Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to a conductor bar assembly for
electrolytic cells for the recovery of metals and, more
particularly, relates to a conductor bar assembly for
conducting electrical current between electrolytic cells.
In electro-deposition processes for the recovery of
metals, direct electrical current is usually conducted through
ele~trolytic cells, each of which contains a multiplicity of
alternating cathodes and anodes. The electrodes are supported
from head bars in electrical contact with electrode contact
bars positioned on the side walls of the cells. The cells are
often arranged in groups which can be connected in series by
conductor bars, or bus bars.
Conventional conductor bars are made of an electri-
cally conductive material such as copper or aluminum and must
be of sufficient cross-sectional area to conduct the required
current. Because it is very desirable that the electrode
current is the same for each electrode in a cell, conductor
bars, ideally, must also provide an even current distribution.
Conductor bars used in the past have not been designed with
this requirement in mind and their use often resulted in uneven
current distribution. Moreover, conventional conductor bars,
which are usually of considerable dimensions to provide
sufficient current carrying capacity~ are usually
space-consuming.
We have now found that substantially even current
transfer from one group or row of cells to the next and,
consequently, substantially even current distribution from and
to electrodes in the end cells of the rows, can be attained by
a conductor bar assembly having a multiplicity of bus bars of
30 equal length which are connected between corresponding points
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over the lengths of two adjacent end cells and to the electrode
contact bars positioned on the end walls of the two end cells.
The provision of multiple paths of equal length between
corresponding points of the contact bars on the end cells thus
results in the same resistance and current for each path which
substantially eliminates uneven current distribution.
We have further found that equal paths can be
realized, while alleviating spac~ requirements, by connecting
the bus bars to each other in a generally V-shaped
configuration and by connecting the bus bars to the cells in an
overlapping fashion to form the conductor bar assembly.
To attain even current distribution, not only must the
length of each current path between corresponding points on the
respective contact bars be the same, but there must ideally be
a current path between each electrode in the one cell and its
corresponding electrode in the other cell. It is difficult,
however, to realize this ideal situation because of the number
of bus bars involved and the complexity of the resulting
assembly. For practical reasons, therefore, it is desirable to
connect a number of adjacent electrodes in the corresponding
position in a pair of cells via thèir respective contact barsO
The number of electrodes that can be connected is determined by
the requirement that essentially even current distribution
should be maintained.
Tb make it possible for a multiplicity of V-shaped bus
bars to fit in a fairly small space with a small
cross~sectional area, each V-shaped bar is preferably made up
of a number of laminated individual bus bar plates. These
laminated bus bar plates allow the weaving together of the
V-shaped bus bars into a conductor bar assembly, the use of
standard size metal bar stock for the bus bar plates, and
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facile construction and assembly. Laminated bus bars also
provide improved cooling of the assembly due to the larger
exposed surface areas and allow a total cross-sectional area of
the bus bar plates which is smaller than the cross-sectional
area of one-piece bus bars. Conversely, it is possible to
handle a greater amount of power for a given metal
cross-sectional area of the assembly. The number of
laminations, i.e. the number of bus bar plates making up a bus
bar, depends on the amount of current to be carried, the metal
cross-sectional area and, to a minor extent, on the size and
price of available metal bar stock.
Accordingly, there is provided a conductor bar
assembly for use in processes for the electro-deposition of
metals in which an electrical current passes through a
multiplicity of cells arranged in adjacent rows of cells, said
rows being connected in series by said conductor bar assembly,
said cells each containing a multiplicity of alternating
cathodes and anodes supported on electrode contact bars
positioned on the sides of the cells, said conductor bar
assembly comprising a first plurality of bus bars of equal
length extending laterally and downwardly externally from a
cell in a first row of cells towards an equal number of a
second plurality of bus bars o equal length extending
laterally and downwardly towards said first plurality of bus
bars externally from a cell in an adjacent row of cells, each
bus bar having an upper end and a lower end, the upper ends of
the first plurality of bus bars electri~ally connected to an
electrode contact bar on the side of a cell in the first row of
cells, along the length of said contact bar~ the upper ends of
~he second plurality of bus bars electrically connected to an
electrode contact bar on the side of a cell in the adjacent row
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of cells along the length o~ said contact bar, the lower end of
each bus bar of the first plurality of bus bars connected to
the lower end of a corresponding bus bar of the second
plurality of bus bars such that each pair of bus bars forms a
generally V-shaped configuration, whereby substantially even
current distribution is maintained along the lengths of the
electrically connected electrode contact bars to the anodes and
cathodes supported on said electrode contact bars.
