Note: Descriptions are shown in the official language in which they were submitted.
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LOW PROFILE SIX-VOLT LEAD-ACID BATTERY WITH FRONT TERMINALS
FIELD OF THE INVENTION
This invention relates to six-volt lead-acid batteries and, more particularly,
to
a low profile six-volt lead-acid battery having front terminals.
BACKGROUND OF THE INVENTION
Lead-acid batteries have long been in use for a wide variety of applications.
For example, such cells and batteries have been used for what have sometimes
been
termed "stationary" battery applications wherein the lead-acid batteries
provide stand-
by power in the event of a power failure. For this type of application, such
stationary
batteries are maintained at a full-state-of charge and in a ready-to-use
condition,
typically by float maintenance charging at a constant preset voltage. By way
of
illustration, such stationary batteries may be used in telecommunications,
utilities and
the like.
In many applications, the space allotted for the battery is limited, yet there
is a
need for batteries having increased electrical capacity. For example, in some
stationary applications, the batteries are placed upon racks. Utilizing
batteries having
top terminals requires more battery space since clearance must be provided
above the
batteries so the installer can reach in above the batteries and make the
appropriate
electrical connections. Utilizing shelves that slide out may reduce some of
the
clearance required, but add additional cost for the rack structure required.
Further, as is known, current lead-acid battery designs create restrictions on
the height of the grids utilized. Thus, in general, and as is known, the grid
height that
may be utilized is limited by the requirements involved in sealing (typically,
heat
sealing) of the cover to the battery container and in providing appropriate
internal
electrical connections.
Thus, there is a need for a lead-acid battery having terminals located such
that
they can be accessed from the front of a battery rack or the like. Further,
there is a
need for such lead-acid batteries having enhanced electrical performance
without
requiring undesirably tall batteries, i.e., a low profile battery. Such
batteries,
however, must be capable of being assembled to provide a reliable battery
without
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requiring undue modification of conventionally used lead-acid battery assembly
processes and equipment.
Accordingly, it is a primary object of the invention to provide a battery that
may be efficiently utilized when placed in a battery rack without requiring
the use of
sliding shelves or excessive clearance above the battery. A related object of
this
invention is to provide a six-volt lead-acid battery having front terminals so
as to
facilitate access when such batteries are located in use in battery racks or
the like.
It is another object of the present invention to provide a low profile battery
having enhanced electrical performance.
A still further object lies in the provision of such low profile, front
terminal
batteries which are capable of being fabricated using existing lead-acid
battery
assembly techniques.
Other objects and advantages of the present invention can be seen from the
following description of the invention.
BRIEF SUMMARY OF THE INVENTION
The invention provides a low profile, 6-volt battery having both positive and
negative terminals disposed along the front of the battery, that is, having
both
terminals disposed along the front cell such that connections may be readily
made to
the terminals when the battery is disposed on a shelf. The battery container
is divided
by partitions into three cells disposed in a 1 by 3 arrangement with front,
middle, and
rear cells which each contain alternating positive and negative plates
separated by
separators. The lugs of the positive plates and the lugs of the negative
plates are
electrically connected by positive and negative straps, respectively, the
straps of
adjacent cells being electrically coupled by conventional means by through the
partition welds or the like.
In accordance with the invention, the elements of the front cell are
electrically
coupled to a front terminal along the front of the battery via a front cell
terminal
bushing, while the elements of the rear cell are electrically cozmected to the
front of
the battery, i.e., adjacent the front cell, by a connector bar. The lugs of
the rear cell
which are not coupled to the middle cell are electrically cormected by a strap
to an
upstanding post. The connector bar then couples the post to a front cell
terminal
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bushing which presents the terminal along the front of the battery. The
connection to
the post may be direct, or, alternately, a strap bushing may be welded to the
post and
the connector bar coupled to the strap bushing.
The terminals may be disposed along the front wall, along the top of the
battery substantially adjacent the front wall, along the sides of the battery
substantially adjacent the front wall, or as dual terminals substantially
adjacent the
front wall, i.e., as a combination of top terminals with side or front
terminals. In this
way the user may readily access the terminals even when the battery is
disposed on a
shelf which does not permit the user to reach in between.
Additionally, the battery may be readily constructed according to methods
known in the art. The invention provides a high quality, durable battery which
may
be economically and efficiently manufactured.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a perspective view of a preferred embodiment of a six-volt
battery according to teachings of the present invention.
FIG. 2 is a top view of a container used in the battery of the present
invention.
FIG. 3 is a cross-sectional view taken generally along line 3-3 of FIG. 2.
FIG. 4 is a cross-sectional view taken generally along line 4-4 of FIG. 2.
