US2810823A - Fluorescent lighting fixtures - Google Patents

Description

Oct. 22, 1957 E. F. GUTH, JR

FLUORESCENT LIGHTING FIXTURES Filed June '23. 1954 INVENTOR, EDWIN F. GUTH, JR.

A TTOIZIVE'YS United StatesPatent Ufifice;

2,810,823 Patented Oct. 22, 1957 Ian- FLUORESCENT LIGHTING FIXTURES Edwin F. Guth, Jr., Ladue, Mo., assignor to The Edwin F. Guth Company, St. Louis, Mo., a corporation of Missouri Application June 23, 1954, Serial No. 438,672 8 Claims. (Cl. 240-5111) This invention relates to lighting fixtures, and more particularly, to light-difiusing fixtures for fluorescent lamps.

In cove-lighting, as heretofore practiced, the lamp bulbs are contained in an upwardly-opening built-in trough, which runs about the wall of the room, the bulbs thereby being hidden from view and the illumination being indirect by reflection from the ceiling. This arrangement has not been entirely satisfactory, however, because of the expense in constructing the coves and the difliculty in supplying adequate ventilation. Also, portions of the wall below the fixture and portions of the ceiling remote from the wall are often poorly illuminated.

Accordingly, it is an object of the invention to provide an improved cove-lighting system, and more specifically, to provide a cove-lighting fixture that is inexpensive to manufacture and install, easily maintained, of low brightness, and of high efliciency from the viewpoints of lampoperating temperature and light utilization and distribution. Also, the invention includes among its objects the provision of a fixture of the character described whereby different illuminating efiects may be achieved by selective operation of the bulbs within the fixture.

Additionally, it is not uncommon to encounter lighting problems that require direct illumination from a fixture mounted on a wall, as at the head of a bed, in a fitting room or in a barber shop. Therefore, the invention includes among its objects the provision of a fixture having the advantages above mentioned, but which may also be utilized where a shielded direct type of illumination is desired.

Finally, it may be noted that there are instances where conventional ceiling fixtures are not entirely satisfactory. An indirect or semi-indirect fixture of the type having a reflector (opaque or translucent) presents maintenance and cooling problems, and frequently the distribution of light is not as wide or as uniform as might be desired. On the other hand, the direct type of fixture provides an even more concentrated source of illumination, although the brightness may be somewhat reduced by equipping the fixture with a diffuser. Accordingly, it is also an object of this invention to provide an indirect or semiindirect ceiling fixture, which may be made from units having the advantages previously set forth.

Briefly, these objectives are achieved in a single, multipurpose fixture. When used for cove lighting, the fixture comprises an elongate housing having a generally vertical back and a bottom which is in part formed by a difiusing.

louver, preferably of the open egg-crate type. The top of the fixture is formed by a second relatively larger or primary louver (preferably of the open egg-crate type), which is inclined to extend adjacent and over the bottom louver. Sockets for a pair of fluorescent tubes are mounted in the housing at the ends thereof, the arrangement being such that a first tube is supported within the upper portion of the housing and a second tube is supported in the forward lower portion of the housing over angles in the manner of a channel section.

2 the bottom louver and beneath the inclined louver. The sockets may be supported on angle brackets, and a refiector of angle section extends therebetween, so that one wall of the reflector lies beneath the first tube and another wall thereof lies behind the second lamp.

A direct shielded type of illumination is achieved by inverting the fixture so that the inclined primary louver faces downwardly and outwardly, whereas the secondary louver faces upwardly. A ceiling fixture is readily made by assembling two such units in back-to-back relationship, thereby to provide a pair of inclined louvers facing upwardly and outwardly toward the ceiling.

Other features of the invention will be in part apparent from and in part pointed out in the following detail description taken in connection with the accompanying drawings, in which: 7

Fig. 1 is an oblique detail view of a fluorescent cove lighting fixture embodying the invention, parts being broken away;

Fig. 2 is a front view of the fixture with the primary louver in part broken away;

Fig. 3 is a cross section taken on the line 33 of Fig. 2;

Fig. 4 is an oblique view of the fixture illustrating how it is used to provide shielded direct illumination; and

Fig. 5 is an oblique view showing how two units may be arranged in back-to-back relationship as a ceiling fixture.

Referring to the drawings, there is shown a fixture having a pair of fluorescent lighting tubes 1 and 3. The tubes are contained in an elongate housing having a back 5, a bottom 7 and a relatively narrower top 9. The top and bottom are in part formed from a sheet metal member the parts 7 and 9 projecting from the back 5 at right Panels 11 are secured in telescoping relationship over the ends of this channel section, and the end panels 11 support an elongate hollow member 13 in outwardly spaced relationship from the bottom element 7. This member 13 is shaped as a pocket with a bottom wall 15 which is in coplanar relationship with the bottom 7. A front wall 17 extends upwardly at a forty-five degree angle and a top-forming wall 19 is bent back at right angles to the front 17 to lie at a forty-five degree angle with respect to the bottom of the housing. The elongate member 13 is received within inturned flanges 21 at the front of the end panels. Similar flanges 23 are inturned at the top rear portion of the end panels, and these flanges 23 project forwardly beyond the top part 9 and'have lips 25, which are turned down into coplanar relationship with the top-forming wall 19 at the front of the fixture.

