US3581270A

US3581270A - Thermoplastic lamp holder

Info

Publication number: US3581270A
Application number: US813610A
Authority: US
Inventors: Larry L Shroyer
Original assignee: Lyall Electric Inc
Current assignee: Lyall Electric Inc
Priority date: 1969-04-04
Filing date: 1969-04-04
Publication date: 1971-05-25
Anticipated expiration: 1988-05-25

Abstract

A multiple lamp holder is disclosed which is characterized by its simplicity of construction. The lamp holder is made up of four pieces: two conductive terminals, an insulating bushing which holds the two terminals apart and an insulating housing which is molded in a single piece and consists of two complementary halves of the housing joined together in a hinged relationship so that the two halves may be folded together so as to enclose the terminals and bushing and the resulting structure need only to be sealed along a single seam.

Description

United States Patent [72] Inventor Larry L. Shroyer Wolcottville, Ind. [21] Appl. No. 813,610 [22] Filed Apr. 4, 1969 [45] Patented May 25, 1971 [73] Assignee Lyall Electric, Inc.

Albion, Ind.

[54] THERMOPLASTIC LAMP HOLDER 7 Claims, 5 Drawing Figs. [52] US. Cl 339/160, 339/62 [51] Int. Cl H01r 13/48 [50] Field of Search 339/160, 149,159,160,155 L, 199, 59, 60-63, 208, 210, 116; 174/92, 138.4

[56] References Cited UNITED STATES PATENTS 1,532,208 4/1925 Strongson 339/160 2,502,860 4/1950 Leithiser, Jr 18/59 3,072,875 l/l963 Johnson et al. 339/218X FOREIGN PATENTS 863,386 3/1961 Great Britain 339/62 Primary Examiner-Richard E. Moore AttorneyJeffers and Rickert PATENTEU "H25 I971 INVENTOR.

LAR'RY L. SHROYER THERMOPLASTIC LAMP HOLDER This invention relates to sockets for light bulbs and more specifically to a multiple bulb socket or multiple lamp holder.

Prior art lamp holders have the primary defect that they are relatively expensive to manufacture. They generally consist of a large number of parts and the assembly process is relatively difficult and costly. The prior art lamp holders have the further drawback that the shell contact, that is the portion that contacts the threaded portion of the light bulb has a relatively complex configuration and is difficult to fabricate. These and other disadvantages of the prior art lamp holders are overcome by the present invention which provides for a pair of relatively simple contacts which may be fabricated from flat sheet material. A simple nonconductive bushing is used to hold the two contacts apart and these three parts are enclosed in a one-piece nonconductive housing. This housing is initially molded in one piece having two complementary halvesjoined along one edge in a hinged relationship. Thus one of the halves may be rotated about this hinge with respect to the other half through 180 to form the socket housing. The housing then appears to consist of two halves joined along two seams, the first seam being the hinge portion. The second seam is then sealed, for example, by heating to form a completed socket assembly.

Accordingly, it is one object of the present invention to provide an economical socket structure.

It is another object of the present invention to provide a multiple lamp holder characterized by a minimum number of component parts.

It is a further object of the present invention to provide a method of manufacturing a multiple lamp holder which facilitates assembly of the holder.

It is another object of the present invention to provide an economical method of manufacturing a lamp holder.

These and other objects and advantages of the present in vention will be more readily seen from the following description given in connection with the accompanying drawing in 'which:

FIG. 1 is a perspective view of the assembled lamp holder;

FIG. 2 is a perspective view of the partially assembled lamp holder;

FIG. 3 is an end view of the lamp holder;

FIG. 4 is a cross-sectional view taken along the line 4-4 of FIG. 5; and

FIG. 5 is a cross-sectional view taken along the line 5-5 of FIG. 3.

