US3033982A - Luminaire guard - Google Patents

Description

May 8, 1962 R. T. BURNS 3,033,982

LUMINAIRE GUARD Filed Dec. 17, 1957 36 I N-H INVENTR Robert T. Burns ATTORNEY tates This invention rel-ates, generally, to protective equip ment for lighting fixtures, and more particularly to a wire protective device for a fighting fixture placed in an inaccessible area such as a high bay ceiling of a manufacturing plant to protect the lamp within the fixture from damage by missiles.

Before the present invention protective devices included a fabricated wire guard securely mounted over the main opening of the luminaire, with no provision for convenient removal of the wire guard to replace the lamp or expose the inner surfaces of the lighting fixture. Modifications of wire guards, presently in use, provide a large central hole in the face of the wire guard to permit passage of a lamp. Normally, the standard practice for replacement of lamps in high mounted lighting fixtures is to use a lamp changer, which is a spring clamp device on the end of a pole, permitting maintenance personnel to change lamps while standing on the floor under the fixture. When this practice is applied to fixtures equipped with wire guards, it is essential that the guards be so construted that lamps can be changed with little difiiculty. Accordingly, the wire guards currently marketed are provided with a large central hole of sufficient diameter in the face of the wire guard to permit passage of the lamp changer device with a lamp clamped in place. Consequently, because of the large hole in the wire guard, the area of the main opening of the lighting fixture exposed to missiles is reduced, but not substantially eliminated. Therefore, this type of wire guard sacrifices lamp protection to provide an access for ease of maintenance.

Accordingly, the primary object of this invention is to provide a novel protective device including a Wire guard affording maximum protection to a lamp within a lighting fixture, combined with maximum ease of lamp replacement.

Another object of this invention is to provide a novel wire guard for a lighting fixture that will permit the maximum amount of light to be transmitted therethrough with a minimum amount of light interference from the wire guard.

A further object of this invention is to provide a novel wire guard for a lighting fixture which will protect all areas of the opening of the lighting fixture.

Still another object of this invent-ion is to provide a novel protective device including a wire guard for a lighting fixture that can be readily removed to expose the inner opening of the fixture.

A more specific object of this invention is to provide a novel latching device for a wire guard for a lighting fixture which can be readily actuated from a distant point to expose the inner opening of the fixture.

Still another object of this invention is to provide an improved type of wire protective device which shall be suitable and economical of construction so as to provide maximum protection for a lighting fixture.

These and other objects of the invention will be more apparent upon consideration of the detailed description of preferred forms of the invention, when taken in connection with the attached drawings, in which:

FIGURE 1 is a top plan view illustrating the protective device embodying this invention;

FIG. 2 is a cross-sectional view of the lighting unit shown in FIG. 1, taken along the line II-TI of FIG. 1;

FIG. 3 is a partial cross-sectional view of the protective *2 atent O" 3,033,982 Patented May 8, 1962 device construction taken along the line tIII-'I'II of FIG. 1;

FIG. 4 is a partial cross-sectional view of the hinge construction of the protective device taken along the line IV;IV of FIG. 1 with the basket at an open position; an

FIG. 5 is an elevation view on a reduced scale of a lighting fixture to which the protective device is mounted.

The specific forms of this invention which are described and illustrated herein are protective guards for the normally open side of lighting fixtures through which light is emitted. For this purpose, it is preferable that the protective device be of a strong, light construction of minimum cross-sectional area to provide maximum protection from missiles and minimum interference to light emanating from the lighting fixture. It is also desirable that the protective device, when in service, be hinged so as to be movable to expose the lampholder and the inner surfaces of the lighting fixture.

In order to effect this protective result, as shown in FIG. 1, the wire protective device comprising this invention is comprised generally, of a split clamping support ring 10, a wire circular basket guard 12, pivotal about a hinge 14, and secured in the closed position by a spring wire latch 16.

The protective device is preferably made entirely of a relatively strong non-corrodable wire, such as heavily tinned steel wire. The split clamping support ring 10 is circular in shape and of approximately the same diameter as the lighting fixture housing 18 at its open end. The housing 18 is preferably made of metal, suchas a heavy guage sheet steel formed as an inverted cup-shaped en-, closure with a rolled beaded edge 20 about the periphery of the opening in cup-shaped enclosures. The split clamping support ring 10, is mounted to the housing 18 adjacent the beaded edge 20 by any suitable means. In the specific embodiment of the invention shown in the drawing, lugs 22, which may be formed of the same material as support ring 10, are spot welded to the clamping support ring 10 at spaced points 24.

