US2462243A - Luminaire - Google Patents

Description

Feb. 22, 1949. F. c. WINKLER ET AL LUMINAIRE 2 Sheets-Sheet 1 Filed July 18. 1944 INVEN TORS Bur/an 7. ln/ymqn and FFeaer/c C. Mh/r/er.

' ATTOR Y WITNESSES:

Patented Feb. 22, 1949 LUIVIINAIRE Frederic C. Winkler and Burton A. Wyman, Cleveland, Ohio, assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application July 18, 1944, Serial No. 545,422

4 Claims.

industrial application, utilizing low wattage light sources of the tubular type are usually made up of a hood assembly to the bottom of which is attached a trough-shaped reflector, the hood assembly usually comprising a trough-shaped hood member in which are mounted the lamp holders, electrical wiring, and other control accessories for the lamp or lamps. In this instance, the hood member functions as a wireway for the electrical wiring of the luminaire. In attempting to use high wattage lamps and, particularly, the 3000 watt mercury vapor lamp in luminaires of this general type, it Was found that the temperature developed by the lamp was such as to make it impossible to utilize conventional structures or designs for this purpose. It was found that the temperature in the wireway portions of the hood assemblies, regardless of the particular type used, greatly exceeded the temperature at which copper wire becomes oxidized and was far in excess of the temperature to which wire insulation may be subjected without damage thereto. In addition to the large amount of heat developed by the lamp, it was found necessary to take into consideration the high ambient temperature conditions under which luminaires of this type are usually used. Such luminaires are frequently used in steel mills and places of similar nature where very high ambient temperature conditions exist, which further complicated the problem of providing a luminaire for use with such high wattage lamps that would be satisfactory under all operating conditions.

In one attempted design, the temperature at the top of the reflector which was mounted within an inverted trough-shaped metal hood or housing Wasfound to exceed 140 C. In another attempted design, the temperature in the hood which formed the wireway exceeded 160 C. In both instances, the temperature at which the electrical wiring was subjected was far in excess of that which is permissible. This not only resulted from the excessive heat developed by the lamp but also from the fact that the wireway in the conventional design is very close to the lamp, and the reflector has a relatively small radiating surface.

Accordingly, it is an object of our invention, generally stated, to provide a luminaire for use with high wattage electric discharge lamps of the tubular type which shall be of simple and economical construction, and in which provision is made for maintaining the temperature in the wireway at such value as not to be injurious to the insulation of the electrical wiring of the luminaire under all operating conditions.

A more specific object of our invention is to provide a luminaire of the character described in which the wireway for housing the electrical wiring is thermally insulated from the other parts of the luminaire.

Another object of our invention is to provide a luminaire of the character described wherein the wireway for the electrical wiring is disposed in spaced or separated relation withrespect to the lamp.

A further object of our invention is to provide a luminaire of the character described wherein the hood assembly is formed of two end or terminal housings attached together by means of a pipe or tubular member'rigidly attached to the ends of the housings and separated an appreciable distance from the lamp or the top of the reflector.

A still further object of our invention is to provide, in a luminaire of this type, for readily making electrical connections to the lamp holders thereof either before or after installation of the luminaire without changing or interfering with the spacing of the lamp holders as originally installed.

Another object of our invention is to provide a lamp holder housing of the character described having a cover portion which may be readily lifted from its normal closed position to an open position to open the side or sides of the housing and provide access to an opening in the top of the housing through which a tool may be inserted to make wiring connections to a lamp holder terminal. 7

Another object of our invention is to provide a hood assembly of rigid mechanical construction for luminaires utilizing a high wattage electric discharge lamp which shall function to support the lamp and reflector and which also functions to protect the electrical wiring of the luminaire against damage due to the excessive heat developed by the lamp when in operation.

. Another object of our invention is to provide a hood assembly for luminaires of the character described utilizing a high wattage discharge lamp which shall be of rigid mechanical construction and which is so constructed as to allow its application to all the various types of suspension now in use.

