United States Patent [1 1 [Ill 3,885,185
Tilley 1 1 May 20, 1975 1 INCANDESCENT LAMP 1 71 ABSTRACT 1 ll 33 E. S th [76l Inventor #22:; g a 85 84] 1 I An incandescent lamp having a bulb and a male base at the trailing end thereof for placement in a conven- [ZZl Flledl 1974 tional threaded electrical socket, the male base com- App]. No.: 456,097
[52] U.S. Cl 313/318; 313/315; 339/91 L; 339/242; 339/258 R [51] Int. Cl H01] 5/48; HOlj 5/50 [58] Field of Search .1 313/315, 318; 339/242, 339/258 R, 258 P, 91 L [56] References Cited UNITED STATES PATENTS 2.081743 7/1937 St. Louis 313/318 X 2.132.578 10/1938 ReichelM... 313/318 X 2,848,643 7/1958 Spataro r i 313/318 3,040,285 6/1962 Stanley 339/258 R 3,050.705 8/1962 Benson 339/258 R 368L741 8/1972 Spezialfabrik 339/258 R 3,723.836 3/1973 Oulman et a1. 339/258 R Primary Examiner-Saxfield Chatmon, Jr. Attorney, Agent, or Firm-Lynn G. Foster prising a ring conductor secured to the necked down portion of the bulb and from which a plurality of electrically conductive resilient fingers rearwardly extend. the unrestrained composite diameter of the resilient fingers being less than the inside diameter of the conventional electrical socket. A second axial conductor projects rearwardly from the base of the lamp. being insulated from the ring connector by suitable dielectric whereby the male end of the lamp may be linearly inserted into the socket causing constriction of the tingers creating a firm electrical connection with the threaded peripheral conductor of the socket, the axial conductor of the lamp coming to rest against the exposed spring of the axial conductor of the socket whereby electrical energy is communicated to the filament of the lamp.
4 Claims, 3 Drawing Figures FATENTED HAYZOIHYS INCANDESCENT LAMP BACKGROUND 1. Field of Invention The present invention relates generally to the field of artificial light and more particularly to an improved male base at the trailing end of an incandescent lamp for linear placement in a conventional. threaded electrical socket.
2. Prior Art Many past proposals have been made for electrically connecting the male end of an incandescent lamp to an electrical socket. The standard for many years has been a lamp with a threaded trailing conductor and a trailing axial conductor separated by a suitable dielectric layer. The threaded lamp is screwed into and out of the conventional socket.
Alternatives have consisted of lamps each with a specially configurated male conductor end to be united with a specially configurated (non-standard) electrical socket. No proposal has been made for placement of an incandescent lamp rectilinearly into a standard threaded electrical socket.
BRIEF SUMMARY AND OBJECTS OF THE PRESENT INVENTION The present invention comprises an economical incandescent light bulb which is linearly press-fit into a conventional threaded electrical socket thereby eliminating the need to thread a bulb into said socket. The light bulb comprises one peripheral conductor at the reduced diameter trailing end of the bulb, having rearwardly directed resilient fingers biased radially outwardly and having an unrestrained composite diameter greater than that of the socket, the fingers being mounted to the glass of the bulb and inwardly radially displaceable counter to the memory of the fingers upon entry of the fingers into the threaded socket to firmly retain the connection.
Accordingly, it is a primary object of this invention to provide an improved incandescent light bulb to be linearly press-fit into and releasably retained in a conventional threaded electrical socket.
It is another paramount object of the present invention to provide an electric light bulb one conductor of which is disposed at the reduced diameter trailing of the bulb comprising rearwardly directed resilient conductive fingers radially biased outward having an unre strained composite diameter greater than the diameter of a conventional threaded electrical socket to accommodate radial deflection inwardly of the fingers whereby the bulb becomes releasably press-fit into the socket by axial insertion.
These and other objects and features of the present invention will be apparent from the following detailed description, taken with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective representation of a presently preferred light bulb configuration according to the present invention;
FIG. 2 is an enlarged side elevation view with parts broken away for clarity of the light bulb of FIG. 1 disposed adjacent a conventional electrical socket; and
FIG. 3 is a side elevation view similar to FIG. 2 but showing the light bulb in press-fit electrically conducting relation with the socket.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT Reference is now made to FIGS. l-3 which illustrate the structure and use ofa presently preferredincandescent light bulb 10 according to the present invention Conventionally, the incandescent lamp l0 comprises aglass bulb 12 in which a filament is disposed. The glass bulb I2 is necked down or of reduced transverse diameter at the trailingend 14 thereof. the trailingend 14 being bonded or otherwise suitably physically attached to aring conductor 16. The ring connector I6 is electrically connected to one end of the filament within the glass bulb l2 and comprises anannular collar 18 from which a plurality of rearwardly extendingconductive fingers 20 project. Each finger is radially biased outwardly and rearwardly to a maximum diameter d. (FIG. 2), which is of considerably greater magnitude than the diameter d of a conventional threadedelectrical socket 22.
Each finger also curls inwardly at itstrailing end 24 to (a) prevent free end interference upon insertion into or removal from thesocket 22, (b) restrict the amount of deflection experienced by eachlinger 20 by reason of contact with the rearwardly extending centralrefractory separator 26 and (c) prevent electrical contact with the central socket conductor. Therefractory separator 26 is stepped in diameter at radially directed portion 28 and comprises a relatively large annular wall 30 superimposed against and insulating thefingers 20 from a secondaxial conductor 32, the exposed end of which is also electrically insulated by a reduceddiameter wall 34 of therefractory separator 26.Conductor 32 is electrically connected to the other end of the filament.
As mentioned, thesocket 22 is conventional comprising a dielectric body 36 a peripheral threadedconductor 38, the diameter across the root of the threads being designated d and comprisingaxial socket conductor 40 connected to a conductive exposed U shapedspring 42.
In use, theincandescent lamp 10 is advanced linearly and essentially axially into initial contact with and ulti mate into retained press-fit relation within thesocket 22, with theconductor 16 becoming disposed in electrical contact with the peripheral threadedconductor 38 andconductor 32 in electrical contact with thespring 42. Insertion results in a constriction of the com posite diameter from d by deflection ofthe radiallybiased fingers 20 to a composite diameter equal to the socket diameter (1 Thefingers 20 exert an outward bias against thesocket 22 when located within thesocket 22 to retain in the inserted condition against inadvertent removal. The assembled condition is illustrated in FIG. 3. This approach allows for linear insertion ofa bulb in a conventional socket which is benefi' cial to the infirmed and useful when a socket is located in a hard to reach place.
The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the fore going description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
What is claimed and desired to be secured by United States Letters Patent is:
1. An incandescent lamp for rectilinear insertion into press-fit conducting relation with a conventional threaded electrical socket comprising:
a bulb having an axis. the bulb containing a filament and having a necked down trailing end;
first conductor means connected to one end of the filament and mounted to the necked down trailing end of the bulb, said first conductor means comprising a plurality of axially extending, rearwardly directed, and outwardly radially biased resilient conductive fingers with memory, each finger being initially resiliently biased a predetermined radial distance from the axis of the bulb to form an initial composite diameter greater than the diameter of said threaded socket;
second conductor means carried in exposed relation gers are each joined to a conductive ring carried at the trailing end of the bulb and comprising said first conductor means.
3. The incandescent lamp of claim I wherein each finger is inwardly curved so that the free end thereof is situated well within said composite diameter.
4. The incandescent lamp of claim 1 wherein said electrically insulating means is stepped.