US 3233207 A
Description (OCR text may contain errors)
Feb. 1, 1966 J. M. AHRONI ETAL DECORATIVE LIGHT Filed Feb. 21, 1964 JOSEPH M. AHRONI LEE AHRONI INVENTORS.
ATTORNEYS United States Patent 3,233,207 DECORATIVE LIGHT Joseph M. Ahroni and Lee Ahroni, both of R0. Box 3907, Seattle, Wash. Filed Feb. 21, 1964, Ser. No. 346,463 4 Claims. (Cl. 339145) The present invention relates to incandescent lights for decorating Christmas trees and other festive objects, and more particularly to an improved plug-in type lamp and socket assembly therefor.
Important objects of the invention are to provide such an assembly which is of simple and economical construction, and in which the lamp can be easily inserted into and removed from the socket when desired, but in which the lamp will not disengage from electrical connection with its socket while in storage or use due to jarring or vibration as has been the ditliculty commonly experienced with Christmas tree lights in the past.
Other more particular objects and advantages of the invention will, with the foregoing, appear and be understood in the course of the following description and claims, the invention consisting in the novel construction and in the adaptation and combination of parts hereinafter described and claimed.
In the accompanying drawings:
FIG. 1 is a perspective View of an assembled lamp and socket unit embodying the present invention;
FIG. 2 is an exploded view in vertical section of the lamp and socket components;
FIG. 3 is an enlarged horizontal sectional view taken as indicated by the line 33 in FIG. 1; and
FIG. 4 is a detail perspective view of the contact and related power lead which occupies the cavity of the socket unit.
Referring to the drawings it is seen that the incandescent electric lamp and socket of the present invention are designated and 11, respectively, and that the insulated power leads to the latter numbered 1212. A Christmas tree lighting set comprises a string of these sockets wired in series with a conventional plug for a wall socket. The set may be provided with a movable sleeve 13 adjacent each socket 11 whereby the socket can be positioned on a tree branch by inserting the branch between the leads 12 and between the sleeve and the socket, and then sliding the sleeve toward the socket to clamp the branch therebetween.
The lamp 10 comprises a plug unit 14 and an incandescent bulb 15 of the wire-base type wherein the spaced filament lead 16a-16b project from the base of the bulb. Both the plug 14 and the socket 11 are molded from polypropylene or some other suitable electrically non-conductive material. The main body 17 of the plug is generally cylindrical and has an annular stop flange 18 at the top rimming the mouth of a cavity in which the base of the bulb 15 is seated. A suitable adhesive 19 may be used to secure the bulb in the cavity 20 or the frictional grip of the filament leads 16a-16b in the socket 11, as will hereinafter be described, may be relied upon for this purpose.
The generally cylindrically shape of the plug 14 is modified by a concave side face 17a in the main body 17 and by a prong prolongation 21 located diametrically opposite the center of the plug from such face. It will be noted that the plug has two longitudinal through bores 22-23 each opening at the top to the cavity, the first extending to the base of the plug proper while the other continues through to the tip of the prong 21. Threaded through these bores and doubled back outside the plug are respective of the leads 16a-16b, the lead 1611 over the concave face 17a and the lead 16b over the outer face of the prong.
Continuing to the socket 11, it is seen that such has an enlarged head section 24 at the top of a cylindrical base section 25. The head section 24 is internally formed with the principal socket cavity 26 to receive the main body 17 of the plug while the base section 25 has a pair of longitudinal through-bores 27a-27b extending from the floor of the cavity 26 to the bottom end of the socket. Socket bore 27b is positioned to register with the :prong 21, but is slightly larger in diameter to receive a brass ferrule contact 28 which is spaced from the lower end of the socket. The other socket bore 27a terminates adjacent a convex wall 26a in the cavity 26 which matches generally the concave plug face 17a. However, this convex wall 26a terminates at endwise slots 29-29 and is sufiiciently spaced from the plug face 17a when the plug is seated in the socket to provide a gap for housing an arched brass contact 30 and to accommodate the filament lead 16a. This contact fits by its side edges in the slots 29 and has a bottom tab 30a which is doubled back between the contact proper and the convex wall 26a. The end portions of the power leads 12 are threaded with their insulation through the base of the socket bores 27a-27b and have their terminal end portions bared of insulation. The bared end of the lead in bore 27a extends into the socket cavity 26 and is looped around the contact tab 30a (FIG. 4) for connection thereto while the bared end of the lead in bore 27b is secured within the ferrule contact 28 as by solder 31.
