US2151882A - Electric connector - Google Patents

Description

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Patented Mar. 28; 1939 panier woo, sa Application October 20, 1934, Serial No. 749,I83 s claims. wi. ras-35s) This invention relates in general to electric connectors. and more particularly to electric sockets.

An electric socket ordinarily comprises a threaded brass shell which is electrically connected to one wire of an electric circuit, and a ilexible spring brass contacting member thereinelectrically connected to the other wire of the electric circuit. The spring brass contactor is contained centrally within the upper portion of the brass shell, and held therein by being mounted in a porcelain insulating plug, set in the upper open endL of the brass shell. In constructing such an electric socket, two things are of para- The spring contact must be electrically insulated from the shell which forms the other contact of an electric circuit to the lamp, and secondly, in order to provide a resilient contact for the light globe, this spring contact must permit a play of at least VM, so

. that the springiness thereof will follow the contact point on the lamp globe as the globe tends to move out of `contact by reason of vibration or other causes, and also to resiliently urge the lamp globe downwardly so that it will be tightly held within the threads of a brass shell which. forms the other contact of the electric circuit to the lamp. Y

In the manufacture of lamp sockets generally, the operation of securing the central spring contact to the porcelain plug member is attained with a very high amount of breakage, and therefore results in undue expense.

It is an object of this invention to provide an electric connector in which one of the contacts is imbedded in an insulating resilient material.

It is another object of this invention to provide a more economical electric lamp socket which is made of water-proof material.

It is another object of this invention to provide an electric lamp socket which has a unitary water-proof casing, said electric lamp socket having the contacts thereof insulatingly molded therein.

Numerous other objects and advantages will be apparent throughout the progress of the following specification.

Certain features of the ring closure means illustrated in Fig. 4 are not claimed herein as that comprises subject matter of applicants copending application Serial No. 748,251, iled October 13, 1934, which has matured into Patent No. 2,119,452-, issued May 31, 1938 in which the subject matter is claimed.

Several preferred embodiments of this invention are shown in the accompanying drawing, in

.which- Fig. 1 is a cross-sectional view of one embodiment of this invention.

Fig. Z is a cross-sectional view of another preferred embodiment.

Fig. 3 is a plan view of the embodiment shown Flgpll, llooking in the direction of the arrows Fig. 4 is another preferred embodiment of this invention.

In Fig. 1 is shown a selected embodiment of the invention which comprises a ilexible casing 23 made of molded rubber. On the top of this casing. and unitary therewith are extensions E and 1 respectively, which are molded around the electric conducting wires 9 and li respectively, making a water-tight joint therewith. The conductor 9 is electrically connected to a threaded brass shell 2i by the bared end of the conductor I3, which is soldered or otherwise electrically connected to the shell 2i at M. The other conductor -ii is connected 'to the other contactor point I9 of the socket. by a bared end of the conductor wire l5, which is inserted into a solderlled cavity I1 in the contactor point i9. The contactor point i9 is molded in the upper central portion of the socket casing. This contactor point has a flange i6 which serves to imbedthe contactor point I9 more securely .within the molded rubber. The contactor point i9 is furthermore provided with a shoulder 30 and a contact surface 3i. The shoulder 30 bears against the outer surface of the top part of the casing, and further aids in securing the contactor point within the rubber molded thereabout. The cas- Y ing 23 is so molded that the top of its interior portion 26 has a downwardly curved cross section. Within the rubber casing is operatively secured a threaded brass shell. The brass shell extends downwardly for a substantial distance from the top of the inside of the rubber casing to a point 24. The rubber casing continues downwardly from the end of the brassl shell and is flanged inwardly along an oblique surface 21 to an opening 29, said opening 29 being smaller in diameter than the diameter of the brass shell '2 I This is shown vwith greater particularity in Fig.`

3, the circle 29 being the bottom opening of the rubber casing. the circle 2i being an indication of the brass shell. When a lamp globe is screwed upwardly into the socket, the opening 29 being somewhat smaller than the shell, and naturally somewhat smaller than the screw cap portion o! the lamp globe, the rubber about the casing makes a tight connection with the lamp globe as it enters. As the lamp globe is screwed up into the brass shell, it nnally comes in contact with the surface Il of the contacter point i9. As the lamp globe is further propelled into the brass shell, the contactar point being -molded within resilient rubber, tends to give upwardly and permit the lamp to enter further into the brass shell, the surface of the rubber casing at the top of the inside, assuming a double bowed cross section such as shown at in Fig. 2, the rubber about the contactor point being compressed somewhat. When the lamp has finally been screwed up into the socket, the resiliency of the rubber casing about the contacter point tends to force the contactor point downwardly against the top of the lamp globe, which action serves to give a wiping contact between the contactor point and the central contact of the lamp, and furthermore to resiliently urge the lamp downward .against the threads of the brass shell, serving thereby to more securely hold the lamp within the socket. Finally, as the lamp tends to move down away from the contactor point i9 by reason of vibration and other similar factors, the resiliency of the rubber in which the contacter point is mounted, will urge the contactor point i9 downwardly so as to follow the central contact point on the lamp and maintain contact therewith, thus preserving the electric circuit unbroken. Inasmuch as rubber is a Very good insulating material, as well as a very good resilient medium, it serves to insulatingly separate the contactor point i9 from the brass shell 2|.