According to one preferred embodiment, the conductor
bar assembly consists of a multiplicity of pairs of equal
length bus bars, each pair connected in a V-shaped
configuration.
~ ~ccording to another preferred embodiment, each
V-shaped configuration of bus bars is made up of a lamination
of bus bar plates.
PrPferred embodiments of the invention will now be
described with reference to the accompanying drawings, in which:
Figure 1 is an elevation of the conductor bar
assembly of the invention;
Figure 2 is a vertical section along line 2-2 of
Figure 1 of an upper portion of a bus bar
and an electrolytic cell showing connection
between a bus bar and an electrode contact
bar with electrodes seated thereon;
Figure 3 is a vertical section along the line 2-2 of
Figure 1, showing lamination of the bus bars;
Figure 4 is a perspective view of components
connecting a bus bar with a contact bar;
Figure 5 is a perspective view of an angle connection
plate;
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Figure 6 is a perspective view, partly cut away of
spacer plates with bus bar plates of
laminated bus bars;
Figure 7 is a front elevation of the inter-connection
of bus bars at their lower end in a V-shaped
configuration;
Figure 8 is a top view of the V-shaped configuration
shown in Figure 7 for laminated bus bars; and
Figure 9 is a perspective view of a conducting spacer
pla e as used in the connection shown in
Figures 7 and 8.
The conductor bar assembly of the preferred
embodiments is shown to comprise 16 bus bars, each connected to
a number of electrodes via an electrode contact bar and
connected in eight Y-shaped configurations of two bus bars
each. It is understood that the assembly can comprise more or
less than 16 bus bars connected in pairs in a V-shaped
configuration.
With reference to ~igures 1 and 2, cell 10 is the last
cell of a first row of cells 12 and cell 14 is the first cell
of a second row of cells lb. The designations "last" and
"first" are used to indicate that electrical current is
supplied from rectifiers to the first cell (not shown) in the
first row 12 of cells, passes through the electrically
connected cells to the last cell 10 of the first row 12,
crosses over from the first row to the first cell 14 of the
second row 16 of cells, passes through the electrically
connected cells of the second row and leaves the last cell (not
shown) of the second row to either cross over to a third row to
continue its flow or to complete the electrical circuit~
Electrode contact bars 18 are mounted on walls 22 of
adjoining cells in the rows to provide electrical contact for
essentially equispaced cathodes 24 and anodes 26 supported from
head bars 28, 30 in each cell. The electrode contact bars 18
can have a number of designs, such as typified by the electrode
contact bars disclosed in Canadian Patent 1 034 533 which
issued on 11 July, 1978. According to this patent, a contact
bar formed from electrically conductive metal is provided to
support the alternating equispaced anodes and cathodes
supported by their respective head bars. Each head bar 28, 30
has an end extension 32 at one end which is provided on its
underside with a notch 34 adapted to seat in a groove 36 formed
in a spooled central section 38 of the contact bar 18, shown
most clearly in Figures 2 and 4, the spooled central section 38
having a plurality of identical grooves 36 equally spaced alonq
the length of said spooled central section, the grooves 36 each
comprising a cylindrical middle portion 42 which is of
substantially smaller diameter than cylindrical end section 44
and is narrower than the wid~h of the notched end extensions 32
of the head bars 28, 30. The grooves 36 are shown to be formed
by bevelled portions 40, 41 facing one another on the opposite
sides of ~aid cylindrical middle portion 42 of each groove 360
In accordance with the present invention, the end
cells 10, 14 are each provided on their outer wall 20 with a
contact bar 18a similar to contact bar 18 but modified such
that it has a flattened underside 48 as shown in Figures 2, 3
and 4. Contact bars 18 are supported by insulators 50 more
fully described in applicants' assignee's co-pending Canadian
Patent Application 425,172 filed on April 5, 1983 and comprise
30 an elongated body formed of a synthetic material havinq
longitudinal outwardly and downwardly slopinq upper surfaces
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extending $rom a centre line to the side edges of the body and
a row of equi~spaced shoulclers formed longitudinally on each
upper surface adjacent to the said centre line offset relative
to each other, each row of shoulders having a transverse
channel formed between each pair of adjacent shoulders for
draining liquid towards a side edge of the body. A
longi~udinal V-shaped groove is formed between the two rows of
shoulders for supporting the spooled electrode contact bar
between the rows of shoulders and a cavity is formed in each
upper surface opposite each shoulder between the shoulder and
the respective edge of the body for receiving an insulating
block therein for supporting one end of the electrode head bars.