Assembly of the socket 10 may be performed by threading the leads 12 completely through the bores 27a27b and cavity 26, and then, after stripping the insulation from a short terminal portion of the leads either before or after the threading step, applying the contacts 28 and 30. In the case of the ferrule contact 28 this is accomplished by crimping or by dropping a head of solder onto the bared end of the lead and then sleeving the ferrule thereo-ver until it engages the insulation. Similarly, after the lead for the contact 30 is wound over the tab 30 a drop of solder may also be applied thereto although a firm crimping of the tab against the contact proper will normally assure sufiicient connection. In any regard the leads 12 are then pulled back through the socket until the ferrule 28 is completely seated by a snug lit in the bore 27b and the contact 30 is seated against the floor of the cavity 26 and with its side edge portions in the slot 29.
The prong 21 is slightly smaller in external tolerance than the internal diameter of the ferrule 28 to accommodate the thickness of the filament lead 16b, and as before mentioned, similar space provision is made for lead 16a between contact 30 and the plug face 17a. Thus when the lamp 10 is plugged into the socket 11 with the prong 21 projecting into the ferrule 28 and the stop flange 18 seated against the upper end of the socket, the doubled back portions of the leads are pressed, one against the inside wall of the contact 30 and the other against the inner concave wall of the contact 28. The lamp can be easily manually pulled from the socket for replacement or color rearrangement by gripping the socket in one hand, and with the other hand, either directly gripping the bulb 15 or wedging the nails of the thumb and forefinger beneath the stop flange 18 to grip the latter. Yet, jarring or vibration of the lamp while in storage or use, will not loosen the lamp from its socket.
It is believed that the invention will have been clearly understood from the foregoing detailed description of my now-preferred illustrated embodiment. Changes in the details of construction may be resorted to without departing from the spirit of the invention and it is accordingly my intention that no limitations be implied and that the hereto annexed claims be given the broadest interpretation to which the employed language fairly admits.
What is claimed is:
1. A light comprising an electrically non-conductive socket member having an upper exposed socket cavity intersected at the bottom by a pair of longitudinal through bores extending to the base of the socket member, a first contactin one of said bores and a second contact in said socket cavity spaced from said first contact, a pair of power leads extending upwardly from the lower ends of said bores and connected to respective of said contacts, an electrically non-conductive plug member having a body portion seated in said socket cavity and an integral prong projecting downwardly from said body portion into the bore containing said first contact, and anupwardly projecting incandescent bulb seated in said body portion of the plug member and having a pair of filament leads extending downwardly therefrom, a first through said prong and a second through the base of said body portion in spaced relation to said pron-g, the free end of said first filament lead being doubled back over the bottomof said prong and pressed between said prong and said first contact, and the free end of said. second filament lead being doubled back over the base of said body portion and pressed between said body portion and said second contact.
2. The light of claim 1 in which said first contact comprises a ferrule receiving said prong in the upper end there of and the respective of said power leads in the lower end thereof.
3. The light of claim 1 in which said body portion of the plug member has a concave side face opposite said prong over which said second filament lead is doubled back, and in which said socket cavity has a convex face opposing said concave face and spaced by a gap therefrom, said second contact being housed in said gap.
4. The light of claim 3 in which said socket cavity has slots along the side edges ofsaid convex face retaining the side edges of said second contact.
References Cited by the Examiner UNITED STATES PATENTS 1,684,166 9/1928 Austin 339l84 X 2,572,382 10/1951 Peterson a 240-10 2,984,813 5/1961 Bossi 339-l76 X 3,104,924 9/1963 Capel 339176 X 3,182,185 5/1965. Ahroni et al. 240l0 NORTON ANSHER, Primary Examiner.-