Note: Descriptions are shown in the official language in which they were submitted.
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1 ~ This invention relates to improvements in cathode base
2 plates for use in the electrolytic refining of metals and to
3 apparatus for peeling electrodeposited metal plate from the
4 cathode base plate.
According to conventional electrolytic refining techniques,
6 nonferrous metals are refined by electrodepositing the nonferrous
7 metal onto a cathode base plate (which will be referred to as
8 "base plate" hereinafter) installed within an ele~trolytic cell.
9 A cathode plate with electrodeposited metal (which wili be
referred to as "cathode plate" hereinafter) formed thereon as
11 electrodeposi~ed metal plate (which will be referred to as ~metal
12 platen), is then stripped by inserting a stripping means such as
13 wedge scraper, knife or the like between the base plate and the
14 metal plate constituting the cathode plate.
~s will hereinafter be explained more fully, problems exist
16 with conventional base plate structures, in that the stripping
17 means does not reliably engage the junction between the cathode
18 plate and the metal plate to begin stripping the lattar away from
19 the cathode plate~ Although attempts have been made to better
d fine this junction and enable more positive engagement by the
21 stripping means, the base plate structures have proven to be more
22 susceptible to damage. Other problems which have been
23 encountered by the prior art arrangements have been damage to the
24 cathode plate and for metal plate by the force of the cla~ping
means used to hold the assembly during the stripping operation
26 and the necessity for relatively complicated and expensive drive
27 mechanisms for the stripping means.
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1 According to the present invention, there is provided a
2 cathode base plate or use in electrolytic refining in which a
3 metal is electrodeposited on said base plate and subsequently
4 peeled therefrom. The base plate has an edge portion of reduced
S thickness compared with at least the adjacent regions of said
6 plate, said portion having a pluraLity of openings therethrough.
7 An insulating material is mounted on and embraces said edge
3 portion with the outer surfaces of the insulating material
9 es~entially flush with the adjacent surface regions of-said plate
with said insula~ing material extending through said openings to
11 lock said insulating material to said base plate. Preferably,
12 the insulating material is either located in one corner of the
13 base plate or centrally of one edge thereof.
l4 In a further aspect of ~he invention, there is provided
apparatus for ~tripping cathode base plates in electrolytic
16 refining comprising:
17 a supporting means for holding a cathode plate with electro-
18 deposited metal in an upright position;
19 a pair of stripping members each having a wedge-shaped strip-
ping el~nent mounted thereon with said ele~ents in opposed
21 relationship with one another;
22 resilient ~eans ~ctlng ~ said ~r~ng m~rs to ~rge s~id.strlpping
23 elements either t~s or away from one another;
24 means for moving said stripping members to cause said wedge-
shaped elements to travel downwardly across the opposed surfaces
26 of said plate; and
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1 wedge-spacing control means crr~peratLng with said stripping nEI~bers
2 and ~ ng said ~eY}~r-~h~pel elements towards or away from one another
3 ~ t the bias of said resilient means such that said elements are bia~ed
4 towards one a~other and respectively engage ~he opposed surfaces of said
plate for a brief initial peri~d of travel of s3id elements acr3ss Saia
6 surfaoes and thex~ ber are biased away from one another.during the rem2inder
7 of their t~nel acrDsS said ~faces to maintain a ~ing be~n said
8 ~ ~ a~d tbe res~ive e~Ents.
~ Pr~r~bly~ th~ ~a~hode ~as~ plate ha~ a ~upport bea~
secured thereto and suspended at both ends from a bracket forming
11 part of said supporting mean~. The supporting means preferably
12 includes a chain conveyor upon whirh said cathode base plate
13 rests and guide bars between which said base plate is moved by
14 said chaLn conveyor. Preferably, the stripping members are
arranged to ~ove said wedge-shaped stripping elements along a
16 circular arc from one upper corner of said pLate to the
17 diasonally opposite lower corner of the cathode base plate or
18 vertically downwardly in a plane containing the cen~re line of
19 said cathode base plate, from the upper part of the cathode base
plate to the lower part thereof~ Each said stripping m~mber is
21 preferably formed from springy material and is of varying
22 thickness to present an outer surface of varying contour which
23 e~gages with a fixed member during travel of said stripping
24 members to cam the stripping members and the asscciated stripping
elements away from ~nd towards one another, the fixed member
26 preferably comprising a cam means having a pair of cam plates
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1 respectively disposed outwardly of said stripping members, and
2 each cam plate being provided contoured inwardly facing surfaces
3 of said stripping members. In another preferred embodiment of
4 the invention, the wedge-spacing control means comprises a cam
S means having a cam member disposed between stripping members,
6 said cam means having opposed outwardly facing surfaces adap~ted
7 to contact inwardly facing surfaces of said-stripping members,
8 and means having regions of increased thickness at each end and
9 an intermediate region of decreased thickness, whereby said
stripping members and the associated wedge-shaped stripping
11 ~lements stripping members pass said regions of increased
12 thickness and move towards one another as said stripping members
13 pass said regions of decreased thickness.