Contact bars 18a rest on contact bar connection plate
52 seated on smooth sloping surface 54 of modified insulator
50a (Figures 2, 3 and 4) outwardly inclined at a downward slope
of preferably about 3 degrees such that any accumulation of
liquid is prevented. Modified insulator 50a, supported on cell
wall 20 and by brackets 53, is similar to insulator 50 in that
it has sloping top surfaces, which slope away from its
longitudinal centre line to prsmote the drainage of liquid, but
it has only one set of shoulders 51, the other set having been
removed to accomodate modified contact bar 18a. The cavities
in insulator 50 may be retained or filled in for the modified
insulator 50a.
Plate 52 has a flat rectangular shape and is made of a
conductive metal such as copper. If desired, connection plate
52 can be made up of a number of sections. Contact bar
connection plate 52 extends the length of the contact bar 18a
on each cell wall 20 of cells 10 and 14. Contact bar 18a is
bolted with its flattened underside 48 on the top surface of
connection plate 52 at its upper side edge 56 abutting
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shoulders 51 of modified insulator 50a. Any gap betw~en bar
18a and plate 52 is filled with solder and further sealed with
an acid resistant putty. Contact bar connection pl~te 52 is
provided with bolt holes to receive bolts 58 for attachment of
angle connection plates 60, to be described.
The electrodes, comprising a multiplicity of
alternating cathodes 24 and anodes 26 each suspended from a
head bar, are supported on contact bars 18, 18a which extend
across substantially the length of side walls 20, 22 of cells
10, 14 as shown in Figure 2. Spaced along the length of and
attached to contact bar connection plate 52 are angle
connection plates 60. Each angle connection plate 60, shown in
detail in Figure 5, consists of an angle made of a conductive
metal such as copper and of sufficient cross section to carry
the desired amount of current. Each plate 60 comprises a
flange 62 and a flange 64, flange 62 defining an obtuse angle
of preferably about 93 with flange 64 such that when angle
connection plates 60 are attached to the sloping contact bar
connection plate 52 (slope preferably 3), flanges 64 are in
a substantially vertical plane. Flanges 62 and 64 are provided
with oblong slots 66 for adjustable attachment with bolts 58 to
contact bar connection plate 52 and bus bar attachment plate
70, respectively. Preferably, eight bolt slots are provided in
each of flanges S2, 64 to permit the use of eight connecting
bolts to provide good electrical contact and 11 evenly spaced
apart pla~es 60 are used for each of electrolytic cells 10, 14.
With reference to Figure 4, bus bar attachment plates
70 are elongated vertically positioned plates with rectangular
cross-sections, made of a conductive metal such as copper. The
bus bar attachment plates 70 are provided with holes 72 in the
upper portion 73, which correspond with slots 66 in flange 64.
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In this preferred embodiment, 11 sets of eight holes 72,
arranged in rectangular shaped patterns, are equispaced along
the upper portion of plate 70 to receive bolts 76. The
lower portion 78 of bus bar attachment plates 70 is provided
with holes to receive bolts 80 for attaching the bus bars 82 to
- be described In this preferred embodiment, eight sets of four
holes each, arranged in diamond-shaped patterns, are equispaced
along the lower portion 78. One plate 70 is located at cell 10
and one at cell 14~
10With reference to Figures 1, 2 and 7, bus bars
generally indicated at 82 are made of an electrically
conductive metal such as copper. Bus bars 82 can be of
substantially rectangular stock having an upper portion 84 and
a lower portion 86. Intermediate portion 88 of bus bars 82 is
preferably electrically insulated with an insulating material
such as, for example, a layer of fibre-reinforced plastic 90.
