Rectangular seal beam lamp and support with halogen bulb

A rectangular seal beam lamp unit with a high intensity halogen bulb, particularly adapted for utility vehicles, that is self-supporting without requiring any special mounting fixtures on the vehicle, and includes an entirely plastic reflector having an integral forwardly projecting hood that defines in part a recess that receives a rectangular lens sealed by an epoxy material. The halogen bulb has two rearwardly extending lead wires that are embedded in a synthetic rubber material in a recess in the rear of the reflector to assist in shock mounting the bulb. The bulb is primarily supported by a pair of curved resilient connector rods that are welded to the bulb lead wires at one end and curve downwardly to a connector and terminal assembly at the lower rear of the reflector. A strap surrounds the halogen bulb and is fixed to one of the resilient connector rods to support and shock mount the bulb in the reflector. The terminal assembly includes a pair of eyelets into which the ends of the terminal rods are soldered, that extend through and are staked to terminals in vertical slots on the reflector. Integral projections on the reflector extend rearwardly through the terminals to assist in holding them against the reflector. A universal mount for the lamp includes an integral downwardly extending spherical projection on the reflector.

BACKGROUND OF THE INVENTION 
Vitreous glass seal beam lamp units have been used for vehicle lighting 
since at least as early as the 1930's in the United States, These lamps 
include a parabolic reflector having a highly mirrorized inner surface 
that usually has two openings in the base portion that receive connectors 
for a filament aligned within the reflector. The reflector is enclosed by 
a circular convex lens also constructed of glass that is located with 
respect to the reflector by various types of integral locating tabs and is 
fused to the reflector by heat fusion. The connector assemblies are also 
connected to the reflector by a heat fusion process, and the content and 
pressure of gas within the reflector-lens envelope is carefully controlled 
through a filling tube formed integrally with the rear of the reflector 
that is fused after the evacuation and/or inert gas filling of the lamp 
envelope. 
Such a seal beam lamp unit is shown and described in the D. K. Right U.S. 
Pat. No. 2,148,314 dated Feb. 21, 1939. 
These seal beam lamp units, which by themselves are replaceable after the 
filaments burn out, require complicated locking rings and adjustment 
assemblies permanently carried by the associated vehicle to hold the lamp 
units in proper position. The locking rings frequently include adjusting 
brackets for varying the attitude of the lamp unit to properly direct the 
lamp's beam to effect the desired lamp alignment. 
These prior mounting arrangements and also the lamp units themselves, do 
not have any provision for shock-mounting the lamp or lamp filaments and 
efforts to devise them to attain shock-absorbing characteristics have been 
largely unsuccessful without eliminating the beam adjustment function of 
the mount. 
With the advent of rectangular seal beam lamp units, a shock-absorbing 
mount has been devised for a seal beam lamp that completely shock-mounts 
the lamp while at the same time permits limited attitude adjustments of 
the lamp's beam, namely a shock-absorbing mount for a rectangular seal 
beam lamp shown in the inventor's co-pending application Ser. No. 148,698 
filed May 12, 1980 now U.S. Pat. No. 4,345,307 entitled "Rectangular 
Headlamp Retainer" assigned to the assignee of the present invention. Even 
this mount, however, is quite costly and therefore forms a part of the 
vehicle itself and is not replaced at lamp burnout with the seal beam lamp 
unit itself. 
It has been suggested that the reflector of a rectangular seal beam lamp be 
constructed of a plastic material and that support flanges be formed 
integrally with the plastic material to eliminate the complicated mounting 
flanges and rings required in prior lamp units. Such a construction is 
shown in the Thomas T. Talon et al U.S. Pat. No. 4,188,655. This patent 
discloses three integral flanges on a plastic reflector that cooperate 
with three adjusting assemblies mounted to the vehicle that permit 
adjustment of the lamp beam in two orthogonal planes. While such an 
arrangement is suitable for many passenger automobile applications, it 
remains quite costly because of the three separate adjusting mechanisms 
required, and it does not provide for, nor can it accommodate any known 
effective shock-absorbing mechanism. 