Referring first to FIG. 1 the completed lamp holder or bulb socket is seen to consist of a pair of terminals I and 2 exterior of the housing 3 which form a male plug. The socket has a threaded aperture 4 into which a bulb or lamp is to be inserted. The specific structure of the socket is most easily seen in FIG. 2 which shows the interior portion of the housing including two threaded

apertures

4 and 5. The socket is seen to contain two conductors, the first conductor comprising a single smooth, curved, resilient, conductive strip portion 7 and a prong portion I. The second conductor is seen to comprise a prong portion 2 and a central portion 8 which is adapted to simultaneously Contact a pair of base terminals of a pair of bulbs which would be threaded into the two apertures. FIG. 2 shows the two complementary halves of the nonconductive lamp housing being joined along the dotted line 6. The two halves may be joined along the entire length of the straight line 6 or may be joined along only portions thereof. In either event this line 6 acts as a hinge so that one-half of the housing may be revolved about the straight line 6 through 180 so as to close and give the appearance of the completed socket of FIG. 1. When hinged shut inthis fashion, there is seen to result two

seams

9 and 10 as illustrated in FIG. 3. The seam I0 is seen to require no further attention since the hinge portion 6 holds it shut. The seam 9 is heated or otherwise sealed so as to hold the housing shut in its final form.

Returning now to FIG. 2 the first conductor is seen to have been formed from a T-shaped flat piece of conductive material by bending the base of the T through 90 and the second conductor is seen to have been formed from a different (taller and less wide) T-shaped flat piece of conductive material by bending each of the symmetrically oppositely extending portions of the T upwardly through Tlhus either of these conductors may be fabricated by the relatively simple process of stamping out a T-shapcd piece from flat stock material and performing one simple 90 bending operation in the case of the shell contact and two simple 90 bending operations in the case of the base contact. Additionally, these conductors may be provided with holes which will allow them to pass over and be aligned by the

pins

11 and 12 which are integral parts of the lamp housing. A cylindrical insulating bushing 13 as shown in FIG. 4 may optionally be provided to separate and hold the two conductors down on the

pins

11 and 12.

Referring now to FIG. 5' the curved shape of the conductive strip 7 is readily apparent. This curve provides a spring action when a bulb is screwed into either of the

apertures

4 or 5. Assume for the moment that a bulb has been screwed into aperture 4. It's center base terminal will be in contact with the left side of the central portion 8 and its shell contact will be touching the left part of the conductive strip 7. The spring action of the conductive strip 7 will hold the shell or threaded portion of the bulb securely in the threaded portions of the nonconductive housing.

The two conductors may be fabricated from any suitable metallic conductor. The nonconductive housing may be made ofa thermoplastic material which will allow the seam 9 of FIG. 3 to be easily sealed by heating the seam. A thermosetting plastic material such as nylon has been found suitable for one embodiment of this invention. The cylindrical insulating bushing may be made from a similar material and in one embodiment of the present invention teflon was used for this bushing. The threaded portion of the housing could be constructed so as to accept a bayonet base bulb.

In lieu of the cylindrical bushing illustrated as a separator for the two conductors, a potting material such as epoxy could be caused to flow between the conductors to provide a moisture proofseal.

The lamp holder mounting configuration illustrated could be modified to conform with any mounting surface or aperture therein.

The prong portions of the conductors could be terminated within the housing, leads affixed thereto, and the leads then caused to protrude exterior of the housing. Therefore, while the invention has been described with reference to a particular embodiment it is to be understood that modifications may be made without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

I. A multiple bulb socket comprising;

a nonconductive housing formed with two threaded apertures and having an interior and an exterior portion;

a pair of terminals exterior of said housing forming a plug;

a first T-shaped conductor which has been deformed in a first way comprising a single smooth curved resilient conductive strip portion interior of said housing adapted to connect together a pair of shell contacts of a pair of bulbs and a prong portion extending to the exterior of said housing to form one of the pair of terminals;

a second T-shaped conductor which. has been deformed in a second way comprising a prong portion extending exterior of said housing forming the second of said pair of terminals and a central portion interior of said housing adapted to simultaneously contact a pair of base terminals of a pair of bulbs; and

an insulating bushing having ends which engage and separate said first and second conductors.

2. The socket of claim 1 wherein said nonconductive housing comprises a single molded piece of thermoplastic material.

3. The socket of claim I wherein said insulating bushing is a hollow cylindrical bushing further comprising a pair of alignment pins, each said pin extending through one conductor and into one end of said hollow bushing.

