Abstract:
A globe hub for a casual electric light fixture comprising a cap and a globe holder connectable at a point of joinder by fasteners. Electrical wires extend into the interior of the hub through access openings located at the point of joinder, being connected to a lamp socket held by the globe holder. Wire gripping surfaces extend from the interior of the cap and the globe holder, engaging and anchoring the wiring securely within the hub and allowing stresses imposed thereon to be evenly distributed, thereby avoiding damage to the electrical connection.

Description:
TECHNICAL FIELD 
     This invention relates to globe hubs for electric light fixtures. More particularly, this invention relates to multiple, spaced-apart light fixtures connected to each other by lengths of electrical wiring. Specifically, this invention relates to electric light fixtures interconnected by extendable spiral coils of electrical wiring, especially to those that are suspendable in festoons, and to methods for securely fixing wiring thereto. 
     BACKGROUND OF THE INVENTION 
     Casual lighting, that is lighting provided for usually temporary purposes, or lighting provided as an afterthought in particular locations, is commonly required or desirable in a variety of applications. Such lighting, for example, is oftentimes used at cookouts, for pool or patio parties, as well as at campsites, and is sometimes attached to the outside of stationary recreational vehicles. Beyond such temporary uses, however, casual lighting is also often resorted to for illumination in more permanent settings, for instance, in basements, game rooms, at job sites, and the like. 
     Such lighting is of considerable convenience in such situations since it is portable and can be rapidly installed without any need for more permanent fixtures or wiring. It is also easily removed when no longer required. Casual lighting lends itself to installation in areas and in positions in which the provision of more permanent lighting would be impractical, undesirably expensive, or unfeasible. 
     While casual lighting is a considerable convenience in many situations, it is not without attendant problems resulting from its temporary nature. For example, it is typically free-standing, that is, it is not &#34;hard-wired&#34; to fixtures anchored to ceilings or walls, or equivalent permanent structures, but rather is loosely attached or temporarily suspended from supports and it normally involves exposed wiring. While such disposition facilitates deployment of the lights, it also makes them more vulnerable to accidents in which severe strains can be imposed on the points at which the wiring is connected to the lights. In addition, in instances where the lights are suspended only by their own wiring, the weight of the lights themselves results in such strains. When subjected to stresses and strains of the type described, wiring used in the lights&#39; electrical connections can become disconnected or otherwise damaged, sometimes resulting in an inconvenient failure of the lights, or in more serious cases, to exposure of individuals coming in contact therewith to electrical shock. 
     These possibilities have led to design modifications in such lights for the purpose of the type described typically comprise structures, or &#34;hubs&#34;, into which electrical lamps are screwed, and which are connected to wiring extending into one or both sides thereof. Commonly, globes are positioned about the lamps, being held by the hubs, both to better diffuse the light emitted therefrom, as well as to provide a more decorative appearance to the fixtures. In the past, the strengthening referred to has involved the fashioning of the top of the hubs in the shape of a rigid &#34;T&#34;, the electrical wiring being inserted in the horizontal arms thereof, which hold and protect it. The expedient described is not altogether effective in providing protection to the connections, however, and it unfortunately detracts from the aesthetic qualities of the lights. In this regard, lights of the type described are not simply functional, but in many instances, are intended to be decorative as well. However, when hubs shaped as described are used, they tend to impart an unattractive geometric, rather stiff appearance to the lights, as well as to interfere with their disposition in graceful festoons. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In view of the preceding, therefore, it is a first aspect of this invention to provide a globe hub for a casual light fixture that is attractive, as well as functional. 
     It is a second aspect of this invention to provide a globe hub for a casual light fixture that protects the electrical wiring connected thereto from becoming accidentally disconnected. 
     An additional aspect of this invention is to provide a globe hub for casual light fixtures that allows the fixtures to be hung in graceful festoons. 
     Another aspect of this invention is to provide a globe hub for a casual light fixture that facilitates the secure attachment of electrical wiring thereto. 
     A further aspect of this invention is to provide a globe hub for a casual light fixture that allows electrical wiring to be attached to the hub both rapidly and easily. 
     Yet another aspect of this invention is to provide a globe hub for a casual light fixture that prevents the inadvertent detachment of electrical wiring therefrom. 
     Still an additional aspect of this invention is to provide a globe hub for a casual light fixture whose connection to the wiring supplying electricity thereto is sufficiently sturdy to withstand significant amounts of stress placed thereupon. 
