US3510718A - Incandescent lamp - Google Patents

Description

J. J. VETERE INGANDESCENT'LAMP Filed Nov. 6. 1967 May5, 197 0 JOHN J., VETERE INVENTOR ATTORNEY Patented May 5, 1970 3,510,718 INCANDESCENT LAMP John J. Vetere, Beverly, Mass., assignor to Sylvania Electric Products, -Inc., a corporation of Delaware Filed Nov. 6, 1967, Ser. No. 680,855 Int. Cl. H01j /48, 5/00 US. Cl. 313-318 4 Claims ABSTRACT OF THE DISCLOSURE Tungsten-halogen lamps have been previously used in the automotive fields as accessory lamps, but recently new applications have been adopted. One recent use of the tungsten-halogen lamp is in automotive headlight assemblies. Due to this new application, increasing demands have been put on the lamp manufacturer to develop lamps and fixtures for racing vehicles. Some of the requirements demanded fixtures with a multitude of design factors, such as, the use of scaled reflectors with various combinations of lenses. Also the lamp had to have a singleended mechanical base with a pre-focus adaptability and provided with a single electrical spade contact. These design variations produced an interchangeable lamp with the desired light output and controlled light patterns necessary for night racing.

Although adequate light patterns were achieved with these designs, featuring the tungsten-halogen lamp, the high temperature generated by the lamp produced other problems. Two major problems encountered due to this excessive heat in the base area of the lamp are: insulation break-down and separation of the electrical spade contact from the side covers. Under the condition of competitive night racing, where continuous illumination is required, these problems become of prime importance.

In the basing of a lamp with the above-mentioned specifications, certain assembly steps must be performed. A lamp of this type is provided with a press-seal with an I-shaped cross section at one end where the filament leadin wires are directed out beyond the seal. To provide a mechanical base for the lamp, a pair of metal seal cover plates are utilized to cover the press-seal area. The seal covers extend below the seal and provide a housing for an insulated spade contact and also to support an alignment disc for insuring coil alignment in each fixture.

To provide an electrical connection to the lamp, one of the filament lead-in wires is attached to the inside of a seal cover plate while the other lead-in wire is attached to the top edge of the spade contact. After this operation, the side plates are welded together over the press seal. The aligning disc is then slid over the joined side plates and is fastened in place at a point just short of the end of the press seal.

An insulating material, usually of epoxy-resin composition, is then placed in the area around the contact spade, for the purposes of separating and insulating the spade from the side covers. After the epoxy-resin has setup or hardened, a pinch or staking operation is then performed to the outside of the cover plate extensions at a point adjacent to the new potted spade, this operation pinches the side covers into the insulation.

The above-described fabrication provided based lamps with adequate specifications in the lower wattage range. But due to increased speeds in the racing fields, higher illumination for deeper track penetration was needed. When lamps of increased wattage were utilized in this field, the heat problems previously mentioned were fostered.

. Part of the heat generated by the lamp filament settled in the base area. During continuous normal operation, when the lamp is fixed within a weather-sealed fixture, the heat build-up in the seal area gradually weakened the holding qualities of the epoxy insulator. Thus, because of break-down of the insulator the rough service to which the lamp will be subjected, short circuits sometimes 00- our between the contact spade and the cover plates. Also, during replacement of the lamp, separation sometimes occurs between the spade and the base. These problems required longer pit-stops for the racing vehicle.

I have overcome these problems by providing a lamp base with positive locking features built around the contact spade. I also provide an insulator for the spade that retains its workable characteristics, even under these high lamp operating temperatures.

Included in the construction are side covers, an alignment disc, insulator material and a spade contact. By redesigning the normally flat contact spade so as to form an enlarged build-up ledge, an enlarged pressure area between the spade and the side covers can be made. A preformed Teflon insulating sleeve is fitted over the spade in place of potting material previously used to entirely isolate the metal contact spade from the side cover. A clearance hole through the ledge and the cover plates is provided for the insertion of an insulated rivet which will positively hold the insulated contact spade to cover plates. Not only does the rivet firmly hold the spade in place, but by virtue of the raised ledge, compression will be greater between the spade and the covers.

Other features, advantages and objects of the invention will be apparent from the following description taken in connection with the accompanying drawing in which:

FIG. 1 is an exploded view of the pertinent components of the invention; FIG. 2 is an elevational view of a completed lamp and base, and FIG. 3 showed another form of the contact portion of the base.

Referring to FIG. 1, a lamp assembly is shown in a pre-assembled orientation. The lamp 4 of vitreous material is provided with a conventional I-shaped press-seal base 6 having a pair of lead-in wires 8 extending beyond the seal. According to the present invention, a locating node 14 has been disposed on each side of the flat surface 13 of the press-seal. The node is centrally located between the raised edges 12.