FIG. 5 is a plan view of an intermediate cover used in the battery of FIG. 1.
FIG. 6 is a cross-sectional view of the intermediate cover taken along line 6-
6
in FIG. ~ and illustrating one of the front cell terminals.
FIG. 7 is another cross-sectional view of the intermediate cover taken along
line 7-7 of FIG. 5 and showing the rear connection bushing and the other front
cell
terminal.
FIG. 8 is a bottom view of the intermediate cover of FIG. 5 and illustrating
the
respective positioning of the alignment guides for accommodation of a six-volt
battery as well as a twelve-volt battery.
FIG. 9 is a plan view of a final cover of a battery such as illustrated in
FIG. 1.
FIG. 10 is a bottom view of the final cover of FIG. 9.
FIG. 11 is an enlarged fragmentary view of the post and rear connector
bushing of FIG. 12.
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FIG. 12 is a top assembly view of the container and intermediate cover of FIG.
1 showing the cell elements, the intercell welds, and the connector.
FIG. 13 is a cross-sectional view of the assembly taken generally along line
13-13 of FIG. 12 and illustrating the internal electrical connections.
FIG. 14 is an end view of the assembly of FIG. 12 taken generally along line
14-14 in FIG. 12.
FIG. 15 is a connector arm of a first embodiment of the six-volt battery of
FIG. 1.
FIG. 16 is a cross-sectional view of the connector taken along line 16-16 in
FIG. 1 ~.
FIG. 17 is a cross-sectional view of the connector taken along line 17-17 in
FIG. 15.
FIG. 18 is a top assembly view of the battery assembly illustrating an
alternate
embodiment of the connector bar and the connection of the connector bar to the
internal components.
FIG. 19 is a top assembly view of the battery assembly illustrating a third
embodiment of the connector bar and the connection of the connector bar to the
internal components.
FIG. 20 is an enlarged fragmentary view of the post and connector bar of
FIGS. 18 and 19.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As is shown in FIGURE 1, the lead-acid battery 10 comprises a container 12
having side walls 14, a front wall 16, and a back wall 18. The composite cover
shown
generally at 20 comprises an intermediate cover shown generally at 22 sealed
or
otherwise attached to container 12, and a final cover 24 sealed to
intermediate cover
22. The battery 10, according to the preferred embodiment, includes a flame
arrestor
shown at 26, and positive and negative terminals 28, 30.
The container 12, as best seen in FIGS. 2-4, includes cross-partitions 34
dividing the container into three cells in a 1x3 cell configuration, with a
front cell 38,
a central cell 40, and a back cell 42. The terminal cells are thus defined by
the interior
surface of the side walls 14 (see FIG. 4), the front and rear walls 16, 18 and
by the
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surfaces of the cross-partitions 34. Although six-volt battery configuration
is
illustrated, the size of the cells can be varied as desired to satisfy the
space and
electrical performance requirements of the particular application.
An optional feature includes structure allowing the battery to be lifted,
5 whether by hand or other means. As is shown in FIG. 3, container 12 is
provided with
holes 46 located on front wall 16 and back wall 18 so as to accommodate a rope
or
other handle (not shown).
The illustrative embodiment utilizes a two-piece cover 20, that is, a cover
which includes an intermediate cover 22 and a final cover 24. As shown in
FIGS. 5-
8, the intermediate cover 22 is configured complementally with container 12 so
as to
allow the use of conventional heat sealing equipment to seal these components
together. In the preferred embodiment illustrated, the intermediate cover may
likewise be utilized in a 12-volt battery configuration having a 2x3 cell
arrangement
as opposed to the 1x3 cell arrangement illustrated in FIGS. 2-4. Accordingly,
the
1 ~ intermediate cover 22 includes a base structure shown generally at 50
divided by
intermediate cover center partitions 52 (see FIG. 8) configured to align with
center
partitions of a 12-volt container (not illustrated).
Access to the front cell 38 is provided by fill holes 54, while fill holes 56
and
~8 provide access to central cell 40 and back cell 42, respectively.
Optionally; and desirably, intermediate cover 22 likewise includes guide pins
70 (FIG. 8), preferably positioned both adjacent intermediate cover walls 68
and the
location of a central partition in a 12-volt battery so as to facilitate
assembly. Any
desired configuration of guide pins 70 can be used.
Additionally, the preferred embodiment of the intermediate cover 22 is
designed to provide common head space for the cells 38, 40, 42 and also to
allow for
pressure testing to ensure that appropriate sealing has been provided. As can
be seen
from FIGS. 5, 7 and 8, common head space is provided via fill holes 54. ~6, ~8
and
upstanding structure 78.