These and other objects of our invention will become more apparent from the following detailed description when considered in connection with the drawings, in which:

Figure, l is a sidev elevational' view of a lumi naire embodying the principal features of our invention, this view being partially cut away to show the details of the end or terminal housing of the luminaire;

Fig. 2 is a partial top view of the luminaire of Fig. 1; and

Fig. 3 is an end elevational' view of the luminaire of Fig. l.

A preferred embodiment of our invention, as shown in Fig. 1, for example, comprises, generally. a hood assembly I0, a reflector I! supported,

thereby, and a light source in the form of a mercury vapor lamp I 2.

In the use of high wattage mercury vapor lamps, such, for example, as a 3000 watt lamp of the type illustrated, it becomes necessary to protect the electrical wiring of the luminaire against damage due to excessive heat developed by the lamp.

In order to provide this result, it has been found necessary to utilize a hood assembly of such nature that the wireway for carrying the electrical wiring of the luminaire is so efiectively insulated from the lamp or other portions of the luminaire which may become highly heated that the temperature on the inside of the wireway remains at such a value as not to damage the insulation of the wiring.

In this instance, the hood assembly I comprises a pair of end or terminal housings I3 and I I of generally rectangular shape rigidly connected together in end-to-end relation by means of a tubular member I5.

As shown best in Fig. 1, the tubular member I5 extends through suitable openings in the adjacent or facing ends of the housings and is attached to the end and top walls thereof in'any suitable manner, such as by means of welding at points I8 and II, for example.

Each housing; is formed; or two cooperating L- shaped members of flat material, one of which, indicated at, I8. forms the top and one end portion. and the other, indicated at I9, forms a bottom and the other end portion, the two members I8 and I9 being joined together at pointsv 2I- and 22: to form a rectangular enclosure which is open at. both. sides;-

The housing or enclosure thus formed is provided with knockouts 2.3 and 24- in the top thereof as well as an end: knockout 25 for the purpose of making electrical connections through the use of rigid conduit, or flexible conduit or for supporting the hood assemblyii desired.

Each end housing is also provided with a relatively large bottom opening 26 which receives the terminal portion 28 of the lamp holder 29 attached to the bottom of the housing as shown. It willbeunderstood that a lamp holder is provided at each end of the lamp and attached to each housing, as-shown in Fig. 1.

In this. embodiment of the invention, the tubular member, I5. which rigidly connects the end housings together addition to; its mechanical functioning, also is utilized as the wireway for carrying the electrical wiring of the, luminaire. The number of wires which extend through the tubular member I15 is determined by the manner in which the luminaire is connected to the current supply system.

In the embodiment shown, one electrical conductor 3I is shown extending through the wireway I5, this conductor being connected to the terminal of the lamp holder (not shown) mounted in the housing I4. The other conductor 32 is connected to the terminal 33 of the lamp holder 29.

In this instance, the wireway I5 is thermally insulated from the lamp I2 or the top of. the reflector II by spacing the tubular member I5 as far away therefrom as is necessary to reduce the temperature therein to a safe maximum, In this connection it will be noted that the tubular member I5 enters the ends of the terminal housings I3 and I4 at a point adjacent their top portions. This location of the wireway is such that the large amount of heat developed by the lamp I 2 cannot raise the temperature therein regardless of ambient temperature conditions to a point at which the insulation of the electrical wiring would become damaged.

In order to facilitate the making of electrical connections to the lamp holder 28, either before or after the luminaire has been installed, the top of each end housing is provided with an opening above the terminal portion of the lamp holder to permit the insertion of a suitable tool to make the electrical wiring connection.

As shown in Fig. l, the end housing I3 is provided with an opening 34 directly above the terminal portion 28 of the lamp holder. The object of the opening 34 is to permit the insertion of a tool for the purpose. of manipulating the terminal screw 33 on the. terminal portion of the lamp holder.

In order to provide for normally covering this opening 34 and still give access thereto when necessary, each of the end housings is provided with a U or trough-shaped cover portion 35.

