor 'on tho light upwardly fnom the howl ()1 ill mp, such as s rcfieciw so ing mos-11s surrounding a portion of the bowl of cho lamp, may used. in this wsy Lhc amount of light thsl; falls upon the bowl 20 of the globe i4 is comparatively small and decorative lcsigns gilscsal on tho cnaincled bowl are pleasingly lighted out not; to on in- "tcnsi'ty detrimental to the opsicnl perception of the design In order to pa'cvsnt ii ht rays such as the my AB, which passes 1E1. om the light sourcc A to the point B on the nah of the giohc from being; rcilcctco om the neck along shc lino Bflpassing through the neck. of the lamp l6 aml the gloss neck :21 of also globe and so into the eyes of an ohscrvcr, 2i dcliccting shield 24: is placed around the neck of the lamp 16 5nd extends upwardly and. oufi- -War ly until 'lfnstcncd to the cap 10. The effect of the shielrl 9A: is to intercept such rays, the my BC being inlcrcepsccl, for instance, at l) on the surface of the shield 2 The my ED is then dcl'lsctecl downward along thc line DE the enameled. howl app ico gn'cviousiy nzsin allow busneck 2].
ss possisls, the s. M
90 of the. Jobs. Thus no light is permitted. to pass oirccizly iron: the glob-e toward, the oi observer without being properly disused,
As disclosed in my application, Serial No. 860,774, picviousiy mentioned, the ceiling is of such size that light which passes from the concentrates filament A of llllfifi lamp 16 throws the shsdow of the cap 10 up on the ceiling" pan l2 and. substantially covering is. The eilccl; is to cause the contrast between the lighted ceiling and the shadow cast by the cap 10 to be lost in the natural contrast between the lighted ceiling and the ceiling pan which is ordinarily constructed of comparatively (lurk material" in 2 is shown a modification of a light unit embodying my invention in which the cap 25 is att'schcd to the ceiling pan 26 by means of a. chain 27, the relative; PIOPOI'lLiOIl oi? the cap 25 to the ceiling psn 26 hcing iaintsincd. as before.
l /"list I claim as new and desire to secure Lcitcrs Potent of the United States, is
in lighting unit, the combination with an incsmlcscenslainp and a, supper therefor, of a globe totally inclosing said lampand comprising s substantially disc-shaped lower non-transparent bowl portion and s sulistuntinlly oonicsl upper transparent neck ortion, and s deflecting shield interposed Jets/con the neck portions of said lamp and of said globe, said parts being so proportioned and arranged that substantially all light; rays reflected from one side of the neck portion of the globe towurclihc opposite siolc Will encounter said shield and'be dcflcctcd into the bowl portion ofsaid globe.
In witness whereof, I have hereunto set my hand this 30 day of December, 1920.