Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This application relates generally to flashers
for vehicle lights and more particularly to an improved method
and apparatus for assembly and sealing the components of such
an apparatus.
In the use of high intensity flashers, such as
are used on school buses, farm machinery and the like, a
problem has been present, in that water damage is the common
cause of failure of the electrical components. These devices
are commonly subjected to moisture from the environment. In
the case of school buses, the flashers are commonly mounted
under the dashboards, and the interior of the buses are fre-
quently washed with a hose, whereby the flashers become sub-
jected to water damage.
In general, the present invention comprises a
novel flasher apparatus, and method of making same, wherein a
main housing is used to form a cavity for enclosing the circuit
board. A mounting strap for securing the device to the vehicle
frame is formed of electrically conductive metal and provided
with an internal ground connection that plugs into a ground
~20 connection on the circuit board; as well as an external mount- ~
~ ing flange that serves the additional function as the external ~ -
; ~ ~ qround connection for the control circuit. A potting material,
such as an epoxy resin, is poured into the cavity in sur-
rounding relationship with the circuit board and internal por-
tion of the ground strap, so as to provide a positive weather-
proof seal for the electrlcal components, as well as means for
securing the mounting strap to the housing.
As another aspect of the present invention, a
secondary housing is provided for mounting an electrical com-
ponent, such as a relay connected to the circuit board, and
such secondary housing is sealed and secured to the above
mentioned resinous material.
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As still another aspect of the present invention
to provide a flasher apparatus of the type described wherein
the control circuit board is provided with up-standing con-
nectors which extend to the exterior of the main housing to
form plug connectors, and which are embedded in the resinous
material, so as to be sealed and reinforced thereby.
It is therefore a primary object of the present
invention to provide a novel flasher apparatus, and method of
fabricating same, wherein the components are assembled in a
unique manner, so as to provide positive moisture protection
for the electrical components.
It is another object of the present invention to
provide an apparatus of the type described wherein the com-
ponents are secured together with high structural integrity.
The invention is particularly directed toward a
controller for vehicle lights comprising: in combination a
circuit board housing including spaced side walls and a bottom
'~ wall forming a cavity; a circuit board positioned in the cavity
and including a circuit board ground terminal and an electri-
~, 20 cally conductive mounting and grounding means including an
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internal flange forming a second ground terminal engaging the
circuit board ground terminal. An intermediate flange extends
- to the exterior of the cavity, and an external flange extends
,~ beyond a side wall and forms a housing supporting mount for
connection with a vehicle in grounded relationship therewith.
.i, A resinous insulating and sealing material is provided within
, ~
the cavity in sealed surrounding relationship with the engaging
ground terminals.
The invention is also particularly directed toward
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' 30 the steps in the method of fabricating an electrical controller
for a light flasher system. The method comprises positioning
a circuit board within the cavity of a cup shaped circuit board
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housing, with the board including a circuit board ground
terminal; and positioning a conductive mounting strap adjacent
to the circuit board housing with an internal flange portion
of the strap in contact with said circuit board ground terminal,
an intermediate flange portion of the strap extending to the
exterior of the cavity, and an external flange portion of the
strap extending beyond a side wall of the housing and forming
a shoulder for mounting and grounding the controller. The
cavity is then filled with a dielectric potting compound so as
to surround the circuit board and secure the mounting strap to
the circuit board housing.
Further objects and advantages of the present
invention will be apparent from the following description,
reference being had to the accompanying drawings wherein pre-
ferred forms of the embodiments of the invention are clearly
shown.
Fig. 1 is a perspective view of a flasher apparatus
constructed in accordance with the present invention;
Fig. 2 is a top elevational view of the flasher
apparatus of Fig. l;
Fig. 3 is an end sectional view of the apparatus of
the preceeding figures~ with the section being taken along a
vertical plane through the center of the apparatus;
Fig. 4 is a top elevational view of a mounting
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~` strap comprising a portion of the apparatus of the preceeding -
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figures and;
Fig. S is a side elevational view corresponding to
Fig. 4
Referring in detail to the drawings, the flasher
of the present invention comprises a main housing indicated
generally at 20 which forms a cavity for receiving a circuit
board indicated at 70 in Fig. 3.
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The housing 20 is secured to the vehicle frame
by a mounting and grounding means or strap indicated generally
at 32 and shown in assembled relationship with housing 20 in
Fig. 1-3. Strap 32 includes flanges or shoulders 48 and 50
which form inner strap ground terminals, with such flanges
being bent from a central strap portion 46. One end of strap
32 includes external flanges 41, 43 and 37, with flange 37
including a mounting hole 39 for receiving a mounting screw
not illustrated. The other end of mounting strap 32 includes
external flange portions 40, 42 and 36 with flange 36 includ-
ing a second mounting hole 38. It will now be understood that
the exterior mounting flanges 36 and 37 form the external ground
connections for circuit board 70, since mounting strap 32 is
made from electrically conductive sheet metal material and
since the internal flanges 48 and 50 are plugged into circuit
board ground terminal 71 and 73 which extend upwardly from
circuit board 70, as seen in Fig. 3.
After the ground strap 32 is positioned on the
housing 20, as seen in Figs. 1-3 the cavity of the housing is
poured full of a suitable insulating compound 54 such as
epoxy resin, such that the compound surrounds the circuit board
and internal portions of mounting strap 32, including the
internal ground connections 50 and 71, and 48 and 73j thereby
securing the ground strap securely to the housing 20.
With continued reference to Figs. 1-3, a secondary
protective housing 44 is shaped from thin sheet metal 60 or
other suitable material, so as to provide a cavity for mounting
an electrical component, such as a switching relay, not illus-
trated, which relay is electrically connected to circuit board
70 via confronting openings in the two housing 20 and 44.
As seen in Figs. 1 and 3, secondary housing 44
includes side wall lower edges 51, which are extended into
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housing 20, so as to be positioned below the top of the poured
resinous material, whereby the resinous material mounts secon-
dary housing 94 on main housing 20 in sealed relationship
therewith.
With reference to Figs. l and, a plurality of
up-standing conductors 61, 62, 64 are electrically connected
to circuit board 70 at their lower ends, with each of the con-
nectors including a central shank embedded in the resinous
material and exposed upper ends that form a male plug that
removably connects with a female plug, not illustrated, whereby
external wires can be connected to circuit board 70.
While the form of embodiment of the present inven-
tion as herein disclosed constitutes a preferred form, it is
to be understood that other forms might be adopted.
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