Battery compartment cap having an improved contact

Details Battery compartment cap having an improved contact Battery compartment cap having an improved contact

1995-10-20

2001-02-27

Chaney, Carol (Department: 1745)

Chemistry: electrical current producing apparatus, product, and

Adjuncts in combination with or for connection to an...

C429S123000

Reexamination Certificate

active

06194097

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates generally to battery compartment caps and more specifically to a removable battery compartment cap having a one piece contact assembly.
BACKGROUND OF THE INVENTION
Battery compartments for housing batteries used in powering various electronic devices such as night vision goggles, flash lights, camera light meters, etc., are well known in the art. Such battery compartment designs include removable battery compartment caps which enable the battery or batteries contained within the compartment to be removed and replaced with a new or recharged battery or batteries.
Referring to
FIG. 1A
, there is shown a AN/PVS-7B night vision goggle device
58
(illustrated by the dotted lines) which includes a horizontally oriented PVS-7B battery compartment
50
closed by a removable prior art PVS-7B battery compartment cap
10
. The battery compartment cap is tethered to the night vision goggle device by a retainer strap
57
. As can be seen in
FIG. 1C
, the battery compartment
50
is loaded with either Lithium Sulfur Dioxide BA-5567/u batteries
52
(only one is shown) or two (2) AA batteries.
FIG. 1B
is an exploded perspective view of the removable battery compartment cap
10
of FIG.
1
A. As shown, the battery compartment cap
10
generally comprises a cap member
12
, the retainer strap
57
, a retainer link
59
, an o-ring
48
and a contact assembly
28
. The cap member
12
includes a circular top
14
and an annular skirt
24
depending from the periphery of the circular top
14
. The compartment side surface of the circular top
14
includes a centrally disposed contact locating post
16
surrounded by an annular contact seating flange
18
and a circumferential lip
20
. The circumferential lip
20
in conjunction with the annular skirt
24
define a groove
22
for receiving the o-ring
48
that seals the battery compartment cap
10
to the battery compartment
50
. The exterior surface of the circular top
14
defines a centrally disposed projection
15
with an enlarged end
17
for coupling the battery compartment cap
10
to the retaining strap
57
. The retaining strap
57
is coupled to the night vision goggle device
58
by a retainer link
59
. A thread arrangement
26
for securing the battery compartment cap
10
to the battery compartment
50
is provided on the inner surface of the annular skirt
24
.
Still referring to
FIG. 1B
, the contact assembly
28
includes a stamped metal contact
30
, a washer
38
, a circular retaining clip
40
and a conical-shaped coil spring
42
. The contact includes a hub
32
portion with a centrally disposed aperture
33
. Three spoke members
34
extend radially from the periphery of the hub portion
32
. In between any two of the three spoke members is a tab
36
. Each tab
36
extends axially in the direction of the spring
42
from the periphery of the hub portion
32
. The circular retaining clip
40
that retains the contact
30
to the contact locating post
16
includes sharp projections
41
which cut into the locating post
16
. The coil spring
42
includes a large diameter end
44
and a small diameter end
46
.
Each component of the contact assembly
28
must be separately assembled to the cap member
12
as follows. First, the contact
30
of the contact assembly
28
is assembled to the cap member
12
so that the hub
32
portion engages the annular seating flange
18
while the contact locating post
16
extends through the aperture
33
of the hub portion
32
. Next, the washer
24
is installed onto the contact locating post
16
so that it rests against the hub portion
32
of the contact
30
. The retaining clip
40
is then press-fitted to the contact locating post
16
. Additional retention is sometimes provided by heat staking the free end of the contact locating post
16
after the retaining clip
40
is press fitted thereto. Finally, the coil spring
42
is non-removably secured to the contact
30
by the three tabs
36
. This is accomplished by bending each tab
36
around a portion of the first coil of the large diameter end
44
of the coil spring
42
to mechanically secure the coil spring
42
to the contact
30
. Then, each tab
36
is soldered to the coil to ensure electrical continuity between the coil spring
42
and the contact
30
.
A completed electrical circuit is provided when the battery compartment cap
10
is installed on the battery compartment
50
loaded with batteries
52
as shown in FIG.
1
C. The electrical circuit is created by the mechanical and electrical contact between the small diameter portion
46
of the coil spring and the negative end of the battery
52
, and the solder connections between the coil spring
42
and the contact
30
. The circuit is completed by the physical touching of the contact
30
to a ground sleeve
54
in the battery compartment
50
.
Although the battery compartment cap
10
of
FIGS. 1A-1C
operates in a generally satisfactory manner, there exists certain disadvantages which reduces its utility. One disadvantage is that the contact assembly
28
is comprised of four (4) separate components which must be assembled in a process which involves three bending operations and three soldering operations which add complexity to the manufacturing of the battery compartment cap
10
. Another problem with the battery compartment cap
10
is that it presents difficulties when the batteries
52
are changed. More particularly, when the battery compartment cap
10
is applied to the battery compartment, the relatively long free length of the uncompressed coil spring
42
(represented in
FIG. 1C
as dotted lines) causes it to contact the battery
52
before the thread
26
of the battery compartment cap
10
engages the thread
56
of the battery compartment
50
, thereby requiring a significant compression force to apply the battery compartment cap
10
. This causes difficulty when changing batteries, especially under adverse circumstances. Still another problem with the above design concerns the possibility of missed contact when loading certain types of batteries. In particular, certain types of batteries have diameters which are significantly small than the diameter of the battery compartment. If such batteries are loaded into the battery compartment when the battery compartment is oriented horizontally, the batteries tend to sit in an off-centered manner within the battery compartment. Consequently, when the battery compartment cap is applied to the battery compartment the small diameter end of the spring may not contact the batteries.
It is, therefore, a primary object of the present invention to provide an improved battery compartment cap with a one-piece contact assembly that substantially overcomes the disadvantages associated with prior art battery compartment caps.
SUMMARY OF THE INVENTION
A removable cap for closing an associated battery compartment housing at least one battery. The cap comprises a cap member and contact means attached to the cap member for completing an electrical circuit with the at least one battery housed within the battery compartment. The contact means includes a unitarily formed sliding biasing member for making mechanical and electrical contact with the at least one battery.


REFERENCES:
patent: 1215757 (1917-02-01), White
patent: 1286800 (1918-12-01), Schulte
patent: 5108847 (1992-04-01), Edwards et al.
patent: 5186665 (1993-02-01), Kelly et al.

Affiliated with

Also associated with

Rating

Battery compartment cap having an improved contact does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Battery compartment cap having an improved contact, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Battery compartment cap having an improved contact will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2599691