14 The invention will now be described further by way of
example only and with reference to the accompanying drawings,
16 wherein-
17 Fig. 1 illustrates two examples of prior art base plates
18 wherein Fig. l(a) is a vertical sectional view of the upper part
19 of one said example and Fig. l(b) is a transverse sectional view
of one side of the other said example;
21 Fig. 2 is a view illustrating one preferred embodiment of
22 the base plate according to this invention wherein Fig. 2(a) is a
23 front view of the base plate as a whole and Fig. 2tb) is a
24 sectional view taken on line II-II of Fig. 2(a);
Fig. 3 is a view illustrating another preferred embodiment
26 of a base plate according to this invention wherein FigO 3(a~ is
l a front view of the base plate as the whole and Fig. 3(b) is a
2 sectional view taken on line III-I~I of Fig. 3~a);
3 Fig. 4 is a front view, illustrating the stripping operation
4 being performed on the base plate of Fig. 2 by use of stripping
apparatus embodying this invention;
6 Fig. 5 is a plan view taken on line V-V of Fig. 4;
7 Figs. 6 to 9 are partly enlarged plan v-iews illustrating the
8 positiona7 relationship between the base plate and the stripping
9 means in the practice of the stripping operation shown in FigO 4;
Fig. 10 is a partly broken plan view illustrating the
ll ~tripping operation ~eing performed on the base plate of Fig. 2
12 in accordance with another embodiment of the stripping apparatus
13 according to this invention;
14 Figs. 11 to 14 are partly enlarged plan views illustrating
the positional relation between the base plate and the stripping
16 means in the practice of the stripping operation shown in Fig~
17 lO;
18 Fig. 15 is a plan view illustrating the stripping operation
l9 being performea on the base plate of Fig. 3 in accordance with
yet another embodiment of the stripping apparatus according to
21 this invention~
22 Figs. 16 to l9 are partly enlarged plan views illustrating
23 the positional relation between the base plate and the stripping
24 means in the practice of the stripping operation shown in Fig.
lS; and
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1 Figs. 20 and 21 are partial plan views illustrating two
2 further embodiments of the base plate according to this
3 invention.
4 Fig. l(a) and tb) are upper and side sectional views
illustrating two examples of prior art cathode plate embodiments,
6 which are respecti~ely labelled A' and A". In the case of such
7 cathode plates as ~' and ~'q, automatic stripping apparatus is
8 commonly employed for the purpose of peeling off the metal plate
9 2' or 2" rom the base plate 1' or 1" respectively.
Referring to the cathode plate ~ of FigO l(a), firstly, the
11 stripping operation is effected by mechanical or fluid impact
12 against the upper end of the metal plate ~' by means of a hammer
13 or air jet, thereby forming fine voids in th~ junction 5' between
14 the base plate 1' and the metal plate 2' along the upper edge of
the latterO The stripping means (not shown) is then inserted
16 downwardly against the junction to strip the plate 2' from the
17 base 1'. However, the chamfered upper edge of the plate 2'
18 hinders insertion of the stripping means, which tends to ride
13 over the plate iastead of wedging itself in the junction 5'.
Next referring to Fig. ltb), the cathode plate 2" is
21 obtained by the steps of forming a narrow tongue 6" along a part
22 of the side edge of the base plate 1", mounting a channel-shaped
23 insulating material 4" thereon so as to cover both sides of the
24 tongue, the thickness of said insulating material being identical
to or thinner than that of the base plate 1", and
26 electrodepositing the metal plate 2". In this case, the
27 stripping operation is again carried out in the manner of forming
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1 fine voids in the junction 5" between both plates 1" and 2",
2 inserting the stripping means thereinto and moving said stripping
3 means toward the left in the drawing and then vertically~ The
4 cathode plate illustrated in Fig. l(b), whose junction is more
distinct than that of Fig. l(a~, facilitates insertion of the
6 stripping means, but a problem arises in that the insulating
7 material 4" is liable to fall off the base plate 1" due to
8 impacts caused during the transportation of the base plate 1",
9 corrosion by electrolyte and the like. If this happens, the
insertion of the stripping means is made still more difficult and
11 so it is necessary to mount a new piece of insulating material 4"
12 on the tongue 6 n SO that the stripping operation may proceed.