It is a primary object of the present invention to provide a simplified 
replaceable seal beam lamp and support unit for utility vehicles that does 
not have the problems and disadvantages noted above in prior art seal beam 
lamp units. 
SUMMARY OF THE PRESENT INVENTION 
According to the present invention, a rectangular seal beam halogen bulb 
lamp unit is provided that is self-supporting and does not usually require 
any special mounting fixtures on the vehicle to which it is attached. The 
lamp unit is particularly designed for rugged use in utility vehicles, 
either on or off the road, in part through the provision of a unique 
shock-absorbing mount for the halogen bulb within the lamp unit. The lamp 
unit is designed so that it may be manufactured at a cost low enough to 
enable the entire unit to be discarded at the time the halogen bulb burns 
out or fails. 
Toward these ends, the lamp includes a one piece reflector molding 
constructed of an impact resistant plastic that has an integral ball 
extending downwardly forming part of a single point universal support 
assembly. The plastic reflector has a highly mirrorized coating on a 
paraboloidal inner surface that reflects light from the halogen bulb 
through a rectangular lens constructed of either plastic or vitreous glass 
material. An important aspect of the invention is that the reflector has 
an integral forwardly extending hood that minimizes light scattering from 
the high intensity halogen bulb in a very inexpensive and effective 
fashion. This hood also defines part of a rectangular forwardly facing 
recess in the reflector that receives a flange on the rectangular lens. 
This flange and an associated rim on the lens are epoxied into the 
reflector recess eliminating the costly fusion techniques that require 
careful control heretofore employed in fusing lens to vitreous reflectors. 
The halogen bulb, by itself conventional, has a pair of small gauge 
rearwardly extending lead wires that are embedded into a synthetic rubber 
material, such as silicone rubber, in an integral circular recess formed 
centrally in the rear of the reflector. This synthetic rubber embedding 
technique serves to maintain the aligned position of the halogen bulb 
within the reflector and also assists in providing a shock mount for the 
bulb. 
A terminal assembly is provided in the lower rear of the plastic reflector 
that includes downwardly projecting vertical terminals adapted to be 
received in a vehicle carried terminal connector. The halogen bulb is 
primarily supported and energized by a pair of curved resilient rods that 
are welded to the reflector lead wires and extend forwardly along the 
sides of the bulb and then curve downwardly to the terminal assembly. 
These rods are electrically conductive and provide the electrical paths to 
the bulb. A strap is attached to the base of the bulb and is welded to one 
of the rods to provide the main support for the bulb on the rods, and the 
resiliency of the rods provides vibration dampening for the bulb. 
The terminal assembly includes a pair of eyelet connectors that extend 
through and are epoxied into apertures in the lower rear wall of the 
reflector that receive and are soldered to the ends of the connector rods. 
The ends of these eyelet connectors project through openings in the 
terminals and are staked over to hold the terminals in position. To assist 
in maintaining the position of the terminals against the back of the 
reflector, integral projections on the rear of the reflector extend 
through secondary openings in the terminals and are heat fused over the 
terminals to hold them in position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawings and particularly FIGS. 1 to 3, a rectangular seal 
beam lamp unit 10 is illustrated fixed to a vehicle panel 13 without any 
special mounting brackets on the vehicle panel, and it is seen to 
generally include a one-piece molded plastic reflector 11 having a halogen 
bulb assembly 12 mounted therein, closed by a rectangular frontal lens 14, 
and having a universal mounting assembly 15 defined in part by a spherical 
projection 16 formed integrally with the reflector 11. 
As seen more clearly in FIG. 6, the rectangular lamp unit 10 includes a 
terminal assembly 17 at the lower rear of the reflector 11 that is adapted 
to be plugged into a two or a three hole terminal connector for supplying 
current to the halogen bulb assembly 12. 