A lower opening is thereby defined between the members 7 and 15, and an upper opening is defined between the elements 9 and 19. These openings extend the length of the fixture, and are adapted to receive louvers 27 and 29, respectively. 7

The louvers are of the open egg-crate type, preferably being formed of translucent plastic material to have small open interstices. This type of louver is described in the copending application Serial No. 261,780, filed December 15, 1951, by Edwin F. Guth, now Patent No. 2,745,001 granted May 8, 1956. More particularly, the louvers have a thickness of about three-eighths inch, the interstices measuring three-eighths inch to the side, and the wall thickness being approximately one-sixteenth inch. The fixture may measure approximately six inches in height and width, its length being determined by the size of fluorescent tube to be utilized.

The lower louver 27 has tapering side portions 31, which seat over the members 7 and 15. Resilient clips 33 and 35 secure the lower louver against displacement a resilient clip 35 1's in V ballast '(not shown). devices 55 aresecured to 61 extending beneath be withdrawn for cleaning or other maintenance operations. The upper louver '29 is secured against inward displacement at its lower edge by the clip 35 and also by,

tabs 37 afiixed to the end walls of the housing. The V the form of a channel 'section, the base portion being 'secured at 39. to the front Wal1'17 of the housing, and the leg portionsdl and 43, respectively, overlying the respective margins 31 and 45 of the louvers 27 and 29. The tabs 37 are located near the top of the fixtureand have legs 47, which extend inwardly as supports for the upper portion of the louver '29. r

It willbe observedthat the louver 29 does not extend entirely to the top 9 of the housing, butit does serveto shield the fluorescent lamp 1, which is mounted in the upper portion of the housing. The other lamp} is mountedin the lower portion of the ;housing, generally 7 over the lower secondary louver 27 and behind the lower portion of the larger primary louver 29. Bridging brackets 49 .aresecuredr at the ends'of the housing by flanges 51, the brackets 49 forming a chamber of rectangular cross' section, which may contain 'the lamp The lamp sockets 53 and starter the brackets, and a reflector 57 extends between the brackets.

form of a, right angular section, with a lower Wall 59 extending behind the lower lamp 3 and an upper wall the upper lamp 1; ,Also,'-a flange the back behind the upperlamp,

63 may be turned up at The reflector is releasably seas illustrated in Fig. 3.

, cured at its. ends to the brackets 49, by means of thumb so that it can readily be taken otf t hrough the nuts 65,

the louver 29 is removed.

top opening left when In cove lighting, are securedin end-to-endirelationship,against the wall near the ceiling of a room. illumination is of the semiindirect type in that a portion (say, twenty percent) of the light is downward through the secondary louver 27, 7 whereas a larger portion (eighty percent) is directed upwardly and outwardly. to the ceiling of the room; This construction oliers an additional advantage when the lamps 1 and 3 are connected iii-independent circuits so that they can be operated separately. S u'choperation is particularly useful in 'auditoriums and the-like. When the upper :lampl disconnected, the level or intensity of the illumination is reduced, and when :only the upper The reflector is in the:

several fixtures of the typedescribed stood that efiicient operation of fluorescent lamps is a critical function of their temperature, hence the necessity for proper ventilation. The accumulation of dust is always a problem with fixtures, and this is particularly so with indirect fixtures'of the type using solid dustcollecting reflectors or difiusors. V

From the foregoing description, it is apparent that those skilled in the art will understand the structure, function and mode of operation of the invention herein disclosed, and appreciate the advantages thereof. Although several embodiments have been disclosed in detail, it is who understood that the invention is not limited thereto, but the drawings and description thereof'are to be understood as being merely illustrative. For example, the'relative areas 'of the primary and secondary fixtures may be ch anged,

and the louver may be entirely closed at its top by extension of the top wall 9 or the louver 29. It isreali zed that many, modifications and variations will present themselves to those skilled in the art without departing from' the spirit of this invention or the scope thereof as set forth in the appended claims,

Having thus described the invention, what is claimed and desired tobe secured by'Letters Patent is;

l, A lightingfixture' comprising an elongate housing, said housing having a generally vertical closed back, a generally horizontal bottom termed at least in part, by

an open egg-crate louver, a .sloping';t,op portion fonned at least in part by an open egg-erate-louver and inclined from the front of thefixture toward said back wall, and

means for mounting L -elongate fluorescent bulbfiin the a space between the two louvers, said space otherwise being unobstructed. I r V V V r 2. A lighting fixturejasset forth in claim 1, including means for supporting :apailfzof elongate fluorescent-bulbs,