This cover portion 35 has side portions 38 and 4 than the knockout 23, and likewise the opening 40 is of larger diameter than the knockout 24. The purpose of openings 39 and 40' in the cover member is to enable. the: cover member to be raised from. its normal position, as shown in Fig. 1, for example, so as, to uncover the opening 34. The openings 39 and III]: are of such size that the cover may be raised even though the luminaire is being supported bymeans of rigid conduits attached to the end housings at either one of the openings which may be provided by removing the knockouts 23 or 24. The cover 35 may be. attached to the end housing in any suitable manner, such as by means of the screws 41 engaging brackets 42 secured to the bottom portion I9 of the housing.

By means of this type of construction of the end or terminal housings I3 and I4,it is possible to accurately space the lamp holders, which is a necessary requirement, and permitthe electrical connections tobe made either before or after installation or the luminaire without in any way disturbing the spacing oi' the lamp holders. other words, the construction of theend housings is such that by raising the covers,. the terminal portions of the lamp holders are completely exposed, and-the terminal screws thereof maybe readily actuated by' a tool inserted through the top opening 34; i

In this embodiment of the invention, the reflector l l is detachably secured to the hood assembly ill by means of a plurality of wing locks. As shown, the housing l3'is provided with a wing lock 44 mounted in its bottom portion [9, and the reflector is provided at this end with a suitable opening 45 for receiving the lower end of the wing lock.

While .a separate reflector II has been shown for usewith a hood assembly of this particular type, it is to be understood that the reflector may be an integral part of the hood assembly if desired.

The luminaire of our invention may be sup-' ported in any one of several ways. It may be supported, for example, from rigid conduit through the use of openings in the end housings which may be provided by removal of anyone of the knockouts 23, 24,'and 25. It may also'be supported in a swinging manner by means of horizontally disposed bolts or rods extending through the openings 46 and 41 in the extensions 48 and 49, respectively, of the adjacent end portions of the housings l3 and I 4. When mounted in this manner, it is possible to swing theluminaire about its mounting bolts or rod, not shown, to an inverted position where any required servicing operation may be readily carried out.

While in this particular embodiment of the invention only a single tubular member I5 for rigidly connecting the end housings l3 and M has beenshown, it will be readily appreciated that a plurality of such tubular members may be utilized, if desired. It has been found, however, that a single tubular member welded to the end housings, as shown, provides sufficient strength andrigidity for the hood assembly, and at the same time provides the necessary space for carrying the electrical wiring between the opposite ends of the luminaire.

In view of the foregoing description, it will be apparent that our invention provides a luminaire for use with high wattage electric discharge lamps of the tubular type in which provision is made for adequately protecting the electrical wiring of the luminaire against damage due to the excessive heat developed by a lamp of this type. The structure disclosed accomplishes this result very effectively, but at the same time is simple and economical to manufacture.

The advantages of the structure employed as a result of our invention over the conventional structures will also be apparent from the foregoing description. While the hood assembly is not heavy or bulky, it, nevertheless, is strong and rigid due to the manner in which the end housings and tubular member extending therebetween are attached together.

An integral part of each end housing is utilized as a means of support for the hood assembly or luminaire regardless of the method of mounting or support used. Therefore, separate brackets or the like are not required, and the cover members need not be used for supporting the hood assembly. The mounting or supporting points of attachment of the luminaire are closely grouped over the center of the load, that is, the point of reflector attachment at each end of the hood assembly which places a minimum of distortional stress upon the wireway. The structural form of the end housings used together with their removable cover member makes it readily possible to utilize an opening in the top of each end housing to facilitate the making of electrical connections to the lamp holders. This feature is obtainable without sacrificing strength of the end housings. The fact that removable covers are used for the end housing also facilitates wiring of the lamp holders and makes conduit attachment easy.

While we have disclosed one particular embodiment of our invention, it will be apparent that other embodiments of our invention may be made without departing from the principles thereof.