Upper portion 84 has an end surface 92 bevelled such that the
bevelled end of bus bar 82 is horizontal when the bus bar is
bolted to bus bar attachment plate 70. Roles are provided in
upper portion 84 to correspond with holes in the lower portion
78 of attachment plate 70, such that bus bars 82 can be bolted
thereto in the desired configuration for electrical
continuity. Lower portions 86 are bolted together in a
V-shaped connection as shown in Figure 7. The upper ends 84 of
the bus bars 82 are electrically connected to the electrode
contact bar~ 18a on outer walls 20 of cells 10 and 14 via
attachment plates 70, angle connection plates 60 and connection
plates 52. Preferably, the upper ends are electrically
connected substantially equidistant along the length of the
con~act barsa
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The number of pairs of bus bars 82 is determined by
the desired degree of evenness of current distribution along
contact bars 18a. It has been found that the use of eight
pairs of bus bars 82 attached to attachment plate 70 and
connected via eleven angle connection plates 60 and connection
plate 52 to contact bar 18a, gives essentially even current
distribution. The use of eight bus bars 82 for each cell also
provides a conductor bar assembly which requires relatively
little space. Each of the end cells 10 and 14 accommodates 51
anodes and 50 cathodes and each bus bar 82 i5, therefore,
indirectly connected with one-eighth of the electrodes in an
end cell, i~e., about six electrodesO
The eight bus bars 82 are attached to each of
attachment plates 70 on cells 10 and 14 such that the bevelled
end surfaces 92 are horizontal and the bus bars angle
downwardly in the direction of the other cell. The lower
portions 86 of corresponding bus bars from cells 10, 14 cross
each other in a V-shaped connection or common joint 96 and are
bolted together by bolts 98.
Common joints 96 form a sequence of horizontally
aligned joints extending from the first joint between the first
bus bar on cell 10 and the first bus bar on cell 14, i.e. to
the right as viewed in Figure 1, to the last joint between the
last bus bar on cell 10 and the last bus bar on cell 14, such
that each pair of bus bars 82 has a symmetrical V-shaped
configuration. The angle at which the bus bars are positioned
may vary and is generally determined by space requirementsO We
have found that an angle of about 30 from the horizontal is
preferred. It is understood that the other suitable angles may
30 be used.
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Bus bars 82 are further guided and supported by a
horizontal spacer 94 a~ cell 10 and a horizontal spacer 94a at
cell 14. Spacers 94 and 94a, generally indicated in Figures 1
and 2, which are similar to spacers 106, 108, 110 and 112 which
will be described hereinbelow with references to Figures 3 and
6, consist of a bar with generally rectangular cross-~ection
made of an insulating material such as fibre-reinforced
polyester or high density polyethylene. Spacers 94 and 94a
have a number of equispaced9 diagonal grooves, not shown, of a
width and depth equal the width and thickness of a bus bar 82.
The number of grooves in each spacer 94, ~4a corresponds to the
number of bus bars 82 attached to each of the cells 10 and 14,
i.e. eight grooves according to this preferred embodiment. The
angle of each groove to the horizontal is the same as the angle
with which bus bars 82 slope downwardly from the cells. Spacer
94 is fitted behind the bus bars 82 attached to cell 10, as
shown in Figure 2, and spacer 94a is fitted in front of the bus
bars 82 attached to cell 14. This fitting laterally off-sets
the set of bus bars attached to cell 10 from that attached to
cell 14 allowing intermediate portions 88 of each set to cross
without physical contact until at the lower portions where the
bus bars are joined to form common joints 96. It is understood
that other means of off-setting the bus bars can be used.
