Socket

A socket for the reception of a bulb comprising a housing having an elongated cylindrical aperture for the acceptance of a multipurpose resilient grommet in sealing relationship, an electrically conductive wire extending through the central bore of said grommet, and an internal terminal strip that effects wiping of the conductive wire upon insertion and removal of a bulb.

BACKGROUND OF THE INVENTION 
The present invention relates to a sealed low profile socket for the 
reception of a bulb. The socket is used in an automotive brake light, tail 
light, parking light and turn signal systems, or the like. In addition, 
the improved socket has numerous uses and applications outside of the 
automobile industry. 
Sockets used in automobiles and other vehicles generally comprise a housing 
adapted to be securely fastened in a complementary aperture in a fixture. 
A bulb is releasably secured in the housing. At least one wire of a wiring 
harness of the vehicle is connected to a terminal of the housing 
internally thereof. The housing has one or more relatively movable 
terminals internally thereof for engagement with the contacts on the end 
of the light bulb. Springs are often provided to achieve the requisite 
"lost motion" to maintain contact pressure between the terminals of the 
housing and the light bulb. 
One problem with known sockets is that moisture and other foreign materials 
are able to enter the housing of the socket ultimately causing corrosion 
and failure of electrical contact between the bulb and the internal 
terminals of the socket. Attempts to solve this problem have generally 
required permanent sealing of the wire leading into the socket housing by 
epoxy or the like. While such practices insure positive sealing, service 
of the socket is rendered impossible and, upon failure thereof due to 
other circumstances, the entire socket must be replaced. Attempts to 
sealably yet removably attach the wires to the socket housing have 
heretofore failed. 
The present invention solves the aforementioned problem by utilizing a 
unique grommet that functions to both seal the wires leading into the 
socket housing, releasably support a wire contact within the housing that 
is engageable with an internal terminal of the socket, and provide a 
resilient lost motion connection between the wire contact and an internal 
terminal of the socket. Electrical contact betweend the wire contact and 
the internal terminal is "wiped" upon insertion of the wire contact 
thereby assuring positive electrical contact.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION 
As seen in FIG. 1 of the drawings, a sealed low profile socket 8, in 
accordanc with a constructed embodiment of the present invention, 
comprises a housing 10 adapted to be mounted in a complementary aperture 
12 in a fixture or receptacle wall 14. A sealing gasket 16 is disposed 
between the pheriphery of the aperture 12 in the receptacle 14 and housing 
10. A rear wall 17 closes the housing 10 and is sealably bonded thereto. 
The housing 10 is provided with an anti-indexing locking arm 18 that 
projects radially and circumferentially outwardly to engage a 
complementary shoulder 20 on the receptacle wall 14 thus holding the 
socket 8 in a locked position within the aperture 12. Conventional locking 
dogs 21 are provided on a cylindrical portion of the socket which are 
accepted through complementary apertures in the fixture wall 14 (not 
shown). 
As best seen in FIG. 3 of the drawings, a pair of rubber grommets 22 and 24 
are mounted in complementary holes 26 and 28, respectively, in the housing 
10. The grommets 22 and 24 have shoulders 30 and 32 thereon, respectively, 
that engage an inner surface 34 of the housing 10. In addition, the 
grommets 22 and 24 have shoulders 36 and 38 which engage complementary 
shoulders 40 and 42, respectively, adjacent an outer wall 43 of the 
housing 10. The grommets 22 and 24 are insertable through the holes 26 and 
28 by first lubricating the grommets and thereafter forcing them through 
the holes 26 and 28 whereupon the grommets are streteched so as to bias 
the shoulders 30, 32, 40 and 42 thereof into tight sealing engagement with 
their complementary surfaces 34 and 43. Disassembly of the grommets 22 and 
24 from the housing 10 can be accomplished by a pull thereon sufficiently 
strong to pull the shoulder 30 or 32 through its complementary aperture 26 
and 28. Normal tension on the grommet will not disengage the grommet from 
its aperture in the housing 10. Thus, the rubber grommets 22 and 24 are 
positively locked into the holes 26 and 28 and effect complete sealing of 
the housing 10 to exclude foreign contaminants therefrom. Also, the inner 
ends of the grommets 22 and 24 are compressible to augment contact 
pressure on inner terminals 58 and 68, as will be described. 