This avoids all diiiiculties previously encountered in manufacturing water-proof lamp sockets. since it is possible to strip or clean off a small portion of two insulated electric wires, insert ,one of the cleaned off portionsinto the contactar point cavity i1, and secure it thereto by an electric contact maintaining medium such as solder, secure the other electric conductor or wire to a brass shell in similar fashion. place the wires with their respective contact point and shell within a mold, and pour rubber into the mold. AfterA al lowingdzhe mold to cool and set, the finished socket may be taken therefrom and the rough edges left by the mold trimmed, if desirable. This eliminates entirely the operation of securing spring contacts for a porcelain plug for insertion in a brass shell, and results in a much more efcent and economical socket, which, at the same time, is thoroughly, water resistant and moisture proof.

Other embodiments of this invention may be made such as. for instance, that shown in Fig. 2, where the contacter point instead of bearing upon the rubber of .the casing by its shoulder as was described in connection with Fig. 1, is iltted with an auxiliary shoulder .32 for the purpose of securing greater bearing surface on the rubber. The socket may be further modied by extending the brass shell at 33 as shown in Fig. 4, and fashioning therein as an integral part thereof an annular metal ring of substantially semicircular cross section, into which ring may be inserted a rubber gasket or washer l1. In this last embodiment of the invention, the water resistant and moisture proof characteristics of the socket are dependent, at least at the point of contact with the lamp, upon the rubber washer 31 as shown in Fig. 4 rather than the rubber lip 28 as shown in Fig. 2.

Changes may be made in the form, construction and arrangement of the foregoing, without departing from the spirit or scope of the invention as set forth in the appended claims.

Whatisclaimedasnewanddesiredtobesecured by Letters Patent is:

1. A moisture-proof electric connector comprising a dielectric flexible resilient casing. a screw threaded shell imbedded therein, a central contact means imbedded therein, said central contact means being flexibly and insulatingly held from the shell by the material ofthe casing, said casing furthermore extending longitudinally outward from the open end of the screw threaded casing to form an extension portion, said extension portion oi.' the casing having formed on the inside thereof an annular groove, an annular metal shell disposed within said groove, said shell having a substantially semicircular cross section, and a resilient rubber ring or washer disposed within said metal ring.,

2. A moisture-proof electric connector comprising a dielectric resilient casing, a screw threaded shell imbedded therein, a central contact means imbedded therein, said central contact means being flexibly and insulatingly held from the shell by the material of the casing, said shell having formed integral therewith an extension portion disposed downwardly from the end of the screw threads thereof, said extension portion having formed therein an annular groove, said groove having a substantially semicircular cross section, and a washer or ring disposed within said groove, said washer or ring extending inwardly of the diameter of the screw threaded shell so as to form a resilient ring at the opening of the shell, said ring being of smaller diameter than the shell, whereby a water-tight connection is made when a lamp globe is inserted into the connector.

3. An electric connector comprising a molded resilient soft rubber casing, a threaded openended metal shell molded therein, lead-in wires molded in said casing, said casing being formed at the top with a downwardly extending arcuate surplus of the resilient rubber casing material, said surplus extending downwardly into the open top of the threaded metal shell, and a hanged vmetal contact member partially embedded in the rubber casing at the center of the downwardly extending surplus, said lead-in wires being respectively eonnectedto the flanged contact mem- `ber and the threaded shell, the resilience of the l molded rubber casing being such as to permit vmovement of the anged contact member upwardly and downwardly with respect to the threaded metal shell a distance approximately equal to the pitch of the threads in said threaded metal shell.

4. An electric connector comprising a molded, resilient, soft rubber casing, a threaded open; ended metal shell molded therein, lead-in wires embedded in said casing, said casing being formed at the top with a downwardly extending surplus of the resilient rubber casing material, said surplus `extending downwardly into the open top of the threaded metal shell. and a anged metal contact member partially embedded in the rubber casing at the center of the downwardly extending surplus, said lead-in wires being respectively connected to the flanged contact member and the threaded shell, the resilience of the molded rubber casing being such as to permit movement of the ilanged contact member upwardly and downwardly with respect to the threaded metal shell a distance approximately equal to the pitch of the threads in said threaded metal shell.

5. An electric connector comprising a molded, resilient, soft rubber casing having an opening to receive a lamp globe, a contact member in said opening and secured to said casing to engage the base of the lamp globe, lead-in wires embedded in said casing, said casing being formed at its top with a boss of the resilient, soft rubber Amaterial and extending downwardly into said opening centrally thereof, a second contact member secured to said boss substantially at the center of said opening, said lead-in wires being connected to said contact members, the resilience of the boss maintaining contact between the second contact member and the `central contact projection extending from the base of the lamp globe.

6. A combination of an electric light socket formed ci a -unitary piece of resilient, soft, rubber-like material to receive the shank of an electric light globe and having an integral boss extending inwardly centrally of the socket, said" boss y being resilient enough to support a contact member carried by said boss and to maintain contact between said member and the central contact of the lamp globe inserted in said socket, and a second contact member secured within said socket to contact the shank of said globe and to hold the shank of said globe in assembled relationship within saidsocket. l

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