     The foregoing and other aspects of the invention are provided by a globe hub for a casual electric light fixture comprising a cap connectable to the top of a globe holder as a cover therefor. The cap and the globe holder are provided with openings therein adapted to receive electrical wiring therethrough for connection to an electric lamp held in the hub. The cap and the holder are also provided with a plurality of gripping surfaces extending from interior surfaces thereof, adapted to hold and immobilize electrical wiring in contact therewith. 
     The foregoing and additional aspects of the invention are provided by a globe hub for a casual electric light fixture comprising a circular cap in the form of a hollow cylinder substantially closed on its upper end and having a rim whose open lower end is provided with a grooved annular surface having at least one semicircular opening therein. The cap has two spaced-apart lugs extending downwardly from the lower surface of its closed upper end, the lugs having outwardly facing shoulders thereon. 
     The hub also includes a globe holder having an upper hollow cylindrical portion with an additional grooved annular surface provided with at least one semicircular opening therein. The upper cylindrical portion is substantially closed on its lower end, while the substantially closed lower end has an opening therein. Means are provided for attaching the cap to the globe holder, and when so attached, the annular surface of the cap and globe holder are adapted to engage each other in a mating relationship so that the semicircular openings are aligned and the lugs extend through the opening. When so disposed, electrical wiring extending through the semicircular openings and through the hole in contact with the shoulders is immobilized. 
     The foregoing and further aspects of the invention are provided by a globe hub for a casual electric light fixture comprising a circular cap including a hollow cylinder substantially closed on its upper end, the rim of the lower end being provided with a grooved annular surface having at least one semicircular opening therein furnished with a raised ridge. The cap has two spaced-apart lugs and also raised ridges extending downwardly from a lower surface of the closed upper end, the lugs having outwardly facing, stepped shoulders thereon. 
     The hub is also provided with a globe holder having an upper hollow cylindrical portion having a grooved annular surface with at least one semicircular opening therein provided with a raised ridge. The upper cylindrical portion is substantially closed on its lower end, the substantially closed lower end having an opening therein and raised ridges extending upwardly therefrom. The cap and the globe holder are attached to each other by threaded fasteners, and when so attached, their annular surfaces are adapted to engage each other, the lugs extending through the opening so that electrical wiring passing through the semicircular openings and through the hole in contact with the shoulders and the raised ridges is immobilized. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood when reference is had to the following drawings in which like-numbers refer to like-parts, and in which: 
     FIG. 1 is a cross-sectional view of the globe hub for a casual light fixture of the invention taken through the center of the hub along a centerline corresponding to the axis of the openings through which the wires enter the fixture. 
     FIG. 2 is a bottom view of the cover cap of the globe hub of FIG. 1. 
     FIG. 3 is a top view of the globe holder of the globe hub of FIG. 1. 
     FIG. 4 is a pictorial view of a festoon of casual lights utilizing globe hub fixtures of the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 is a cross-sectional view of the globe hub of the invention taken through the center of the hub. As illustrated, the hub, generally 10, consists of a cover cap, generally 12, and a globe holder, generally 14. The cap 12 comprises a hollow cylinder, closed on the top and open on the bottom, having semicircular openings 17 aligned along the horizontal axis of the cap, on either side thereof. The openings 17 are provided with a raised ridge 16 which serves to grip electric wiring 32, shown in phantom, extending therethrough. 
     The cap 12 is also provided with spaced-apart lugs 34 extending downwardly from the top of the cap, and having outwardly facing shoulders 24 and 24a, which also serve to grip the wiring 32. Further, the top of the cap 12 has a raised ridge 20 projecting downwardly from the lower surface of the cap, providing a still further gripping action on the wiring 32. A hanger hook 26 extends from the top of the cap 12, allowing the globe hub 10 to be suspended from a suitable support. 
     Fastened to the cap 12 by threaded fasteners whose location is better seen in FIGS. 2 and 3 is a globe holder 14. The globe holder includes an upper hollow cylindrical portion, also provided with semicircular openings 17a having a raised ridge 16a extending therefrom for the purpose of gripping the wiring, and raised ridges 22 and 22a which supplement the gripping action. 
     In the process of attaching the wires, the cap 12 is disassembled from the globe holder 14 by removal of the fasteners referred to, and electrical wiring is introduced through semicircular openings 17a, over raised ridges 22 and 22a. The wiring is then forced downwardly through an opening 42 in the substantially closed lower end of the upper hollow cylindrical portion 18 of globe holder 14, and is electrically connected to the bulb holder 28. The cap 12 is then placed in position over the electrical wiring and connected to the globe holder 14 by means of the aforesaid fasteners. When so positioned, the raised ridges 16, 16a, 20, 22 and 22a, and the lug shoulders 24 and 24a grippingly engage the wiring. The cumulative effect of the shoulders, the raised ridges, and the threading of the wiring through opening 42 is to so securely fasten the wiring to the globe hub 10 that the connected structure is able to support a significant deadweight, i.e., depending upon the type of wiring and the dimensions of the globe hub components, up to about 35 pounds. 
