Year: 1888

page_text: Date of Application, 16th Nov., 1888
Specification Accepted, 12th Feb., 1889
We, FRIEDRICH WILHELM KOFFLER, Engineer, and ADALMAR BREDEN, Manufac-
turer, both of 22 Auhofstrasse, Unter St. Veit, near Vienna, in the Empire of
Austria, do hereby declare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by the
following statement :-
In the Specification of Letters Patent No. 12485, dated October 19 1885 granted
to Friedrich Wilhelm Koffler, an improvement in the process of zincing sheet metal
is described and claimed, this improvement consisting in removing from the metal
sheet, while it is being withdrawn out of the bath of melted zinc, the surplus zinc
adhering to its sides, this being done by means of brushes.
We have since found that this process, the result of which is the formation of a
superficial layer of an alloy of the remaining zinc and the other metal, can be
used to advantage in zincing not only sheet metal, but metal articles of various
kinds.
As the alloy which is formed on the surface of metal articles thus treated has a
considerably higher melting point than zinc, metal ware treated according to the
novel method which forms the subject of this invention, may be coated, by the hot
process, viz., by immersing them in a bath of molten metal, with metals and alloys,
the melting point of which is higher than that of zinc whilst hitherto it has been
necessary to obtain this result by plating or electro-plating, as metal articles zinced
according to known methods were covered with surplus unalloyed zinc, which
became burned on the zinced article being immersed in the molten metal, and as
the zinc-ashes thus formed prevented the metal from firmly adhering to the articles
under treatment.
In carrying out our invention we find it advantageous to employ the hereinafter
described apparatus whereby the metal articles to be zinced are immersed in the
bath of molten zinc, lifted out of the said bath automatically, after a certain time, and
brushed while they are being lifted.

page_text: Each metal article or set of metal articles is immersed in the bath of molten zinc
and lifted out of the same by means of two endless chains one at each end of the
melting-pot; these chains run vertically over suitable chain pulleys and are provided
with books projecting alternately upwards and downwards. In a pair of the
corresponding upwardly projecting hooks of each chain is placed a supporting bar
from which the metal articles are suspended by means of suitable tongs; this
bar when the hooks supporting it arrive at their lowermost position is deposited upon
suitable bearings at each end of the melting-pot, by the hooks disengaging from the
said bar, which is shortly afterwards seized and lifted with the metal articles attached
thereto by a pair of reversely placed hooks.
At the same moment, two revolving cylindrical brushes, which have an endwise
to-and-fro motion imparted to them, are pressed against both sides of the metal
articles, thereby stripping all the surplus zinc back into the melting pot.
In the annexed drawings
Figure 1 is a sectional front elevation of the apparatus (on line x, x Figure 2)
having a metal sheet attached to the carrier.
Figure 2 is a plan view of the same.
Figure 3 is a sectional end elevation of the apparatus (on line, Figure 2).
Figure 4 is a sectional end elevation of one of the moveable bearings of the
brush shafts (on line, Figure 2).
Figure 5 is a sectional front elevation of the said moveable bearing, showing the
crank mechanism, by which the to and fro motion is imparted to the brush shafts (on
line ×ª³, ¿ª³ Figure 2).
Figure 6 is an elevation of the mechanism, by which the bearings of the brush
shafts are moved towards each other for the purpose of pressing the brushes against
the rising metal articles.
Figure 7 shows on a larger scale, in side elevation, the lower end of one of the
endless chains and one of the two supports upon which the bar carrying the metal
articles is resting, while the said articles are being immersed in the molten zinc.
Figure 8 shows a transverse section of the support of which Figure 7 is a side
elevation and the arm resting thereon of the bar carrying the metal articles, as well
as one of the pairs of tongs pivotted to the said bar.
Figure 9 is an end elevation of the said bar or carrier.
Figure 10 is a side elevation of one of the pairs of tongs by means of which the
metal articles are suspended from the carrier.
For the purpose of immersing the metal articles, for instance sheets H in the
molten zinc contained in the metal-pot E, chain elevators h² running over. chain
pulloys h, h¹, and provided at intervals with hooks h³, h, are mounted on each end
of the melting-pot. Two hooks located at the same height one on each chain form
a corresponding pair, and on each chain, upwardly directed hooks alternate
regularly with downwardly directed ones.
Each sheet of metal or metal article is nipped in tongs I which are pivotted to a
carrier bar I. By causing the cams of a shaft i, the bearings of which are formed
on the lower edge of the carrier I', to force asunder the upper arms of the tongs I,
the lower arms or jaws of these latter may be closed so as to hold fast the metal
shoet or other metal article previously introduced between them. For this purpose
the cam shaft i is suitably turned by means of a wrench as indicated by dotted lines
in Figure 8.
After the metal sheet or metal article is attached to the carrier bar 1, this bar is
deposited by means of its terminal aruns in a pair of hooks h³, which, on moving
downwards, have their openings directed upwards, the metal sheet H or the metal
article being in this way automatically immersed in the bath of molten zinc.
Suitably shaped supports, which are arranged on each end of the melting-
pot below the lower chain pulleys h, arrest the arms of the carrier with the
metal articles thereto attached, and the hooks ³ are then withdrawn below the said
arms *.