4. A method of manufacturing a multiple lamp holder comprising:

molding, in a single piece, the two complementary halves of the nonconductive lamp housing;

forming and inserting a first and a second conductor, said step of forming and inserting comprising; forming the first conductor from a T-shaped flat piece of conductive material by bending the base of the T upwardly through substantially a right angle, forming the second conductor from a different T-shaped flat piece of conductive material by bending each of the symmetrically oppositely extending portions of the 'l' upwardly through substantially a right angle, and inserting each of the so-deformed conductors into the lamp housing;

providing a basing with ends engaging and separating said first and second conductors;

folding said complementary halves together; and scaling the resulting seam.

5. The method of claim 4 wherein the step of sealing comprises:

heating the vicinity of the seam so as to fuse the material in the vicinity of the seam.

6. A method of manufacturing a multiple lamp holder comprising: i

molding, in a hinged relationship, the two complementary halves of the nonconductive lamp housing; forming and inserting a first and a second conductor, said step of forming and inserting comprising; forming the first conductor from a T-shaped flat piece of conductive material by bending the base of the T upwardly through substantially forming the second conductor from a different T-shaped flat piece of conductive material by bending each of the left and right portions of the T upwardly through substantially 90, inserting each of the soformed conductors into the lamp housing, and providing a bushing with ends engaging and separating said first and second conductors; folding said complementary halves together; and sealing the resulting seam. 7. The method of claim 6 wherein the step of sealing comprises heating the vicinity of the seam so as to fuse the material in the vicinity of the seam.

Claims

1. A multiple bulb socket comprising; a nonconductive housing formed with two threaded apertures and having an interior and an exterior portion; a pair of terminals exterior of said housing forming a plug; a first T-shaped conductor which has been deformed in a first way comprising a single smooth curved resilient conductive strip portion interior of said housing adapted to connect together a pair of shell contacts of a pair of bulbs and a prong portion extending to the exterior of said housing to form one of the pair of terminals; a second T-shaped conductor which has been deformed in a second way comprising a prong portion extending exterior of said housing forming the second of said pair of terminals and a central portion interior of said housing adapted to simultaneously contact a pair of base terminals of a pair of bulbs; and an insulating bushing having ends which engage and separate said first and second conductors.

3. The socket of claim 1 wherein said insulating bushing is a hollow cylindrical bushing further comprising a pair of alignment pins, each said pin extending through one conductor and into one end of said hollow bushing.

4. A method of manufacturing a multiple lamp holder comprising: molding, in a single piece, the two complementary halves of the nonconductive lamp housing; forming and inserting a first and a second conductor, said step of forming and inserting comprising; forming the first conductor from a T-shaped flat piece of conductive material by bending the base of the T upwardly through substantially a right angle, forming the second conductor from a different T-shaped flat piece of conductive material by bending each of the symmetrically oppositely extending portions of the T upwardly through substantially a right angle, and inserting each of the so-deformed conductors into the lamp housing; providing a basing with ends engaging and separating said first and second conductors; folding said complementary halves together; and sealing the resulting seam.

5. The method of claim 4 wherein the step of sealing comprises: heating the vicinity of the seam so as to fuse the material in the vicinity of the seam.

6. A method of manufacturing a multiple lamp holder comprising: molding, in a hinged relationship, the two complementary halves of the nonconductive lamp housing; forming and inserting a first and a second conductor, said step of forming and inserting comprising; forming the first conductor from a T-shaped flat piece of conductive material by bending the base of the T upwardly through substantially 90*, forming the second conductor from a different T-shaped flat piece of conductive material by bending each of the left and right portions of the T upwardly through substantially 90*, inserting each of the so-formed conductors into the lamp housing, and providing a bushing with ends engaging and separating said first and second conductors; folding said complementary halves together; and sealing the resulting seam.

7. The method of claim 6 wherein the step of sealing comprises heating the vicinity of the seam so as to fuse the material in the vicinity of the seam.