     Following assembly as described, an electric lamp can be inserted in the lamp holder 28 and a globe mounted in the lower cylindrical portion 37 of the globe holder 14, for example, by means of threads 30. 
     FIG. 2 is a bottom view of the cover cap of the globe hub of FIG. 1. The Figure shows the axially aligned semicircular wiring openings 17, including the raised ridges 16 provided therein, located in the annular sealing rim 38 of the cap. The rim 38 is provided with annular grooves 39 and 39a for the purpose of matingly engaging counterpart grooves in the rim 41 of globe holder 14. Lugs 34, with shoulders 24 and 24a, and raised ridge 20 can be seen extending downwardly from the lower surface of the cap. Fastener holes 36 are provided to accommodate the connecting fasteners 36a, as previously described, and the grooves 39 and 39a serve the purpose of providing a weatherproof seal between the cap 12 and the globe holder 14. While one ridge 20 is shown, additional ridges can be provided, if desired. In like manner, while two lug shoulders 24 and 24a are illustrated, additional shoulders can be furnished where added support is required. 
     The dimensions of the cap 12 are not critical; however, its diameter will typically be from about 11/2 inch to 11/4 inch, while the lugs will be about 1/2 inch high and 3/8 inch wide. 
     FIG. 3 is a top view of the globe holder of the globe hub of FIG. 1. Shown in the Figure is the upper cylindrical portion of the globe holder 18, and its rim 41. The rim 41 contains grooves 40 and 40a provided for weather-sealing purposes, as previously indicated. The rim also includes semicircular openings 17a provided with a raised ridge 16a for gripping wiring extending through the openings. Raised ridges 22 and 22a extend upwardly from the substantially closed lower end of the upper cylindrical portion, and an opening 42 is provided for entry of the lugs 34, as well as the wiring 32. 
     The lower cylindrical portion 37 of the globe holder 14 is also shown, including the globe holder threads 30. Fastener holes 36 allow attachment of the globe holder to the cap, as previously described. 
     As in the case of the rim 28 of cap 12, the number of grooves in the rim 41 can be altered and greater or fewer raised ridges 22 and 22a may be furnished. 
     The dimensions of the upper cylindrical portion 18 will be compatible with the dimensions of the cap 12, and the access opening 42 will commonly be about 3/8 inch wide, and about 1/2 inch long. The semicircular holes 17a will have dimensions matching those of semicircular holes 17, and will depend upon the cross-sectional dimension of the wiring. Frequently, the semicircular holes will be about 3/16 inch in diameter, and the rims 38 and 41 will be about 1/8 inch wide. 
     FIG. 4 is a pictorial view of a festoon of casual lights utilizing globe hub fixtures of the invention. In the Figure, the festoon 44 shown consists of globe hubs 10 in which globes 48 are mounted suspended by hanger hooks 26 which engage hook eyes 46 attached to a ceiling 45. The globe hubs 32 are connected by extensible spiral coils of electrical wiring 32. The number of lights can be varied, depending upon the electrical characteristics of the circuit into which the festoon is connected and the wattage of the lamps being connected thereto. Usually, from about 6 to 8 lights of 60 watts each will be thus interconnected, although more or less than that number can be joined. 
     The globe hub can be formed from either metal or plastic; however, plastic is preferable particularly because of its dielectric characteristics. Plastics such as polyvinyl chloride, i.e., PVC; ABS; polystyrene, or others may be employed for the purpose. With respect to the globes, these will advantageously be made from a shatterproof plastic such as, for instance, polycarbonate, although other transparent or translucent materials can also be used. 
     Cord lengths can be varied to suit requirements of the application, four foot lengths of spiral coiled wire being common. The diameter of the globes can also be varied; however, globes of six to eight inches in diameter have been found to be well suited for the purpose. 
     Globe hubs of the type described in the preceding are especially valuable in fabricating strings of casual lights since the multiple points of gripping connection described allow strains imposed thereon to be distributed proportionately across the length of the connection, avoiding concentrated points of stress in the connection, and therefore, allowing greater stress loading than would otherwise be possible, without damage to the wiring. 
     While in accordance with the patent statutes, a preferred embodiment and best mode has been presented, the scope of the invention is not limited thereto, but rather is measured by the scope of the attached claims.