13 Referring to the examples of both Figs. l(a) and l(b), the
14 base plate is likely to be damaged by impact at the time of
forming fine voids between it and the metal plate, by the force
16 exerted by clamping means whicb are used to hold the base plate
17 during the stripping operation and so forth. ~dditionally,
18 damage may be caused by the stripping means pressing against the
19 base plate during the stripping operation.
A further problem with such known apparatus is that since
21 the stripping means is designed to make a rectilinear motion and
22 so has a lonsi stroke, a fluid cylinder is normally used to
23 provide this movement. In order to avoid the use of a long
24 cylinder it is necessary to increase the stroke by means of a
rack pinion or the like. Such apparatus is generally large and
26 complicated.
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1 Fig. ~ and Fig. 3 illustrate alternative embodiment~ of base
2 plates according to this invention, wherein reference numeral 1
3 denotes a base plate in both figures. Fig. 2 illustrates the
4 base plate 1 provided with an insulating material 4 located in
the upper part of its right hand edge, and Fig. 3 illustrates the
6 base plate provided with an insulating material 4 located
7 centrally of its upper edgeO
8 The insulating material 4, as seen from the view in line
9 II-II of Fig. 2(a) and the enlarged sectional view along the line
III-III of Fig. 3(a), respectively, comprises a plastic material
11 such as epoxy or polyester resin and the like or rubber, and is
12 partly embedded in holes ~ perforated in the thinned tongue
13 portion of the base plate which may for example he 2 mm thick in
14 a plate having an ordinary thickness of 6mm. Both sides of the
insulating material 4 are thus connected through the thin tongued
16 portion of the base plate 1, the total thickness of the
17 insulating material 4 being substantially identical with that of
18 the base plate 1. In this context, it is to be noted that
19 reference numeral 6 denotes a conventional insulating frame for
separating adjacent metal plates from one another.
21 In the thus constructed base plate 1, wherein the insulating
22 material 4 is attached onto both sides of the base plate 1 and
23 secured by the portions embedded in through holes 5, there is no
24 possibility of the insulating material 4 falling away from the
base plate 1 even when impact is applied to the base plate 1 or
26 the base plate 1 is attacked by corrosion.
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1 When the base plate 1 thus constructed is employed, the
2 peripheral edge portion 3 of the metal plate 2 formed upon
3 electrolytic refining will not deposit on the insulating material
4 4 and effectively forms a wedge-like gap C suitable for inserting
wedges or other peeling means, as shown in Fig. 2tb).
6 Referring now to Figs. 4 to 9, apparatus for removing the
7 plate 2 in Fig. 2 comprises a supporting bracket 27 and a
8 stripping apparatus generally designated 15. A cathode plate ~,
9 in which a base plate 1 is coated on both sides with a metal
plate 2, is arranged with a number of similar plates into a set
11 of about ten such plates by means of a hoist or the like and
12 suspended from a beam (not shown) at regular intervals within a
13 bracket 27.
14 The stripping apparatus 15 is aligned with the cathode plate
1, and includes a pair of stripping members 8 and 8' located on
16 either side of the base plate 1, a cylinder 19 operating said
17 members 8 and 8', and a cam plate 7 dafining the spacing between
18 members 8 and 8'. Stripping members 8 and 8' are pivotally
1.9 supported at their lower ends on a brac~et 9 secured to the
bracket 27 by means of a pin 14, and wedges 10 and 10' are
21 mounted on the upper ends of the members 8 and 8'. The members 8
22 and 8', being formed from a flat spring, are normally parallel,
23 and are so designed that wedges 10 and 10' are urged together
24 when no external force is applied. The cylinder 19 is pi~otally
supported by means of a pin 12 on a bracket 11, the latter being
26 mounted on the bracket 27, and the head 13 of a piston rod i5
;27 pivotally s~lpported in the base plate o members 8 and 8' by the
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1 aid of a pin 14. The cam plate 7, which i5 attached at its base
2 end to the bracket 27, is located midway between members 8 and 8'
3 above the cylinder 19 and includes ront and rear portions of
4 increased thickness 16, 16' and 17, 17' and middle portions 18,
18' oE decreased thickness.
