Claims:
I claim
1. In a decorative light string, including a plurality of sockets interconnected by a power cord serving to maintain said sockets in spaced relation, and supply power thereto, the improvement comprising: each of said sockets having first and second socket body elements, each having a power-cord-clamping portion, a sleeve element constructed and arranged to hold said body elements in juxtaposed position with said cord held in said power-cord-clamping portion; each of said first and second socket body elements having a principal longitudinal axis and an inner surface thereof, there being a plurality of longitudinally arranged grooves therein communicating with said surface, and elongated contact members slideably disposed in each of said grooves and frictionally retained therein, each of said contact members having a wire-engaging point on one end thereof adjacent said power-cord-clamping portion, said grooves exposing elongated side segments of said contact members; said power cord including first and second electrical conductors, insulation surrounding said conductors and maintaining them in parallel mutually insulated relation; said cord being severed at periodic intervals with respect to one of said conductors to form a hiatus, said first and second socket-forming elements enclosing said power cord in the area of said hiatus, whereby said contact members complete a circuit through said socket, the other of said conductors passing in insulated relation through said socket, whereby a plurality of sockets may be interconnected for series current supply to a source of power.
2. Structure in accordance with claim 1, in which said socket includes a wedge-shaped member adapted to be projected into said hiatus upon engagement of said socket forming elements upon said power cord to enlarge said hiatus, whereby the hiatus may be formed solely by a single cut of one of the conductors.
Description:
This invention relates generally to strings of electric lights and more particularly to a new and useful decorative midget light string construction and method of making same.
It is known in this art to have a string of lights in the form of small incandescent bulbs which are connected to sockets by pushing the bulb into a receptacle in the socket. The connections to the socket are made by hand by soldering or crimping cut wire ends of twisted electrical cord to contact members and hand assembling the same into the socket. This construction and method is time consuming and costly.
It is among the objects of the present invention to improve upon the prior art constructions and methods and to provide structure and methods of the class described which are lower in cost of manufacture and assembly, more durable, neater and trimmer in appearance, and which provide for enhanced decorative appearance.
These objects and other incidental ends and advantages will more fully appear in the progress of this invention and be pointed out in the appended claims.
In the drawing, in which similar reference characters designate corresponding parts throughout the several views:
FIG. 1 is an exploded, fragmentary perspective view showing an embodiment of the invention.
FIG. 2 is an enlarged elevational view of a second socket body element as seen from the plane 2--2 in FIG. 1.
FIG. 3 is an enlarged sectional view, partly in elevation, as seen from the plane 3--3 in FIG. 1, with a bulb inserted.
FIG. 4 is a sectional view as seen from the plane 4--4 in FIG. 3.
FIG. 5 is an enlarged elevational view of a contact member.
FIG. 6 is an elevational view as seen from the right of FIG. 5.
FIG. 7 is an exploded, fragmentary perspective view of a modification.
FIG. 8 is an enlarged elevational view of a first socket body element as seen from the plane 8--8 in FIG. 7.
FIG. 9 is an enlarged sectional view as seen from the plane 9--9 in FIG. 7.
FIG. 10 is an enlarged sectional view corresponding to that seen in FIG. 9, but showing another modification.
Turning to FIGS. 1 to 6, in accordance with the invention, the construction, generally indicated by reference character 10, comprises broadly: sockets 12, an electrical power cord assembly 14, and electric incandescent light bulbs 16 (only one shown).
An electric light bulb socket 12 includes first and second body elements 18 and 20, first and second contact members 22 and 24, and a sleeve element 26.
The body elements 18 and 20 are substantially identical so that they are completely interchangeable with each other, thereby reducing mold and inventory costs. Each is preferably molded of a fire-resistant synthetic resin of a suitable type, such as thermosetting phenol resin, polyvinyl chloride resin, polypropylene, or the like. The elements 18 and 20 are generally half cup shape including bases 28 and 30; and upstanding semicylindrical walls 32 and 34 with upper edges 33 and 35. The vertical edges 40 and 42 of the walls 32 and 34 have pairs of power-cord-clamping portions 36 and 38, vertical grooves 44 and 46, and vertical setback portions 48 and 50, respectively. The lower portions of body elements 18 and 20, at the outside thereof are of greater diameter, forming shoulders 52 and 54, and thereabove the body elements have horizontal grooves 56 and 58.
The sleeve elements 26 are generally cylindrical in shape, with an internal diameter which is a sliding fit on the upper portions of the exterior surfaces of the walls 32 and 34 when the vertical edges 40 and 42 are in contact. Disposed on the inner surface of each of the sleeve elements is a annular horizontal rib 60 which is by its arrangement and construction adapted to snap into engagement with the grooves 56 and 58.