We claim as our invention:

1. A luminaire for use with highwattage electric discharge lamps of the tubular type 'which develop a large amount of heat comprising, a hood assembly including a pair of spaced apart end housings and a tubular member rigidly interconnecting said housings and terminating there in, said housings being open at the sides and having top and bottom openings, a, lamp holder attached to each housing with their terminal portions extending within the housings through said bottom openings, and a U-shaped cover for each housing normally positioned to close the side and top openings and disposed to be lifted to open the housing and uncover the topopening, thereby to permit the insertion of a tool to make'w ire connections to the lamp holders without disturbing the spacing adjustment of the lamp holders.

2. A hood assembly for a luminaire comprising a pair of end housings, a tubular member rigidly connecting said housings together in spaced endto-end relation, said housings being formed of two L-shaped strap members secured together in rectangular form to form a frame with open sides and having at least one knockout and an opening in the top portion thereof and an opening in the bottom portion thereof, a lamp holder secured to the bottom portion of each housing having a terminal portion extending into the housing through the bottom opening opposite said opening in the top portion, and a U-shaped cover for each of said housings having a top portion normally covering said opening and an opening therein of larger diameter than the knockout and coincident therewith, whereby said cover may be moved upwardly to permit the insertion of a tool through said top opening to facilitate making wiring connection to the lamp holder, when a wiring conduit is attached to the housing at the opening provided by removal of said knockout.

3. A luminaire for use with high wattage electric discharge lamps of the tubular type comprising, a pair of spaced housings having open sides and top and bottom openings, a U-shaped cover for each housing detachably secured thereto and normallycovering said side and top openings, said cover being movable to expose and give access to said openings, a lamp holder attached to the bottom of each housing with its terminal portion extending through the bottom opening into the housing and its lamp supporting portion extending therebelow for supporting the lamp beneath the housings, a continuous tubular member rigidly interconnecting said housings and terminating therein adjacent their top portions, said tubular member, being exposed to the atmosphere throughout its length between the housings and functioning both as a rigid connection for the housings and as an exposed wireway for the electrical wiring, an inverted troughshaped reflector, and means carried by the housings for detachably securing the reflector thereto, said reflector having spaced openings therein 7 through: which the; lamp; supporting; portions of thalamnholders extend and having its top surface spaced from the exposed: tubular wire- Way between: thehousings, therebytoprovide for thermally insulating the: wireway from the reflector andlamp. V

4. A; hood: assembly for a luminaire utilizing an elongated tubular lamp comprising, a. pair'of endhousings, atubular member rigidly connecting said housings together in end-to-end relation and communicating with the interior thereof, saidhousings each being formed of two L-shaped strap members joined together to form a. rectangular frame with open sides, one ofsaid. strap members of each pair having an extended leg portion positioned above the top of the housing for supporting the assembly, each of said housings having a bottom opening and a top opening thereabove; a lamp holder mounted on each housing over said bottom opening with its terminal portion within the housing and its lamp supporting portion therebelow for supporting the lamp below and in spaced relation with the housings and tubular member, a cover member for each housing, said cover members having spaced side portions normally closing the side openings of the housings and a connecting portion extending over the top openings of the housings, whereby the covers may be moved to expose the side and top openings to permit tools tobe inserted into the 8 housing through; said 0: to; mam wiring connections and. the; like. while. the: lamp; holders are attached in their normal position;v

FREDERIC C. WINKIER. BURTON A.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 602,966 Wallach Apr. 26, 1898 1,990,109 Hendry Mar; 7', 1933 2,153,366 Darley- Apr. 4, 1989 2,270,814 Scribner Jan. 20, 1942 $295,788: Hoeveler: Sept; 15,1942 308,986 Livers Jan. 19; 1943 2,313,983 Yost. et a1. Mar. 16, 1943 2,318,535 Stern May. 4, 1943 2-,376;80l. Mitchell May 22; 1945 $392,202: Tornblom Jan. 1, 1946 OTHER. REFERENCES Catalog, #400 'by Mitchell-Mfg. Co.,, Chicago, Ill. (eight pages) (in' U. 8. Patent Oflice, Apr. 22, 1943).

Bulletin E69 by Day Brita- Lighting, St. Louis,

Mo. (four pages)- (in U. S. Patent Oflioe, Aug. 14,-v

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