6 rhe stripping operation using the aforesaid appartus will be
7 explained hereinafter mainly with reference to Figs. 6 to 9. The
8 stripping members 8 and 8' are shown in the various positions
9 designated by the symbols VI-IX in Fig. 4, are further
illustrated in Figs. 6 to 9, wherein Figs. 6~a~ through 9(a3
ll illustrate the relative positions between wedges 10, lO' and the
12 base plate 1 and Figs. 6(b) through 9tb~ illustrate the relative
13 positions between members 8, 8' and the respective parts of the
14 cam plate 7, respectively.
~t the time when the base plate 1 has been supported at the
16 predetermined position of the bracket 27 as shown in Fig. 4, the
17 members 8 and 8' are positioned at VI, wherein the members 8 ~nd
lB 8', as shown in Fig. 6~), are spaced from each other by the
l9 thicker portion tl7, 17') of the cam plate 7 so that the spacing
between wedges 10 and 10' is greater than the thickness of the
21 base plate 1. The me~bers 8 and 8' are remote from the
22 insulating material 4 at this stage.
23 The cylinder 19 is then actuated to move members 8 and 8'
24 towards the insulating material 4 and when the members reach the
position VII in Fig. 4, they move to the thinner part (l8,18') of
26 the cam plate 7 as shown in Fig. 7(b) and are urged together by
27 their natural resilient force so that w~dges 10 and 10' are urged
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1 into contact with both sides o the insulating material 4 of the
2 base plate 1 as shown in Fig. 7(a~.
3 When members 8 and 8' reach the position VIII in Fig. 4,
4 wedges 10 and 10', as shwon in Fig. 8(a), enter the junction gap
C (Fig. 3(b)) between the metal plate 2 and the base plate 1 the
6 stripping operation of the metal plate 2 from the base plate 1
7 thus begins and continues while members 8 and 8' move along the
8 lower thin portion (18,18') of the cam plate 7 as shown in Fig.
9 8(b).
When the stripping operation is carried out by wedges 10 and
11 LO 7 in the aforesaid manner and members 8 and 8' reach
12 substantially the position IX in Fig. 4, members 8 and 8' engage
13 the thicker portion (16,16') of the cam plate 7 as shown in Fig.
14 9(b) and consequently are forced apart again, whereby wedges 10
and 10' are moved away from both sides of the base plate 1. The
lÇ final stripping operation is carried out in this position. Whil~
17 th~ aforesaid stripping opera~ion is in progress, wedges 10 and
18 10' move in an arc about the pin 14' as its center, as indicated
19 by the arrow and when the wedges arrive at the position X in Fig.
~0 4 the stripping operation is completed.
21 In the embodiment of Figs. 10 through 14 t the members B and
22 8' are made of spring strip and are biased by their natural
23 resilience away from each other. Consequently, if there is no
24 external obstacle present, the wedges 10 and 10' will be spaced
from the base plate 1.
26 Cam plates 7 and 7' are located outside of the members 8 ana
27 8' and mounted on the bracket 27. Said cam plates are pr~vided
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1 at their forward ends with higher profile portions 16 and 16' and
2 at their rear ends with lower profile portions 18 and 18', as
3 shown in Figs. 11 to 14.
4 In Figs. 11 to 14, Figs. ll(a~ through 14(a~ indicate the
relative positions between wedges 10, 10' and the base plate 1
6 and Figs. llta) through 14(a) illustrate the relative positions
7 between members 8, 8' and the respective parts of cam plates 7,
8 7l, the members 8 and 8' being shown in various positions XI to
9 XIV of Fig. 10.
~t the time when the base plate 1 has been supported at the
11 predetermined position of the bracket 27 as shown in Fig. 10,
12 members 8 and 8l are positioned at XI, wherein scrapers 8 and 8',
13 as shown in Fig. lltb), are spaced from each other so that the
14 higher portions 23 and 23' thereof face the lower portions 18 and
18' of the cam pla~es 7 and 7' and the spacing between wedges 10
16 and 10' is greater than the thickness of the base plate 1, the
17 wedges being remote from the insulating material 4.