page_text: The metal sheet remains in the bath of molten zinc, until the next hooks h, h
the openings of which are directed downwards, arrive and seize the arins of the
carrier from the other side, so as to carry them along and lift the metal articles out
of the zinc bath.
On either side of the melting pot E, a base plate A supports uprights B, wherein
the guide ways b for the movable bearings (of the brush-shafts c are formed. To
the brush-shafts c are keyed the cylindrical brushes C, to which motion is imparted
by means of the helt-pulleys C so as to turn in the direction of the arrows a a
figure 3. In order to produce the desired effect, it is necessary that the cylindrical
brushes should receive besides their rotary movement, an end wise to and fro
motion in opposite directions relatively to each other, that is to say, one shaft should
move to the right while the other is moving to the left and vice versa.
For this purpose one end of each brush-shaft c carries an endless screw c¹ in gear
with a
worm wheel which transmits the movement by means of the toothed
wheels cand c to a vertical cranked shaft c*.
The bearings C at the ends of each shaft c are connected together by means of a
bar D, to which is mounted a bearing d' for the middle portion of the shaft this
bearing being movable along a slide-way d d. By means of a connecting rod d³, the
said bearing d is connected to the cranked shaft c, so as to be reciprocated by this
shaft. The bearing arranged in the middle of the shaft c prevents this latter from
bending.
In order to admit of the shafts e being reciprocated within the naves of the belt
pulleys and the endless, screws c', which are journalled between stationary cheeks
connected to the bars D, the ends of the said brush-shafts are provided with
longitudinal grooves c of suitable length, into which projects a key formed within
the nave of the endless screw and the belt-pulley and transmitting the movement
to the said endless screw from the pulley. As the endless screws c¹, and the belt
pulloys Care provided with tubular journals c', resting in the bearings O, wear.
and tear of these latter under the action of the end wise to and fro movement of the
shafts c is avoided. This arrangement is clearly shown in figures 1 and 2 wherein
half of one of the pulleys C is shown in section.
For the purpose of pressing the two rotary brushes C against the metal sheet H
or metal article which is just being lifted out of the melting-pot E, racks f which
are suitably guided on the standards B, are fixed to each end of the crosspieces D by
means of which the bearings C of each brush shaft c are connected to each other..
Between each pair of racks on each side of the apparatus is arranged a pinion
mounted upon the same shaft as the pinion on the opposite side of the apparatus,
and by means of a hand-wheel likewise mounted on the said shaft f
cylindrical brushes can be caused uniformly to move towards each other and in
opposite directions.
the
As on this displacement of the cylindrical brushes the mechanism by which the
shafts caro reciprocated, ought likewise to be displaced, the said mechanism is
mounted between two horizontal plates 9 which are screwed to the bearings C and
to the cross pieces D, as clearly shown in figure 4.
In the drawings we have shewn our apparatus, by way of example, adapted for
treating plates or similar articles af a flat shape. In some cases where the articles
to be treated are of other shapos, a variation in the form of the brushes and other
parts of the apparatus will be necessary but in all cases the manner of carrying out
the process will be the same, that is to say, it will consist in removing the
surplus zinc from the surface of the treated articles by means of brushes.
Having, now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
(1). In ziucing metal articles of any kind by the hot process, removing the surplus
zinc by means of brushes immediately on the metal article being withdrawn from the
hath of molten zinc substantially as "and for the nurnose described

page_text: (2). In apparatus for zincing metal articles, the combination with a melting pot
of two endless chains mounted vertically at either end of the melting pot, hooks
fixed to the said chains and alternately directed upwards and downwards, a bar
from which the metal articles to be zinced are suspended, and suitable supports for
the ends of this bar, arranged on each end of the melting pot below the endless
chains, substantially as, and for the purpose, set forth.
(3). In apparatus for zincing metal articles, the combination with a melting pot
of means for immersing a metal sheet or metal article in and lifting it out of the
same, of two rotary cylindrical brushes arranged on each side of the melting pot
and having their bearings adapted to slide towards the melting pot and in opposite
directions and of means for displacing the said boarings in their guides, substantially
as, and for the purpose, set forth.
(4). In apparatus for zincing metal articles, the combination with a melting pot
of means for immersing a metal sheet or metal article in and lifting it out of the
same, two rotary cylindrical brushes arranged on each side of the melting pot and
having their bearings adapted to slide towards the melting pot and in opposite
directions, cross pieces, which rigidly connect the bearings of each brush shaft,
racks fixed to each bearing and extending parallel with the guideways of the same
in one direction so as to be superposed on each end of the apparatus, and of two
pinions each in gear with a pair of superposed racks on each end of the apparatus
and mounted upon a common shaft, substantially as, and for the purpose, set
forth.
(5). In apparatus for zincing metal articles, the combination with a cylindrical
rotary brush, its moveable bearings and the cross-piece rigidly connecting the said.
bearings, of a vertical cranked shaft, having its bearings rigidly connected to one
of the moveable brush shaft bearings, suitable intermediate gear between the brush-
shaft and said cranked shaft so as to continuously rotate this latter, and a connecting
rod or link, connecting the crank to an intermediate point of the brush shaft, substan-
tially as, and for the purpose, set forth.
(6). The combination with metal articles to be zinced of a bar having a shaft
mounted along its lower edge, a series of pairs of tongs pivotted below the shaft
to downwardly extending projections of the said bar and of cams fixed to the said
shaft and located between the upper arms of the said tongs, substantially us, and
for the purpose, set forth.
Dated the 16th day of November 1888