other Purposes.
Year: 1885

page_text: other Purposes.
We, JOSEF FLIEGEL and EDUARD PUTTMANN, respectively engineer, and factory
director, of Hagen in the Province of Westphalia, Empire of Germany, do hereby
declare the nature of said Invention for ROOFING, FORMED. BY
ENAMELLED SHEET IRON, to be as follows:-
PLATES OF
This invention relates to a process and apparatus for enamelling iron and steel
and is chiefly appliable for the production of enamelled roofing tiles.
The onamel-mass is composed of the following ingredients:
57,4 parts of silicic acid.
carbonate of soda.
1,15
24,08
"
"
9,9
calcium.
23
נן
nitrate of soda.-
"
"
borate of soda,
"
"
"
6,32
1,15
"
stannate of soda.
This mixture is melted in an open hearth furnace, subsequently ground when
dry, then mixed with 10. per-cent of silicate of aluminia and 0,1 per cent of
calcined borax and water, so as to form a thin paste. The colours are produced by
the means usually employed for colouring glass.
The roof plates, preferably of sheet-steel, to be enamelled, are hung radially into
a round frame and dipped into the enamel. The dipping of the frame, holding the
plates, is effected mechanically in such a manner, that the movement is quicker
when dipping in, than when taking out the plates. It is very important for the
process of enamelling, that the enamel coat of the plates be thin and especially as
uniform as possible, which uniformity, however, is never to be obtained in the
desired manner by hand work.
In order to obtain a thin and most uniform layer of enamel, a centrifugal
machine is used. The frame with the plates is hung into this machine, which
frame is made of cast iron and provided with 1 shaped radial guides. Two cast
iron angles are screwed into the slot, which angles are previously provided with
needles at all parts, which could come in contact with the plates; these needles

page_text: .
keep the plates at a distance from the angles in order to allow the enamel to cover
practically the entire surface. In the disc or frame, holding the tiles, needles are
also fastened, which press on the plates from the top, for preventing the same to
be pressed upward. When all slots or radial grooves of the frame are filled with
sheets, the frame is dipped into the receptacle filled with enamel mass, as above
described, then taken out, and subsequently put on the bottom plate of the
centrifugal apparatus, so that the sheets are standing on the bottom-plate.
Subsequently the frame with the sheets is pressed rigidly against the bottom plate
by means of hooks, which can be pressed rigidly against the frame by turning a
hand wheel, mounted on a screw-spindle, acting on a pair of levers. Thus the tiles
are rigidly secured and cannot be thrown out by the working of the centrifugal
machine. By adjusting a hand lever, one of two friction rollers can be pressed
against a friction plate, situated on the axle of the centrifugal machine, which thus
can be set in motion so as to turn either to the right or to the left, as may be
desired. For the purpose of uniform division of the enamelling mass it is necessary
to reverse the motion of the centrifugal machine. The excess of enamel laid on
and thrown off, runs out through a groove.
Now the frame with the tiles is put into the drying stove for drying the enamel,
the baking of which takes place in an oven, which is divided into 3 or 4 com-
partments or muffles. The first compartment is the drying or warming muffle,
into which the tiles are brought first. Subsequently the tiles are brought into the
second compartment, the baking muffle proper. As it is important to watch
exactly the process of baking, the latter compartment contains on each side two
tubes, which are provided at the outside with mica-discs. The third compartment
serves for tempering and the fourth compartment for cooling the enamelled tiles.
The several compartments are separated from each other by sliding doors, opening
towards the top, and the grates, on which is lying the material to be baked, are
wheeled into the different compartments. The furnace is furnished with gas firing;
the generator gases and the air enter the furnace from opposite sides, eventually
additional air inlets may be applied.
The difference between the enamel baking ovens of the known construction, and
the improved oven is, that the latter bas three muffles, situated one behind the
other, and a cooling: chamber, whereby a quicker and more rational baking is
obtained, and, by tempering-a more durable enamel, which latter quality is very
important for roofing tiles. Besides the consecutive arrangement of the muffles
causes a considerable saving of fuel, as compared with other constructions.
11
T
:

page_text: when dipping in, than when taking out the plates. It is very important for the
process of enamelling, that the enamel coat of the plates be thin and especially as
uniform as possible, which uniformity, however, is never to be obtained in the
desired manner by hand work.
In order to obtain a thin and most uniform layer of enamel, the centrifugal
machine, represented on sheet II of the annexed drawings, is used.
The frame with the plates is hung into this machine, which frame is made of
cast iron and provided with ✓ shaped radial guides. Fig. 4 shews the method
of securing the plates in the frames. Two cast iron angles b and c are screwed
into the slot, which angles are previously provided with needles at all parts which
could come in contact with the plates; these needles keep the plates at a distance
from the angles in order to allow the enamel to cover practically the entire surface.
In the disc or frame d needles are also fastened, which press on the plates from the
top, for preventing the saine to be pressed upward. When all slots or radial
grooves of the frame d are filled with sheets, the frame is dipped into the receptacle
filled with enamel mass, as above described, then taken out and subsequently put
on the bottom plate e of the centrifugal apparatus, in the manner shown by Fig. 1,
sheet II, so that the sheets p are standing on the bottom plate e. Subsequently
the frame d with the sheets is pressed rigidly against the bottom plate e by means
of the hooks f (Fig. 1.) which can be pressed rigidly against the frame d by
turning the hand wheel mounted on a screw spindle acting on the levers h
and Thus the tiles p are rigidly secured and cannot be thrown out by the
working of the centrifugal machine. By adjusting the lever m, one of the friction
plates & can be pressed against the friction plate 8' situated on the axle of the
centrifugal machine, which thus can be set in motion so as to turn either to the
right or to the left as may be desired. For the purpose of uniform division of
the enamelling mass it is necessary to reverse the motion of the centrifugal
machine. The excess of enamel laid on and thrown off runs out through the
groove g.
Now the frame d with the tiles p is put into the drying oven for drying first
the enamel, the baking of which takes place in the oven shown by sheet I, this
oven is divided into 3 or 4 compartments or muffles. The first compartment I is
the drying or warming muffle, into which the tiles are brought first. Subsequently
the tiles are brought into the compartment II, the baking muffle proper.. As it is
important to watch exactly the process of baking, the latter compartment contains
on each side two tubes S. (Fig. 4), which are provided at the outside with mica
discs. The compartment III serves for tempering and the compartment IV for
cooling the enamelled tiles. The several compartments are separated from each
other by sliding doors T (Fig. 3), opening towards the top, and the grates, on
which is lying the material to be baked, are wheeled into the different compart-
ments. The furnace is furnished with gas firing; the generator gases enter the
furnace at G, the air at L (Fig. 3), eventually additional air-inlets L' (Fig. 1) may
be supplied. A C in Fig. 3 is the outlet and R the cleaning canal. The travel of
the gases of combustion is shown in the drawing by arrows.
The difference between the enamel baking ovens of the known construction and
the improved oven is that the latter has three muffles, situated one behind the
other and a cooling chamber, whereby a quicker and more rational baking is
obtained and, by tempering, a more durable enamel, which latter quality is very
important for roofing tiles. Besides, the consecutive arrangement of the muffles
causes a considerable saving of fuel, as compared with other constructions.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what
I claim is:
B
1.) The manufacture and employment of enamelled sheet iron plates or tiles for
covering roofs,. towers and walls..

page_text: 2.) The application of the enamelling process described for articles of iron or
steel in general.
3.) The construction of the centrifugal equalizing apparatus with slotted frame d,
clamping device f h h¹ r, and the friction discs 8 8 8 adapted to reverse the motion
of the apparatus.
4.) An enamel-baking oven having three consecutive muffles I, II III and
a cooling chamber situated behind the muffles, substantially as described and
illustrated.