IMPROVEMENTS IN MACHINERY OR APPARATUS FOR COATING IRON PLATES WITH TIN OR OTHER METAL OR METALS, AND FOR CLEANSING SUCH PLATES
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by David Davies at the Office of the
Commissioners of Patents on the 30th November 1878.
DAVID DAVIES, of Crumlin, in the County of Monmouth, Mechanical Engineer.
"IMPROVEMENTS IN MACHINERY OR APPARATUS FOR COATING IRON PLATES WITH
TIN OR OTHER METAL OR METALS, AND FOR CLEANSING SUCH PLATES."
The object of this Invention is to improve, simplify, and cheapen the process of
coating iron plates with tin or other metal or alloy of metals, and for cleansing
such plates from oxides, scruff, and other impurities before and after they are so
coated.
In carrying out the said object I construct an efficient and reliable machine and
apparatus, the chief desideratum in the Invention, that shall be capable of receiving
the plates to be coated at one end of the molten metal bath, and conveying such
plates through the same (like sheets of paper through a printing press) for continuous
delivery as finished sheets at the other end thereof without any intermediate process
of washing or dipping.
The said
The first part of this Invention consists in the application of a peculiar disc-wheel
suitable in diameter to the length or radius of the bath to be used for conveying
the plates from the grease- or flux-pot at one end through the molten metal
direct into the finishing or washing rollers at the other end of such bath.
disc-wheel is so arranged as to revolve by self-acting machinery on its axis over
the bath, and having its bottom edge just above the top of the molten metal, the
periphery of which wheel is divided into a number of spaces to suit the size of the
plates to be coated, and is drilled to receive turned pins, on which I attach self-
acting straight, quadrant, or curved fingers or levers, having their outer ends pro-
jecting from the disc-wheel equal to the depth of molten metal in the bath, and so
pivotted as to take hold of or carry with them each plate as it passes the grease- or
flux-pot at one end for conveyance through adjustable guides direct into a peculiar
grease-pot, containing the finishing rollers and washing roller-box at the other end
of the bath, when the plate is instantly taken hold of by the rollers, the self-acting
fingers release it, and then raise immediately out the molten metal and pass over
the grease-pot, and so allow the next successive plate to be similarly treated and

page_text: delivered. I am thus enabled to deal with six plates passing continuously through
the molten metal such rollers being not only expensive in first cost and mainten-
ance, but are also extremely liable to get out of order, and, as they expose a large
surface constantly revolving in the molten metal, they tend to thicken and
deteriorate it.
The moveable fingers on the disc-wheel are made self-acting in several ways, as
by springs, quadrants, tooth racks, tappets, cams, cranks, incline slides, or direct-
acting pistons working in cylinders, and any such finger may be arrested in the
bath at any part of its revolution to give time for the next plate in advance to clear
itself. When desirable or preferable to the using of the disc-wheel for feeding the
plates, a ring or rings may be used, either rigid or flexible, of similar diameter to
the said disc-wheel, but revolving with its bottom edge in or near the upper portion
of the liquid bath.
I make a peculiar flux or grease-pot at the feeding end, with self-acting apparatus
to work in combination with the disc-wheel, and to deliver the plates to its self-
acting fingers, and I also convey the molten metal from the bottom of a peculiar
grease-pot at the finishing end of the bath back into such bath by means of a
syphon pipe.
The metal bath is made open at top, and may be open at one or both ends,
having suitable flanges thereon to receive the corresponding connections on the
peculiar grease- and flux-pots, but I do not confine myself to any special form of
bath, as the said machinery or apparatus may be applied to any other kind of bath
that may be preferred.
The second part of this Invention consists in applying a suitable apparatus for
cleansing the coated plates from metallic oxides, scruff, and other impurities that
may be carried forward on the plates from the grease, flux, or metal bath to the
finishing end, where I fix the said apparatus, which consists of a duplex reversible
washing roller-box, formed of one or a number (by preference five) of steel or iron
rollers or bars, round, oval, square, or other angular shape in section, placed inside
a large hollow roller or box so constructed as to receive one central and the other
four (or more or less) surrounding fixed or moveable rollers within it.
This large
roller or box is pierced on two of its sides to allow the plates to pass through it
over or under the said central roller, on which the roller-box revolves to adjust
itself or be adjusted (or may be arranged to revolve without it) to the plates, or to
reverse its action from top to bottom. By this arrangement the usual washman is 3
superceded. When desirable lateral motion may be given to the washing rollers
or bars, and they may be used without the roller-box by fixing them in suitable
end bearings so arranged for adjusting them to the plates.
The third part of this Invention consists in the method of removing the oxide of
iron from the plates to prepare them for coating, viz., by using the vapour of or 4
steam from sulphuric acid, instead of applying it in its liquid state, as now practised.
This I purpose doing by placing a small quantity of such acid in a suitable vessel
placed on the bottom of and inside the annealing pots containing the plates, which
acid when heated in the furnace will evaporate and cause the vapour thereof to
spread over the whole surface of such plates and so precipitate the oxide formed 4
thereon; or, if preferred, the acid may be evaporated in a separate vessel, and be
conveyed through a pipe to another cylinder or vessel containing the plates to be
cleansed when it is allowed to pass through such vessel; thence by an outlet pipe,
passing through water for condensing it to be again used.