Viewing the FIGS. 1 to 3 and 6, the reflector 11 is seen to be a generally 
rectangular one-piece plastic molding, constructed of an impact resistant 
plastic. The reflector 11 has a paraboloidal rear wall 18 that has a 
highly mirrorized reflective coating on its inner surface 19 that may be 
formed by a variety of commercially known mirrorizing techniques. The 
reflector 11 has slightly diverging top wall 20, bottom wall 21, side wall 
22 and side wall 23 extending forwardly from the rear wall 18. Walls 20, 
21, 22 and 23 have inner surfaces 25 merging with inner surface 19 of rear 
wall 18 that are also mirrorized in the same fashion. 
An integral hood 27 projects forwardly from the walls 20, 21, 22 and 23 and 
extends a significant distance forwardly of the lens 14 to reduce 
scattering of the high intensity light from the halogen bulb assembly 12. 
Hood 27 is rectangular in configuration and is defined in part by a 
peripheral shoulder 28 extending laterally outwardly from walls 20, 21, 
22, 23, and it has an outer wall 29 parallel to the optical axis of the 
reflector 11 and an outwardly tapered inner wall 30 providing an outwardly 
tapering configuration to the hood 27 itself when viewed in the 
cross-section of FIG. 6. 
The inner wall 30 of hood 27 forms part of a lens holding recess 32 for the 
lens 14. The recess 32 includes a peripheral lip 33 extending axially 
forwardly of the reflector walls 20, 21, 22 and 23. 
The lens 14 is generally rectangular in configuration and may be 
constructed of a clear or translucent vitreous or plastic material, and is 
seen to include a rectangular front wall 35 and a depending peripheral 
wall 36 having a reduced thickness flange 38 received over and loosely 
engaging the lip 33 of recess 32 in the reflector 11. The depending wall 
36 of the lens also has an outwardly projecting quarter round peripheral 
lip portion 40 adjacent the flange 38. The lens 14 is held to the 
reflector 11 by epoxy adhesive material 42 that fills recess 32 adhering 
to the rear and radially outer surfaces of flange 38, both sides of the 
quarter round lip portion 40 as well as a substantial portion of the 
surface 30 of hood 27. This securely locks and seals the lens 14 to the 
reflector 11 and aligns the lens with respect to the reflector in an 
accurate but simple fashion. 
The universal mounting assembly 15 is seen to include a generally U-shaped 
base bracket 44 having a spheroidal portion leg 45 that engages one side 
of spherical projection 16 on reflector 11, and a second leg 46 that 
threadedly receives an actuating rod 47 rotatably carrying a spheroidal 
clamping member 49 generally diametrically opposed to the spheroidal 
bracket portion 45 with respect to the center of spherical projection 16. 
Bracket 44 is clamped to vehicle panel by fasteners 50. 
By loosening actuator rod 47 and retightening it against the spherical 
projection 16 the lamp unit 10 may be positioned in any positioned with 
respect to two orthogonal planes intersecting the optical axis of the lamp 
unit, within the limitations imposed by the female connector (not shown) 
into which the terminal assembly 17 is inserted. 
The halogen bulb assembly 12 is shock mounted within the reflector 11 to 
increase bulb life and also to maintain the aligned position of the bulb 
assembly within the reflector for longer periods. The halogen bulb 
assembly 12 is seen to include a commercially available tungsten halogen 
bulb 52 aligned on the optical axis of the paraboloidal surface 19 of 
reflector 11, and it has a pair of parallel flexible lead wires 54 and 55 
extending rearwardly therefrom. The ends of the lead wires 54 and 55 are 
embedded into a synthetic rubber material 56 contained within a recess 57 
in the central rear of the reflector rear wall 18 defined by an integral 
annular rim or flange 59. The synthetic rubber material 56 may be silicone 
rubber for example. The embedding of the lead wires 54 and 55 of the 
halogen bulb in the synthetic rubber material 56 assists in providing a 
resilient shock mount for the bulb 52 and in aligning the optical axis of 
the bulb 52 with respect to the axis of the paraboloidal reflector surface 
19. 