Preferably, each bus bar 82 is laminated to form
laminated bus bars 82a. A laminated bus bar 82a consists of at
least two spaced-apart bus bar plates. With reference now to
Figure 3, 4, 6 and 8, each laminated bus bar 82a is made of a
lamination of spaced-apart bus bar plates 100. Preferably four
spaced-apart bus bar plates 100 are used but a lesser or
greater number can be used equally well~ The cross-sectional
area of laminated bus bars 82a is about the same as but usually
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less than that of rectangular bus bars 82 with equal current-
carrying capability and should be sufficient to carry the
desired amount of current. The bus bar plates 100 are of
uniform rectangular shape with bevelled ends; the upper ends
bent inwardly at 102, Figures 3 and 4, for securement in pairs
to each side of attachment plates 70, as shown for the
embodiment illustrated in Figures 1 and 3.
In order to form a spaced apart lamination, the four
bus bar plates 100 of a bus bar 82a have lateral off-sets 102a,
102b, 102c and 102d at their upper ends, shown most clearly in
Figures 3 and 4, formed symmetrically about the bus bar
longitudinal centre line 101. Bus bar plates 100 are separated
by spacers similar to horizontal spacers 94, 94a. Inner plates
lOOb and lOOc are separated by a horizontal spacer 106, shown
in Figures 3 and 6, and outer plates lOOa and lOOd are
separated from inner plates lOOb and lOOc by horizontal spacers
108 and 110. Each of spacers 106, 108 and 110, together with
rear spacer 112, consists of a bar with a generally rectangular
cross-section made of an insulating material, such as
fibre-reinforced plastic or high density polyethylene. Each
spacer 106, 108, 110 and 112 has a number of equispaced
parallel, diagonal grooves 114 of a width and depth equal to
the width and thickness of a bus bar plate 100. The number of
grooves 114 corresponds to the number of bus bars 82a attached
to ~ither cell 10 or 14, i.e., in this preferred embodiment
there are eight grooves. The angle to the horizontal of each
groove is the same as the angle with which bus bars 82a or bus
bar plates 100 slope downwardly from the cells, i.e. 30 from
the horizontal.
With reference to Figures 2 and 3, each set of bus
bars 82 or 82a from cell 10 and cell 14 has horizontal spacers
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94, 94a and spacers 106, 108, 110 and 112, respectively,
clamped together by means of bolts 118 extending between two
vertical support plates 120, 122 through holes 123 in the
horizontal spacers. Vertical support plates 120, 122 are
welded perpendicularly to horizontal support plates 123, 126
respectively for securement onto concrete piers 128 with lag
bolts 130. Concrete piers 128 are provided at cells 10 and 14
on both sides of the conductor bar assembly. ~orizontal
support plates 124, 126 extend over and straddle piers 128 at
both cells 10 and 14. An insulator 132 is provided between
concrete piers 128 and the horizontal support plates 124, 126.
With reference now to Figures 1, 3, 7, 8 and 9, the
lower portions 86 of each bus bar 82 and of bus bar plates 100
of bus bars 82a are joined in fixed relationship in a rigid
V-shaped configuration at common join~ 96. In common joints
96, each bus bar 82 from cell 10 is separated from the
corresponding bus bar 82 from cell 14 with a V-connection
conducting spacer plate 140 interposed therebetween to provide
the required off-sets. Similarly, each bus bar plate lOOa
lOOb, lOOc and lOOd of bus bar 82a is separated from its
adjacent plate with a V-connection conducting spacer plate 140
interposed there- between. V-connection conducting spacer
plate 140 is a rectangularly-shaped plate made of an
electrically conductive metal such as copper. Holes 142 are
provided which correspond with holes formed in bus bars 82 or
the bus bar plates 100 for securement together by bolts 98.
The four bus bar plates lOOa, lOOb, lOOc and lOOd comprising
each bus bar 82a from cell 10 are interwoven in partly
overlapping fashion with the four corresponding bus bar plates
30 from cell 14 with the V-connection conducting spacer plate 140
between adjacent bus bar plates. The bus bar plates and
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conducting spacer plates are joined in fixed relation with
bolts 98 to form the rigid V-shaped connection or common joint
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Bolts, nuts and washers used to connect the various
metal parts to form the conductor bar assembly are made of a
conductive metal. When using copper as material for the metal
parts of the assembly, it is preferred to use silicon bronze
bolts, nuts and washers.
It is understood that modifications can be made in the
embodiment of the invention illustrated and described herein
without departing from the scope and purview of the invention
as defined by the appended claims.
14.