Inasmuch as the battery operates under pressure, the intermediate cover 22
also comprises valves 76, as may be seen in FIGS. 5, 7, and 8. In operation,
the
valves 76 operate to release pressure when a given pressure is exceeded within
the
battery 20.
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FIGS. 9-10 illustrate a preferred embodiment for the final cover 24. This
cover piece comprises a final cover base 82 complementally shaped so as to fit
upon
intermediate cover 22. Final cover 24 accordingly includes a front sealing
surface 84,
a rear cell sealing surface 86 and side surfaces 88 all complementally sized
with
respect to intermediate cover 22. Final cover 24 likewise includes structure
compatibly shaped and positioned with regard to fill holes 54, 56, 58 and
structure 78
of intermediate cover 22 so as to allow for the common head space. Appropriate
venting into such common head space can be achieved through venting techniques
known in the art. A flame arrestor 26 may likewise be included in the final
cover 24.
Turning back to the intermediate cover 22 and referring now to FIGS. 12 and
13, a battery is illustrated having the intermediate cover 22 and the cell
components in
place. Each of the three cells 38, 40, 42 contains a battery element
comprising a
series of alternately disposed positive plates (not visible) and negative
plates 100
having separators 102 positioned therebetween, as is known in the art (the
battery
element is illustrated only schematically in FIG. 12 to eliminate excess
lines). As
shown in FIG. 13, the negative plates 100 include upwardly extending lugs 104
which
are electrically connected together in each cell by a negative strap 106, 108.
The
positive plates of each cell similarly include lugs 110 which are electrically
connected
together in each cell by a positive strap 112, 114. The positive and negative
straps
112, 108 of adjacent cells may be electrically connected by conventional
intercell
connections. As shown in FIGS. 12 and 13, intercell welds 116 connect the
positive
and negative straps 112. 108 of adjacent cells 38 and 40, 40 and 42 via
conventional
tombstones 118.
The particular configuration and the number of plates and their respective
size
can be varied as desired for a particular application. Moreover, the present
invention
can be used whether the lead-acid battery is of the flooded electrolyte type
or sealed
type (i.e., a VRLA or valve-regulated lead-acid). Suitable grids and alloys
are known
and may be utilized, as are appropriate separator materials.
The intermediate cover 22 also houses the terminals 28, 30 and contains
structure allowing appropriate electrical connection to such terminals. As may
be
seen most clearly in FIGS. 6 and 12, a negative terminal bushing 120 having an
opening 122 is provided. The negative strap 76 of the front cell 38 is
connected to an
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upstanding post 124, which is received in the opening 122 in order to present
a
terminal 30 for connection. The bushing 120 and post 124 are coupled by any
appropriate method known in the art, e.g., welding, to provide an electrical
connection
to the negative terminal 30. In order to facilitate formation of the battery
12, the
bushing 120 further includes a formation adapter 126 to which a lead (not
shown)
may be coupled during formation.
It would be appreciated by those of skill in the art that a 1x3 cell
arrangement,
such as illustrated in the figures, would typically yield a terminal of a
first polarity at
one end of the container adjacent one cell, and a terminal of a second
polarity at the
opposite end of the container adjacent a cell disposed at the opposite end.
This is due
to the structural arrangement whereby a strap 106 of one polarity (in this
case, a
negative strap) is disposed adjacent one end of the battery 10 adjacent the
front cell
38, while a strap 114 of the opposite polarity (in this case, a positive
strap) is disposed
at the opposite end of the battery 10 adjacent the back cell 42.
In accordance with the invention, however, the positive and negative terminals
may both be disposed along the same end of the battery 10 adjacent a single
cell, in
this case the front cell 38. In this fashion, when placed upon a battery rack
or the like,
the positive and negative terminals 28 and 30 can be readily accessed, as is
needed in
service. In order to permit both terminals 28, 30 to be disposed adjacent a
single cell,
in this case, the front cell 38, the strap 106 of the front cell 38 is
connected to a
terminal 30 along the front cell 38 of the battery, while a connector or
metallic bar
130 is provided which electrically connects the strap 114 adjacent the back
cell 42 to
a terminal 28 substantially adjacent the front cell 38. While the respective
arrangement of the terminals 20, 30 will be described with respect to the
negative
strap 106 of the front cell 38 being connected directly to the front cell
negative
terminal 30, and the positive strap 114 of the back cell 42 being coupled to
the front
cell positive terminal 28 by way of the connector bar 130, the arrangement
might be
reversed such that a front positive strap is connected directly to a front
cell terminal
and a rear cell negative strap is coupled to the front of the battery by an
elongated
connector bar.