' one of said, bulbs. beingdisposed in the upper back portion .of'the housingand the-other bulhbeing disposed in the lower front portion of the housing, said .bottom.egg-

cratelouyer being disposed beneath said second bulb;and 7 said upper :eggac-rate louver extending 'oyergboth of the bulbsv .3. A lighting fixture'as set forthiin claim 2, further 7 including reflector ,Ine'ans extending beneath said first bulb lampjl is operated; .the'leveland characterofillumination are changed substantially. v

The fixture may also be employedas :aqshielded edirect wall-mounted light, as ina fitting IOGIIL, barber shop, .or

.over a hospital bed. "In that :eventgit :-is secured, at its back-'5 against a'wall, but in inverted vrelationship, as

indicated in Fig. 4, so that most of the illumination is directed downwardlyfor high-intensity use, although 1 "some por'tion is directed upwardly for general lighting louverde- J r Referring now t F"g. 5, it 11 be apparent that a and in back .of said second bulb. s t

. 4. A cove lighting luminairefor the wall of a room, v

comprisingian elongate .housing having a closed aback lying against the wall, a generally horizontal bottom 7 which is closed in the region adjacent the back andzothee wise constituted by an open egg-crate louver disposed outwardly iiromthe. wall, .a second relatively largereg crate louver inclined toward the back from adjacent the outer f-ron't {margin of said first louver, and an elongate fluorescent bulb mounted within .:the space between said louvers,-s'aid space otherwisebeing unobstructed.

I '5. A lighting installationas set forthin claim 4, wherein the fixture :has two bulbs, one being disposed above the bottom louver in .the lower portionwof "the housing and the other bulb being disposed inithe 'llpperback portion of the housing, and reflector rn eans extending back of said-first bulband beneath'saidsecond bulb.

pair "of units may be mounted back-to-ba'ck' to provide an o r 7 improved ceiling fixture of the semi-indirect type. -As

*such, the fixture otters-certain advantages over existing systems where problems are presented in achieving wide distribution er the light, adequate ventilation of fthe lamps, lo'w brightness and "varied'ilig'h'ting efiecfs. As indicated previously, operation of lamp 1"results-in indirect lighting, whereas operation "of lamp #3 provides serni-indi'rect lighting =Of reduced intensity, and operation of both'lanips provides semii ndirect'lighting bf increased intensity.

' iThe:openJegg-cratelouvers not-,onlyatfordlowrbrightness, but also insure adequate yentiIationiyof the lamps 7 V and provide for a cleaner operation. It will be under- "6. A shielded direc't lurninaire :for the wall of a room, said luminaire comprising an elongate h'ousingha'ving a generally vertical closed 'back lying against the wall, a; V 7

generally horizontal top'close'd in the region adjacent said back and otherwise] constituted 1 byian open egg crate louver disposed .ou'twardlyjfro'rn thelback, a secondre'la tively .larger .eggcrateglouver sloping downwardly toward the .back..'from adjacent the outer nan margin of said first '.louver,.and ta jfiuoreseentjbulb mounted in the space between saidlouvets, said space otherwise being relatively unobstructed. i V} V. i 1 i 7 -A shieldedidirect vluminaire'as 'set' jforjth inclaim 6, wherein saidhofusing encloses 1W0 bulbs, Qnepf which is mounted beneath the ,i pper'louger ,in'thetrqnt upper portiontof the housing and the other or which isrnounted above said second louver in the lower back portion of the housing.

8. A ceiling luminaire comprising an elongate housing, said housing having a bottom formed by a pair of egg-crate louvers, said bottom louvers being spaced from one another and the space therebetween being closed and opaque, a second pair of relatively larger egg-crate louvers overlying said first pair of louvers, each of said second louvers being inclined upwardly toward the center of the fixture from adjacent the outer margins of respective lower louvers, and at least two fluorescent bulbs mounted in the outer portions of the fixture to extend longitudinally over the lower louvers and beneath the upper louvers.

References Cited in the file of this patent UNITED STATES PATENTS 2,105,447 Arenberg Jan. 11, 1938 2,274,612 Johnston Feb. 24, 1942 2,337,685 Schepmoes Dec. 28, 1943 2,514,049 Graham July 4, 1950 2,523,581 Margolis Sept. 26, 1950 2,544,708 Margolis Mar. 13, 1951 OTHER REFERENCES Hospital Lighting Data Book, Catalog No. 41, of The Edwin F. Guth Co., St. Louis 3, M0. (1943) (page 17).

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