Thus the sleeve elements 26 retain the body elements 18 and 20 in assembled juxtaposition. The lower edges 62 of the sleeve elements 26 abut the shoulders 52 and 54. The sleeve elements may be in a variety of colors and may have many different decorative edge treatments such as the serations 64. As desired, the sleeve elements 26 may have integral hooks 66 which may serve to support sockets 12 in selected positions, as for example on the twigs of a Christmas tree.
The first and second contact members 22 and 24 have top ends 68 and 70, lower ends 72 and 74, vertical edges 76, 77, 78, and 79, outer surfaces 82 and 84, and inner surfaces 86 and 88. The lower ends 72 and 74 at the rear portions thereof (as viewed in FIG. 1) are provided with wire-engaging points 90 and 92. In assembled condition, the members 22 and 24 are disposed in the opposed grooves 44 and 46 which retain said members against lateral displacement. The points 90 and 92 pass through the insulation 91 to make electrical connection with the wire 94 while the flat portion of the ends 72 and 74 may contact the insulation 93 on the wire 96. The contact members 22 and 24 are retained against vertical upward displacement by the protuberances 95 and 97 which press against or into the inner surfaces of the walls 32 and 34.
The bulbs 16 are of the miniature type having a base 98 and a top flange 99, aligning lugs 100, wire terminals 101, and support block 102. The wires leading from the filament in the bulb are brought down through holes in the block 102 and folded outward and upward. When a bulb 16 is pushed down into a socket 12, the lugs 100 are positioned between the opposed setback portions 48 and 50, and the terminals 101 are pressed against the inner surfaces 86 and 88 of the contact members 22 and 24.
The electrical power cord assembly includes the well-known attachment plug 13 and the circuit-closing double jack 15 so that depending upon the supply voltage, and the resistance of each bulb 16, a plurality of sockets 12 are hooked-up in series with the return by the wire 96 which is continuous from jack 15 to plug 13.
Constructed by my inventive method is simple, quick, effective and economical. Depending upon the number of bulbs and sockets desired in the finishing string, the wire 94 and its insulative jacket 91 is cut out at predetermined locations 11 therealong. These become keying notches for further assembly. At each such keying notch, a first body element 18 is placed with the ends 11a and 11b in the power-cord-clamping portions 36. Next the second body element 20 is placed against the first body element 18 with the wire 96 and jacket 93 in the portions 38. This clamps the cord and when the sleeve element 26 is pushed down in place, a socket 12 is formed and is securely clamped in place. The bare ends of the wire 94 are protected within the socket 12. Next the bladelike contact members 22 and 24 are pushed into the grooves 44 and 46 until they are in the position shown in FIG. 3. The process is continued for each socket until the string is complete. Placement of the bulbs 16 makes the assembly ready for use.
Turning to the modification shown in FIGS. 7,8 and 9, to avoid needless repetition certain of the parts are given the same reference characters as the prior-described embodiment with the addition of a prefix "2."
In the modification, one of the body elements, first body element 218 is provided with an insulating separator 217 which is preferably cast integrally with the lower inner surface of wall 232 and the upper surface of base 228. The separator 217 is preferably of wedge shape having a top surface 219, and converging surfaces 221 and 223 which meet at sharp edge 225.
Construction by my modification method avoids the cutting out of portions of the wire 294, but merely cuts the jacket 291 and the wire 294 at predetermined locations 211 therealong. These become keying cuts for the further assembly. At each such keying cut, a first body element 218 is pressed toward said cut with the edge 225 entering between ends 211a and 211b. The surfaces 221 and 223 force the ends 211a and 211b apart and the separator 217 becomes an insulating barrier between the bare ends of wire 294. The ends 211a and 211b become positioned in the power-cord-clamping portions 236. Next the second body element 220 is placed against the first body element 218 with the wire 296 and jacket 293 in the portions 238. This clamps the cord 214 and when the sleeve element 26 is pushed down in place over the elements 218 and 220 a socket 12 is formed and is securely clamped in place. Next the bladelike contact members 22 and 24 are installed in the manner previously described in connection with the main embodiment.
Turning now to the modification shown in FIG. 10, to avoid needless repetition, parts corresponding to those of the modification shown in FIGS. 7 to 9, inclusive, have been given reference characters as in the principal embodiment, with the additional prefix "3."
In this modification, the insulating separator 317 is of bladelike configuration, as contrasted with the wedge shape of the embodiment shown in FIGS. 7 to 9, so as to be more readily insertable in the keying cuts.
I wish it to be understood that I do not consider the invention limited to the precise details of structure shown and set forth in this specification for obvious modifications will occur to those skilled in the art to which the invention pertains.