To provide a mechanical spade-type base for this particular press-seal, I incorporate a pair of mating cover plates 16. Each cover plate is pre-stamped to coincide with the shape of one-half of the side of the base 6. That is, the plates are deformed with a pair of grooves 18 that fit over the raised edges 12 of the press-seal and extend beyond the edges terminating in Wing extensions 19. Centrally located between the grooves 18 on each plate 16 is a horizontally elongated slot 20. The purpose of the slot is to receive the glass node 14 of the press-seal for locating and holding the lamp in a prescribed coil to base arrangement. The shape of the slot 20 allows only lateral adjustment of the plates 16. The plates 16 extend below the groove 18 approximately the same distance as the length of groove 18 and are provided with inner directed cars 22. Located on the lower part of each plate and equidistant the ears 22 is a hole 24, the purpose of which will be described hereafter. Another component of the base structure is an alignment disc 26 provided with a centrally located slot 28 on its top surface. The slot is formed by displacement of the surface to form a pair of upstanding ears 30 defining two long sides to the slot 28. At pre-calculate-d positions on the top of the disc are two upstanding studs 32 located for maintaining the lamp in an aligned operative position. A portion of the disc 26 is cut away to define a locating edge 36, to coincide with a conventional socket.

An electrical flat spade 40 having a raised ledge 42, heavier than the basic tong portion of the spade, the top part of the ledge is reduced down to define a small upstanding tab 46. An orifice or clearance hole 48, similar in size to the holes 24 in the side covers, is located through the ledge portion.

The above-mentioned components are the major structural parts of the base with the exception of a Teflon fiat insulator sleeve 50, a rivet 52 and a circular Teflon insulating sleeve 54. The flat sleeve 50 is utilized to isolate the spade 40 from the side cover 16 and the circular sleeve 54. -It insulates the rivet 52 from contact with the ledge portion of the spade.

The assembly steps taken in this new improved lamp base are similar to that previously mentioned. The upstanding ear 46 of spade 40 is connected to one of the lead-in wires 8 by a solder or weld operation while the other lead-in wire is bent to a position where it contacts a side cover 16 and is also welded in place. The side covers 16 are then fixed over the press-seal portion of the lamp and secured in place by a weld applied to the wing extensions 19. In this fixed position the side covers completely encompass the press-seal with the exception of the node 14 of the press-seal which is located within the elongated slot 20. The node and slot arrangement maintains a coil-to-base relationship of the lamp and also locks the covers 16 to the press-seal. With the covers 16 in place, the flat Teflon sleeve 50 is then slid over the raised ledge 42 of the spade 40 to completely isolate the side covers 16 from the spade.

Only two minor operations remain to complete the lamp assembly, one is the attachment of the locating disc 26 over the side covers. This is accomplished by sliding the disc 26 over the cover extensions to a point short of the end of the grooves 18, where the disc is firmly secured by a weld or other similar fastening means. To finish this assembly, the Teflon circular sleeve 54 is inserted through the orifices 24 in the covers 16, through a mating hole 51 in the Teflon sleeve and hole 48 of the ledge 42. The rivet 52 is then passed through sleeve 54 and crimped to firmly secure the spade 40 to the side covers 16.

In FIG. 2 a completed lamp is shown and the positions of the component parts as described previously. In FIG. 3, a form of spade is shown which might be used where speed in changing the lamp is not as essential as in racing. In this, the spade 40 has the bent portion 41 for providing contact.

It is apparent that modifications and changes may be made within the spirit and scope of the instant invention but it is our intention however only, to be limited by the appended claims.

I claim:

1. An incandescent lamp base comprising: a sealed envelope of vitreous material having a press-seal portion of generally I-shaped transverse section, said press-seal provided with a locating means thereon; a pair of lead-in conductors hermetically sealed through and extending beyond said press-seal; a pair of metal cover plates, each of which coincidental to the other disposed about said press seal and extending beyond the lower end thereof; said cover plates fitting over said locating means; alignment means disposed about said cover plates and attached thereto; a conductive metal spade disposed within the lower portion of said seal plates and attached to one of said lead-in conductors; a raised ledge disposed on said spade and within said cover plates; insulating means disposed about said spade between said cover plates and said spade; locking means positioned through said cover plates and said raised ledge of said spade to firmly hold the spade and cover plates in a fixed position.

2. The lamp according to claim 1 wherein said alignment means is a disc.

3. The lamp according to claim 2 wherein said pressseal portion is of I-shaped transverse section.

4. The lamp according to claim 2 wherein said lamp envelope contains an iodine fill.

References Cited UNITED STATES PATENTS JOHN W. HUCKERT, Primary Examiner A. I. JAMES, Assistant Examiner U.S. Cl. X.R. 313-317, 331

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