Curved resilient spring connector rods 62 and 63 provide the primary 
support for the bulb 52 and also provide conductive paths between the bulb 
and the terminal assembly 17. The rods 62 and 63 are steel rods with a 
copper flash coating that have spring characteristics so that the bulb 52 
may vibrate with respect to the reflector and return to its originally 
adjusted or aligned position within the reflector when vibration ceases. 
Rod 62 has a horizontal leg portion 65 welded to bulb lead wire 54 
connected to a short vertical leg portion 66, a forwardly extending leg 
portion 67 and a curved downwardly and rearwardly extending leg portion 
69. Leg portion 69 continues to an end portion 70 that extends within and 
is connected to an eyelet 73 in the terminal 17 as seen in FIG. 11. 
The other connector rod 63 has a horizontal leg portion 75 welded to bulb 
lead wire 55, a forwardly extending portion 76 and a curved downwardly and 
rearwardly extending portion 77. Portion 76 continues to an end portion 79 
that extends within and is connected to an eyelet 80 in terminal 17 as 
seen in FIGS. 11 and 12. 
The bulb 52 is connected to and supported by the connector rod 62 by a 
strap 81 that surrounds the base of the bulb 52 and has an outwardly 
extending end 83 that is welded to the connector rod 62 at 84 as seen in 
FIGS. 2 and 5. Thus the rods 62 and 63 provide a resilient shock support 
for the bulb 52 and also the conductive paths to and from the halogen 
bulb. 
The terminal assembly 17 is a three terminal connector although only two 
are utilized in the embodiment of the invention illustrated in the 
drawings. 
As seen clearly in FIGS. 4, 6, 10 and 11, the terminal assembly 17 is seen 
to include a rectangular lug 85 formed integrally with the plastic 
reflector 11 that has three vertically arranged parallel slots 86, 87 and 
88 therein with slots 86 and 88 receiving vertical terminals 89 and 90. A 
third terminal would be provided in slot 87 for the three connector 
terminal arrangement. 
As each of the eyelets 73 and 80 along with their connections to the 
connector rod 62 and 63 and the terminals 89 and 90 is identical, 
reference will be made to the construction of the eyelet 80 and its 
associated parts as shown in FIG. 12 with the understanding that the 
eyelet 73 and its connection to the associated parts are identical. 
Viewing FIG. 12, the eyelet 80 is seen to include a reduced central portion 
92 epoxied to a bore 93 in terminal lug 85. Eyelet 80 has an enlarged 
inner portion 94 connected to the central portion 92 by a frusto-conical 
portion 96 seated against tapered counterbore portion 97 in bore 93. 
Frusto-conical portion 96 axially positions the eyelet 80 with respect to 
the lug 85. 
The rod end 79 is soldered to the outer end of the eyelet 80 by solder 
material indicated at 98 providing good electrical contact between the rod 
63, eyelet 80 and terminal 89, all of which are constructed of 
electrically conductive materials. The reduced central portion 92 of 
eyelet 80 extends through an upper hole 100 in the terminal 89 and is 
deformed over the terminal as indicated at 101 to hold the terminal in 
slot 86 and also to provide good electrical contact with the terminal. An 
integral post 103 extends from reflector lug 85 within terminal slot 86 
and projects through a second hole 104 in the termiinal. Post 103 has a 
head 106 formed by heat deformation that engages the outside of the 
terminal 89 and locks it properly in position. A similar post 108 is 
provided for terminal 90. 
As seen in FIGS. 10, 11 and 12, a rectangular cup-shaped plastic cover 108 
is provided for lug 85 that fits in a peripheral recess 109 on the lug 85 
and is held therein by an epoxy adhesive.