As illustrated, the lugs 22 are formed of relatively short pieces of wire each of which is reversely bent back upon itself in the form of a U with the free ends of each lug secured to the support ring at the spaced points 24. The lugs 22 extend upwardly as viewed in FIG. 2 and are bent inwardly at an angle of substantially to en-. gage over the beaded edge 20 of the lighting fixture housing 18. At a point located between one pair'of adjacent lugs 22 the ends of the split clamping support ring 10 are located, and they are bent radially outward and formed into eyelets 26, of suitable diameter to receive a bolt 28. The bolt 28 extends through both eyelets 26 to threadedly engage a nut 30, preferably secured to the outer side of one eyelet 26 as by being welded or soldered to the eyelet 26. Adjustment of the circumference of split clamping support ring 10, can be made by increasing or decreasing the distance between the two eyelets 26, which is accomplished by turning the bolt 28 on nut 30. By adjusting the circumference of split clamping support ring 10, the inwardly extending portions 23 of lugs 22 move into or out of engagement with the beaded edge 20 of lighting fixture housing 18, thereby securely engaging or disengaging the split clamping support ring 16 to the housing 1 8. Also, by adjusting the circumference of the split clamping support ring 10, so that lugs 22 engage the housing 18, the split clamping support ring 10 engages the bottom side of rolled beaded edge 20.

A wire hinge member 14, extends radially outward of the support ring 10, and is secured as by being spotwelcled to the lower surface of the split clamping support ring 10. Hinge member 14 is U-shaped and preferably made of the same type of wire as support ring 10. The

3 bight portion of the hinge member 14 is secured to the support ring 16 and the outer end portions of the legs of theU-shaped hinge member 14 are bent to form eyelets 32. v V

f The wire basket structure or guard 12, has a circular wire basket support 34 of a material similar to the support ring 10, and is'of'a' greater diameter than the split clamping support ring 10, and is mounted on the hinge member 14, by passing the wire basket support 34, through the eyelets 32 of binge member 14. This assembly should be made prior to formation of the eyelets 32. A plurality of cross wires 38 emanating from 'a relatively small centrally located wire ring 36, extend point, the, cross wire members 38 are bent outwardly soas to extend radially outward of the wire ring 36.

The ends-of the cross wire members 38 may then be' bent' tightly around the wire basket support members 34 to be frictionally'held in place thereon. The number of cross wires 38, will be determined by the diameter of the split clamping support ring used andthe size of themissile that the lighting fixture is to be protected from To add n'gidityto the wire basketguard 12, a circular wire member 40 is secured as by being spotwelded to the cross wires 38, preferably at the point where each cross wire 38 is arcuately bent upwards.

As shown in FIG. 1, the two cross wires 42, which are located diametrically opposite thetwo cross wires 38 which are adjacent to the hinge member 14, have a latch support member 44 spotwelded or otherwise secured to an intermediate portion of thesecross wires at a location inwardly adjacent the circular wire memher 40. A generally U-shaped piece of wire is formed ,into a latch 16. The latch 16 has a shape as shown in FIG. 2, comprising a base portion 46 extending outward from the latch support member 44. Each base portion 46 of the latch 16 is comprised of the outer ends of legs of the latch 16 which are spotwelded or otherwise secured to the latch support member 44 and the circular wire member 40. The legs of the U-shaped latch 16, are bent upwardly at points 48located outward of the circular wire member 40 at an angle of substantially45" relative to the base portion 46. At points 50,

which are located a distancefrom the center of the wire.

guard 12 which is intermediate the radius of wire basket support 34 and support ring 10 and below the plane of the split clamping'support ring 10,v the legs of the U- shapedlatch are bent vertically upwards. ,At points 52 located adjacent to the upperside of the rolled beaded edge 20 of the lighting-fixture housing -18, and' above the planes of the split clamping support ring 10 and the wire guard support 34, the legs of the U-shaped spring wire latch 16 are inwardly bent to form a horizontal latch portion 54, substantially parallel. to the planes of split clamping support ring 10 and the wire basket sup- I port 34. The horizontal portions 54 of the latch 16 are extended a distance suflicieri t to engage and overlap the upper side of the rolled beaded edge 29. After extending this distance, the legs of the U-shaped spring wire latch 16 are substantially reversedly bent upwards 'at point 56, at an angle of approximately 45 and extended outwardly a distance sufficient to substantially exceed the outer diameterof wire guard support 34. The 'U-shaped spring wire latch 16, having its connecting portion outside of the wire guard support 34, thereby forms a; handle 58 which can I be operated to' release the U-shaped spring latch 16 upon application of a force downward. The horizontal portion 54, engaging the rolled beaded edge 29, securely holds the cross wires of the wire basket guard 12 in engagement with the split clamping support ring 10.

Upon releasing latch 16, the wire basket guard '12 will rotate about hinge member 14 exposing the inner.

portion of lighting fixture housing 18. FIG. 4 shows the wire basket guard in its open position.

The luminaire housing 18 may have a rolled beaded edge 20 as heretofore described, or any similarly shaped edge at the open end of housing .18, to which the split clamping ring 19 may be attached. As shown, a lampholder 6%) is mounted in housing 18, exposed to the opening of the cup-shaped lighting fixture.

