Lamp Socket

Abstract

The following specification describes a lamp socket insulator having integrally formed cantilever extension walls for supporting a lamp electrically connected to a pair of wedge type electrical receptacles carried by the socket with a lamp housing engaged with the insulator in turn encircling and supporting the extension walls.

Description

This invention relates in general to instrument or panel type lamp sockets and more particularly to an improved arrangement for supporting a lamp in a socket of the type having wedge type electrical receptacles for receiving one end of a lamp.

In the prior art instrument of panel type lamp sockets having a wedge type electrical connection for the lamps, the lamp is cantilever supported by one end of the glass envelope inserted between metal spring fingers or legs. The lamp terminals projecting from the one end are folded over the lamp end and sandwiched between the spring fingers and glass end to complete the electrical connections. This type of arrangement leaves the lamp subject to considerable vibrational forces creating instability in the lamp connections.

The present invention utilizes a socket insulator of a type somewhat similar to that shown in U.S. Pat. No. 3,387,255. The socket carries a pair of wedge type electrical receptacles for in turn carrying the narrowed glass end of the lamp. The lamp terminals are short lengths of wire which are conventionally folded over a respective portion of the glass end and sandwiched between the respective receptacle and the glass end. The aforementioned patent discloses spaced annular portions for the socket insulator and in the present invention an inner cylindrical portion is provided with an extended wall to engage the lamp body at spaced peripheral positions and dampen the lamp vibration, while an annular housing which is also received by the insulator intermediate the cylindrical and annular portions in turn serves to support the extended wall.

It is therefore a primary object of the present invention to provide an improved socket insulator of the type having wedge type electrical receptacles for receiving a lamp.

Other objects and features will become apparent on examination of the following specification and claims together with the drawings.

FIG. 1 is an isometric exploded view of a lamp, socket and housing assembly employing the principles of the present invention;

FIG. 2 is a sectional view of the socket illustrating the lamp and receptacles assembled thereto;

FIG. 3 is an isometric view of the socket insulator partially in section; and

FIG. 4 is a bottom elevational view of the insulator socket.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In FIG. 1 of the drawings a lamp, socket and housing assembly is indicated by the reference character 10. The assembly 10 comprises a socket insulator 12 carrying a pair of spaced wedge type electrical receptacles 14 for receiving the rectangular portion 16 formed at the end of a generally tubular glass envelope defining a conventional wedge base lamp 18. A housing 20 encircles the lamp and an opening 22 at one end thereof provides a light exit for lighting an appropriate instrument or other apparatus to which the lamp assembly is attached by means of the spring clip 24 fixed to the housing and whose ends are snap fitted in an appropriate panel or instrument opening, for example.

The lamp terminals comprise a pair of spaced wires 26 which are folded back over the respective rectangular glass portion 16 for engaging against one of the spaced spring fingers or legs 28 of the wedge receptacles 14. The receptacles 14 are each provided with a terminal such as 30 at the end opposite the respective receptacles to which a respective insulated conductor 32 is connected for extending an electrical connection to the lamp 18 by means of a conventional socket 34.

The socket insulator 12 comprises a first annular wall 36 having a cleft therein and joined at the end adjacent terminal 30 to a cylindrical or annular wall 38 of smaller diameter so as to be inwardly spaced from wall 36 to define an annular passageway 40. The cylindrical wall 38 is provided with a pair of spaced U-shaped passageways 41 and 42. The passageways 41 and 42 are spaced by a central axially extending rib 44 from which a perpendicular arm 46 extends in opposite directions to define the legs of each U-shaped passageway 41 and 42.

Each U-shaped passageway 41 and 42 receives a respective U-shaped wedge type receptacle 14 with the side legs 28 of each receptacle 14 projecting beyond the central rib 44 to receive the bulb end portion 16. The short back leg of the respective U-shaped receptacle engages the back leg of the respective U-shaped passageway and a pair of spaced barbs 48 formed thereon engage opposite radial surfaces of arm 46 for preventing the retraction of the receptacle when inserted to the required position in a respective passageway 41 and 42.

A plurality of integrally formed circumferentially shaped arcuate walls 50 extend axially from an annular wall 52 formed on the periphery of wall 38 for receiving the tubular portion of the bulb 18. A locking lug 54 radially extending between walls 52 and 36 at spaced positions engages in a respective J slot such as 56 of housing 20. The walls 50 have an inner diameter of substantially 0.40 inch to grasp the 0.40 inch diameter wall of the bulb 18 for supporting the bulb against vibratory movement. The free ends of the walls 50 are thinned adjacent the free ends to facilitate insertion of the bulb and receipt of the housing 20.

The annular wall of housing 20 is received between the walls 36 and 50 and between 36 and 38 with the lugs 54 aligned with the axial portion of the respective J slot until the housing engages between walls 36 and 38 to abut an integrally formed circumferentially spaced stop such as 56 formed on the interior of wall 36. At that time the lugs 54 are at the axial end of the respective J slot so that rotation of the housing relative the insulator 12 serves to engage the lugs 54 in the circumferential portions of the J slots to prevent axial retraction of the housing. Thus, the walls 50 which extend substantially one-half the axial length of bulb 18, or about 0.4 inch beyond the end of wall 36, serve to support the bulb against vibratory movement. The annular wall of housing 20 in turn supports the walls 50 with the plastic preventing direct contact between the metal housing and glass bulb. The housing in turn is supported against vibration both by the circumferentially spaced stops 56 and lugs 54, while the attachment of clip 24 to an appropriate support assists in preventing relative movement between the bulb and receptacles.

The foregoing constitutes the description of an improved lamp socket and assembly whose inventive concepts are believed set forth in the accompanying claims.

Claims

1. A socket insulator assembly for receiving a lamp having a narrowed end from which a pair of terminals extend, the improvement comprising an insulator socket cylindrical wall having a pair of spaced axial passageways therein, an electrical receptacle in each said passageway with each receptacle having spring means adjacent one end for receiving said lamp narrowed end and establishing a respective electrical connection to a respective one of said terminals, a socket insulator annular wall encircling said cylindrical wall and spaced outwardly of said cylindrical wall for receiving a housing wall therebetween, means integrally joining said cylindrical and annular walls adjacent the axial ends of said socket walls opposite the position of said spring means receiving said lamp end, and integrally formed support means projecting from the end of said cylindrical wall adjacent said receptacle one end for engaging said lamp at peripheral positions intermediate the ends of said lamp for supporting

2. In the socket assembly claimed in claim 1, a housing having an annular wall for receipt between said socket cylindrical and socket annular walls with the diameter of said housing annular wall dimensioned for encircling engagement with said projecting support means to assist in preventing

3. The socket assembly claimed in claim 2 in which said insulator socket has a plurality of radial lugs integrally formed between said insulator socket cylindrical wall at a position spaced axially from said means joining said socket cylindrical and annular walls, a plurality of J slots formed at one end in said housing annular wall with each J slot receiving a respective radial lug, and a plurality of stop walls formed on said socket for engaging said housing wall one end and cooperating with said

4. In the socket assembly claimed in claim 3, a spring clip on said housing spaced from said housing one end for engaging said housing with a support.

5. In the socket assembly claimed in claim 4 in which said integrally formed support means comprises a plurality of circumferentially spaced arcuate walls projecting from said socket cylindrical wall along an inner diameter of 0.40 inch and substantially the same diameter as the outer diameter of said lamp.