A pair of wires 50 and 52 extend through the center of the rubber grommets 
22 and 24, respectively, in sealed relation thereto. The wires 50 and 52 
are capped with button terminals 54 and 56, respectively, that make 
electrical contact with a pair of terminal strips 58 and 60, respectively, 
mounted internally of the housing 10. 
As best seen in FIG. 5, the terminal strip 58 comprises an arcuate end 
portion 62, a flat straight intermediate portion 64 and an arcuate end 
portion 66. Similarly, the terminal strip 60 has an arcuate end portion 
68, a straight intermediate portion 70, and an arcuate bulb contacting end 
portion 72 (see FIG. 4). 
A comparison of FIGS. 5 and 6 illustrates an important feature of the 
present invention. The terminal strip 58 has a first orientation relative 
to the housing 10 when a bulb is not present in the housing 10 as shown in 
FIG. 5. As seen in FIG. 6, insertion of a bulb 80 into the housing 10 
affects deflection of the intermediate portion 64 of the terminal strip 58 
so as to exert an outward bias on the bulb to maintain contact pressure 
thereagainst. It is also to be noted that, upon insertion of the bulb 80, 
the arcuate lower end portion 62 of the terminal strip 58 rotates slightly 
in the clockwise direction affecting wiping of the button contact 54 on 
the end of the wire 50. Removal of the bulb 80 from the socket 10 permits 
the intermediate portion 64 of the terminal 58 to return to its original 
configuration shown in FIG. 5 again affecting wiping between the end 
portion 62 of the terminal strip 58 and the button contact 54. The small 
but definite wiping movement of the end portion 62 of the terminal strip 
58 across the button contact 54 insures positive electrical connection 
therebetween which is renewed each time a bulb is removed from the housing 
10 or replaced therein. A similar wiping action takes place between the 
end portion 68 of the terminal 60 and its associated button contact 56. 
Another feature of the present invention is that depth of the housing 10 is 
minimized by orientating the flat terminals 58 and 68 so as to lie 
parallel to the base of the bulb 80. 
To assemble the socket 8, the socket housing 10 is first located face down 
in a holding fixture. Next, the bulb terminals 58 and 60 are laid into the 
housing 10 in their slot positions. The cover 17 is next placed on top and 
located with two pins which guide and hold it in position. The whole 
assembly is then placed under a sonic welder which welds and hermetically 
seals the cover to the body. 
The welded assembly is then removed from its holding fixture and the rubber 
ring seal 16 is placed over the socket neck and under the twist lock tabs 
21. This completes the socket 8. 
The housing 10 is a single piece plastic part, is color coded, and 
determines the socket's focal length. Single or double contact bulbs as 
well as even or odd "J" slots which retain the bulb 80 and can be 
accommodated as required by a desired application. 
To connect the socket 8 to the wires 50 and 52, the wires are slipped 
through the rubber grommets 22 and 24, stripped and terminated with the 
button terminals 54 and 56. This is preferably done when the wire harness 
is manufactured. The terminated wire and grommet assembly of the wire 
harness is smooth and soft, with no sharp edges or barbs to damage skin or 
clothing in handling. It is also resistant to damage from handling. 
The wire and grommet assemblies are then inserted into the holes 26 and 28 
provided in the socket housing 10. The grommets 22 and 24 should be 
lightly lubricated for ease of insertion. After insertion, the grommets 22 
and 24 position the button terminals 54 and 56 firmly against the terminal 
strips 58 and 60 and also complete sealing of the socket 8. 
Should the wires 50 or 52 be severly pulled or jerked after assembly to the 
socket 8, the wires 50 and 52 and grommets 22 and 24 will pull out of the 
socket 8 without damage to the button terminals, the grommets, or the 
socket, as the grommets are not a positive locking device. The grommets 
can be reinserted into the socket 8 without replacing or repairing any 
other part. 
From the foregoing description, it should be apparent that the socket of 
the instant invention is economical, easily assembled, has a flat low 
profile, and can be positively sealed to withstand the industry standard 
pressure test of 2 p.s.i. Since the socket is completely sealed and is low 
and flat, it can be made to fit and lock into any application hole. The 
connecting wires can be removed from the socket and replaced without 
breaking the socket or connectors. The wire sealing grommets maintain 
contact pressure against the socket terminal strips which also effect 
wiping of the button contacts on the wire upon insertion and removal of a 
bulb. 
While the preferred embodiment of the invention has been disclosed, it 
should be appreciated that the invention is susceptible of modification 
without departing from the scope of the following claims.