The lighting fixture guardingdevice heretofore described can be operated to expose the interior of the lighting fixture housing by the use of lamp changing apparatus now in use. One of the standard practices for the replacement of lamps in high mounted lighting fixtures is to use a lamp changer which is a spring clamp device on the end of a pole and of suitable design to holda lam-p. Normally, the spring clamp device of the changer is so constructed that its lamp gripping fingers are hookshaped at their outer ends. This lamp changing device permits maintenance personnel to change lamps while standing on the floor under the fixture. The wire guard disclosed herein is a wire cover that can be opened orclosed wvith the use of a lamp changer to permit lamp replacement; To open the Wire basket or guard for lamp replacement merely requires the maintenance person to engage one of the hook-shaped fingers of the spring clamp device at the end of the pole with the latch on the wire guard. andthen exert a downward pull with the lampchanger which disengages the latch from the beaded edge of the fixture. The wire guard then rotates about the hinge thereby exposing the inner portion of the lamp fixture housing. Closing the wire guard after lamp replacement is accomplished by applying the lampchanger to the outer surface of the Wire guard and with an upward thrust of the pole swinging the wire guard into position over the fixture opening and cause the latch to snap into engagement with the beaded edge of the lighting fixture.

In view of the foregoing detailed description of a preferred embodiment of my invention, it will be apparent that I have provided a low cost wire guarding device to protect lighting fixtures.

My invention further provides a wire guarding device which can be readily, temporarily or permanently mounted, but the guard portion of which is relcasably latched at its operative position and can readily be rotated away from its protective position to exposethe inner surfaces of a lighting fixture for maintenance purposes.

While the preferred embodiments of my invention have been disclosed and described in detail herein, it is to be understood that the principles of my invention may be readily embodied in equivalent structures.

I claim as my invention:

1. A lighting fixture protective device for a dish shaped lighting fixture housing having an opening, said device comprising a split clamping support mounted on the periphery of said opening, a hinge mounted on said clamping support, said hinge pivotally mounting a guard, the outer periphery of said guard being substantially concentric to and of similar shape as said clamping su port, a U-shaped latch mounted on said guard substantially diametric to saidhinge mounting, said U-shaped latch mounted on the lowermost portion of the protective guard and arcuately bent outwardly and upwardly to a point above said clamping support, said U-shaped latch being then bent inwardly to engage the outer periphery of said housing and then arc'uately bent upwardly and outwardly to form'a handle, cross members emanating from the center to the periphery of said guard forming a protective basket for said opening. v f I 2. The combination comprising an inverted dished dished shape with an upper wire member forming the rim of the guard and attached to and pivotal about said-hinge, cross wire members forming the bottom of the guard emanating from the center of said guard and being arcuately bent upward at their outer portions to engage the bottom surface or" the clamping support and attached to the upper wire member at their outer extremities to thereby cooperate with said clamping support to absorb shocks from missiles that would otherwise strike the housing.

3. A lighting fixture protective device fora dish shaped lighting fixture housing having a bottom opening, said device comprising at least two substantially concentric Wire rings, means on the innermost ring for attaching said ring to the periphery of the opening of said housing, a U-shaped wire hinge mounted on the bottom surface of said inner wire ring with the legs of the hinge extending outwardly, said legs of the hinge being upwardly curled at their outer portions to form eyelets to pivotally mount the outer concentric wire ring which passes through the eyelets, said outer concentric wire ring having cross members emanating from the center of said outer concentric wire ring and in a plane below the plane of the outer concentric wire ring, with the outer portions of said cross members being bent upwards at a radius less than the radius of the inner wire ring, said cross members then being reversedly bent to engage the bottom portion of the inner ring, said cross members being secured to the outer ring, a latch located substantially diametrically to said hinge and securely attached to the lowermost portion of said cross members, said latch being substantially C-shaped in elevation with its outer portion reversedly bent outwardly and upwardly to form a handle, said latch releasaoly engaging said outerring to form a wire that may be opened or closed.

4. The combination comprising a dished lighting fixture housing having an opening, a lamp holder secured within said housing and being accessible through said guard opening, a split clamping-support mounted on and engaged with the periphery of said housing opening, a hinge mountedon said clamping support, said hinge pivotally .mounting a guard ring, said guard ring being substantially concentric to and coextensive said clamping support, said guard ring having cross members secured thereto, a

'U-shaped latch mounted on said guard ring substantially opposite to said hinge mounting, said U-shap'ed latch secured by its legs to said guard ring and arcuately bent upwardly to be substantially C-shaped in elevation and then reversedly bent upwardly and outwardly to form a I handle, the top of the 6 part of said latch Where it is *1" reverse'dly bent releasably engaging the periphery of said housing opening, said latch being operable to release said guard ring whenthe handle is depressed thereby allowing said guard ring to be pivoted about the hinge axis to expose the inner surfaces of said lighting fixture.

References Cited in the file of this patent Canada Feb. 6, 1951

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