In accomplishing this objective, the positive strap 114 of the rear cell 42
comprises an upstanding post 132, similar to the negative post 124 of the
front cell 38.
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The post 132 is received in an opening 134 in a positive strap bushing 136 or
connector bushing as shown in FIGS. 11 and 13. As with the negative terminal
bushing 120, the positive strap bushing 136 includes a formation adapter 138
to which
a lead (not shown) may be coupled during battery formation. In contrast to the
negative terminal bushing 120, however, the positive strap bushing 136 does
not
include the positive terminal 28. In order to present a positive terminal 28
for
connection, a positive terminal bushing 140 is likewise provided along the
front cell
38. The positive terminal bushing 140 includes the positive terminal 28 which
is
presented at the front of the battery 12.
In order to couple the positive strap bushing 136 to the positive terminal
bushing 140, the bushings 136, 140 are each provided with upstanding coupling
structures 138, 142 in the form of hollow posts. The connector bar 130
comprises
openings 144, 146 at either end which may receive the posts 138, 142 to
electrically
connect the positive strap bushing 136 to the positive terminal bushing 140.
The
comlector bar 130 may be coupled to the posts 138, 142 by conventional
methods,
such as welding In this way, the rear cell 42 is directly connected to the
front terminal
28 such that both the positive and negative terminals 28, 30 are accessible
from the
front of the battery. As a result, when such batteries 12 are stored in a rack
(not
shown), the terminals 28, 30 may be easily accessed without necessitating that
the
shelves of the rack be movable even if the shelves are closely spaced.
It will be appreciated that the upstanding coupling structure 138 of the
positive
strap bushing 136 may likewise be utilized for the placement of a lead, or as
a
formation adapter, during formation of the battery 12. Utilization of the
formation
adapter 126 of the negative terminal bushing 120 and coupling structure 138 of
the
positive strap bushing 136 for attachment of the leads allows the manufacturer
to put
the acid into the cells 38, 40, 42 and clean the battery 12 prior to assembly
of the
connector bar 130 and welding it in place.
The connector bar 130 is preferably formed of copper to provide minimal
resistance. In the preferred embodiment illustrated in FIGS. 9 and 10, an
elongate
copper rod 150 is at least partially embedded in lead 152, and is offset from
attachment points or openings 144, 146 at either end. It will be appreciated
that the
battery 12 may be formed and cleaned as described above prior to assembling
the
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connector bar 130 to the battery, minimizing the opportunity for interaction
between
the acid and the copper of the bar 130. Further, in order to protect the bar
130, a final
cover 80 may be heat sealed to the intermediate cover 28, or a second cover
(not
shown) may be heat sealed to cover the compartment in the intermediate cover
22
containing the bar 130.
It will further be appreciated that the connector bar 130 may be alternately
laid
out and/or coupled between the strap 114 of the rear cell 42 and the terminal
28 of the
front cell 38. By way of example only, the connector bar 160 may be straight,
as
illustrated in FIG. 18, rather than offset. Further, the bar 160 may be
directly
connected to the positive strap post 168, as likewise illustrated in FIG. 18,
as well as
the embodiment illustrated in FIG. 19, FIG. 19 comprising a bar 170 which is
offset
as connected to the positive terminal bushing. In the embodiments shown in
FIGS. 18
and 19, a bushing 172 is molded into the intermediate cover 174 as shown in
FIG. 20.
An appropriate weld or the like is then made to electrically connect the post
168 to the
bushing 172, and the bushing 172 to the connector bar 160, 170. Alternately,
the
connector bar may be molded into the intermediate cover itself.
It should be appreciated that the particular configuration of the terminals
themselves can be varied as needed for the service requirements of the
particular
application. Internally threaded configurations, as are illustrated, are often
employed
in stationary applications where several batteries need to be electrically
connected
together. Further, while the embodiment shown has front terminals located
adjacent
the front wall 16 of the battery, it should be appreciated that top terminals,
either
alone or as dual terminals with the front terminals as illustrated might
alternately be
provided. Indeed, if desired, the terminals, either alone or as a dual
terminal
2~ configuration, could be located as side terminals adjacent the front of
side walls 14.
In any event, the terminals employed are located at least near the front wall
16 so as to
allow ready access in service.
It will likewise be appreciated that the connector bar arrangement would be
equally applicable to any cell arrangement comprising an odd number of cell
rows
extending rearward from the front wall of the battery. For example, the
connector bar
could be utilized in a 3x3 or 3x~ arrangement.
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Further, the manner and structure which is utilized to make the electrical
connections can vary as desired, consistent with the objectives of this
invention.
Thus, what is most important is that the terminals are accessible from the
front of the
battery and are located so as to minimize the profile of the battery.