18 The cylinder 19 is then actuated to move membPrs a and 8'
19 and when they reach the position XII in Fig. 10~ the higher
portions 23 and 23' of members 8 and 8' move toward the higher
21 portions 16 and 16' of cam plates 7 and 7' as shown in Fig. 12(b)
22 and are forced towards one another against their natural spring
23 forces so that wedges 10 and 10', contact both sides of the
24 insulating material 4 of the base plate 1 as shown in Fig. 12(a)
and slide along these sides toward the metal plate 2.
26 When members 8 and 8' arrive at the position XIII in Fig.
27 10, wedges 10 and 10', as shown in Fig. 13~a), enter the junction
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1 gap between the metal plate 2 and the base plate 1~ The peeling
2 operation of the metal plate 2 from the base plate 1 thus begins
3 and this state continues while the higher portions 23 and 23' o
4 wedges 8 and 8' move along the higher portions 16 and 16' of cam
plates 7 and 7' as shown in Fig. 13(b).
6 When the stripping operation is performed by wedges 10 and
7 lO' as described and members 8 and 8' reach substantially the
8 position XIV in Fig. 10, the higher portions 23 and 23' of
9 scrapers 8 and 8' disengage the higher portions of cam plates 7
and 7' as shown in Fig. 14(b) and consequently move away from
11 each other again, whereby wedges 10 and 10~ are urged away from
12 the respective sides of the base plate 1. The final stage of the
13 stripping operation is carried in this condition.
14 While the aforesaid stripping operation is in progress,
wedges lO and 10' move along an arc with the pin 14' as the
16 center. When the wedges arrive at the position XV in Fig. 10 the
17 stripping operation is completed.
18 A third embodiment is illustrated in Figs. 15 to 19,
l9 respectively and is particularly adapted to the structure of FigO
3.
21 The stripping apparatus illustrated in Fig. 15 includes a
22 chain conveyer 29 carrying thereon the lower end of the base
23 plate 1, a supporting means comprising guide bars 30 located on
24 both sides of a beam 21 of the base plate 1, and a stripping
apparatus operably designated 15'.
26 The base plate 1 is brought into stripping position in such
27 a manner that its lower edge is carried on the conveyor 29 and
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1 both sides of the beam 21 are held by guide bars 30. The
2 stripping apparatus 15' is disposed at a position opposite to the
1 base plate 1 as aforesaid, said apparatus lS' including a pair of
4 stripping members 8 and 8' located on either side of the base
plate 1, a cylinder for actuating said members 8 and al, and two
6 cam plates 7 and 7' for changing the spacing between members 8
7 and 8'. In this embodiment, members 8 and 8', being formed from
8 a spring material, are biased away from each other and
9 consequently, if there is no external force exerted thereon,
wedges 10 and 10' will be urged away from the base plate 1.
11 Reerence numeral 28 denotes a guide frame for the bracket 27 to
12 which a cylinder 19' is secured. The cam plates 7 and 7'
13 illustrated in Fig. 15, which are located outside of members 8
14 and 8' and mounted on the bracket ~7 by the aid of a supporting
bar 31, as shown in Figs. 16 to 19, are provided at the inside
16 lower ends with higher-profile portion 16 and 16' and at the uper
17 parts with lower-profile portions 18 and 18'.
18 The stripping operation according to the present embodiment
19 will be explained hereinafter mainly with reference to Figs. 16
to 19.
21 In Figs. 16 to 19, Figs. 16(a~ through l9(a) indicate the
22 relative positions between wedges 10, 10' and the base plate 1
23 and Figs. 16(b) through l9(b) illustrate the relative positions
24 between members 8, 8' and the respective parts of cam plates 7,
7' for the various positions of members 8 and 8' designated by
26 XVI to IXX in Fig. 15.
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1 As is evident from the foregoing, this embodiment is
2 different from the embodiment described above in that members 8
3 and 8' move linearly downwardly in a vertical direction.
4 otherwise, this embodiment is similar in respect of the way cam
plates 7, 7' act upon members 8, 8' the details of ~hich will
6 therefore not be repeated.
7 ~lthough particular preferred embodiments of the invention
8 have been disclosed hereinabove for purposes of illustration, it
9 will be understood that variations or modifications thereof which
lie within the scope of the invention as defined by the appended
11 claims are fully contemplated. For example, it may be noted that
12 in Figs. 20 and 21, there are indicated base plates 1 provided
13 with differently shaped insulating materials 4. Furthermore, the
14 use of a cylinder as a driving means and a cam plate as a
controlling means may be substituted by any other means which can
16 result in a similar performance and which will readily be
17 apparent to those skilled in the art.
