IMPROVEMENTS IN APPARATUS FOR PRODUCING VARIOUS IMPRESSIONS ON LEATHER SKINS, SUCH AS SHAGREEN AND CROCODILE, BY HOT PRESSURE
Year: 1880

page_text: LETTERS PATENT to François Burc, of the City of Paris, in the Republic of
France, Morocco Tanner, for an Invention of "IMPROVEMENTS IN APPARATUS
FOR PRODUCING VARIOUS IMPRESSIONS ON LEATHER SKINS, SUCH AS SHAGREEN
AND CROCODILE, BY HOT PRESSURE"
PROVISIONAL SPECIFICATION left by the said François Burc at the Office
of the Commissioners of Patents on the 30th January 1880.
FRANÇOIS BURC, of the City of Paris, in the Republic of France, Morocco
Tanner. "IMPROVEMENTS IN APPARATUS FOR PRODUCING VARIOUS IMPRESSIONS ON
LEATHER SKINS, SUCH AS SHAGREEN AND CROCODILE, BY HOT PRESSURE."
This apparatus consists of a cast iron frame bearing two cylinders (the upper one
heated with gas) requisite for impressing the leather skins with the required
design.
The lower cylinder is usually of cast iron, and traversed throughout its centre
longitudinally by a shaft bearing at one end the toothed wheels necessary for
working the apparatus, and at the other the governing and transmitting pulleys;
this shaft rests on the uprights of the frame in a perfectly horizontal plane.
The lower cylinder or drum is covered with gutta percha fixed with screws; and
in order that the work may be regularly and properly executed this drum is pro-
vided with one or more circular and longitudinal grooves serving as guides in
which to place each skin, and keeping the upper or heated cylinder from the lower
or drum cylinder, so that the machine works without stopping with regularity; the
skin by this means is not subjected to be burnt by any delay either in fixing or
guiding the skin.
In order to protect the gutta percha from the constant action of the heat it is
covered with leather.
The upper cylinder is hollow, and is an electrotype cylinder heated internally
with gas, and marked all round in relief to produce shagreen or other designs, and
especially designed for crocodile; this cylinder is fixed in a horizontal plane by
means of suspenders at the head of the machine, regulated by fly wheels, which fix
them with screws.
The complete apparatus may be of variable dimensions, and with a drum
cylinder with three grooves. By a single revolution of the cylinder three skins
can be impressed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said François Burc in the Great Seal Patent Office on the 22nd July
1880.
FRANÇOIS BURC, of the City of Paris, in the Republic of France, Morocco
Tanner. "IMPROVEMENTS IN APPARATUS FOR PRODUCING VARIOUS IMPRESSIONS ON
LEATHER SKINS, SUCH AS SHAGREEN AND CROCODILE, BY HOT PRESSURE."
The object of this Invention is to impress various kinds of grain on skins, such
as crocodile, shagreen, and so forth, the apparatus employed being worked by steam,
the cylinder for producing the impressions being specially constructed for heating it
by gas, which facilitates the impression of the design, and the lower cylinder being
so disposed as to prevent the skin suffering any injury or deterioration that might
result from the action of the heated cylinder.
The apparatus, which is reduced to the most simple form of construction, is
similar in many respects to a laminating apparatus, the principal features of novelty
as constituting my Invention being,-
1st. The employment of an upper cylinder constituting a galvanotype drum, so
arranged as to be heated internally with gas in its inner chamber.
2nd. The lower cylinder, whose carcass is or may be of cast iron; and for greater
solidity this cylinder, without being fluted, receives a gutta percha case merely fixed
by screws.
The special characteristics of this cylinder is that it admits of working the
machine heated as above described without any fear of deterioration or injury to
the skin; this is effected by providing the drum with one or more spaces running
longitudinally along it; these form guides in which to place each skin; these
circular and longitudinal grooves serve to keep the upper or heated cylinder from
the drum.
By this novel arrangement there is no stoppage in working the machine, the
impression of the skin is effected with the greatest regularity and with an excellence
incapable of production otherwise, the skin by this means being protected from
burning by any stoppage either for inserting a skin or guiding it whilst under
impression.
In order to thoroughly understand the nature of the combined mechanism I have
by the accompanying Drawings represented an apparatus of the description referred
to with heated cylinder, and worked by steam.
Fig. 1 is a front elevation, and Fig. 2 a side view of my apparatus. A is the cast
iron frame, on which it will be observed are mounted the two cylinders required for
impressing the skins; D is the lower drum, traversed in the centre by a shaft, one
of whose ends bears the cog wheels C necessary for working the machine, the other
the governing and transmitting pulleys B; this shaft rests on the uprights of the
frame in a perfectly horizontal plane.
It has been mentioned that this drum was covered with a case of gutta percha E
fixed with some screws, and that it was necessary, to render the work practical and
regular, to have one or more circular grooves F, forming guides in which to insert a
fresh skin after the previous one was completed.
These grooves, besides the advantages they are described as possessing, also effect
or produce all the pressure required for perfect working.
To protect the gutta percha from the constant action of the heated cylinder it
is or may be covered with leather, forming a muffle.
G is the upper hollow galvanotype cylinder, dotted in relief round its circum-
ference for producing shagreen or levant grain, and especially arranged in relief for
impressing crocodile scales; this cylinder is fixed in a horizontal plane, as shown in
the plan, by means of suspenders H, regulated as desired by two small flys and
fixing screws.

page_text: The whole apparatus would vary in size to suit requirements, and with a cylinder
or drum with three grooves or spaces three skins can be operated on by a single
revolution of the cylinder.
K are supports, and L stretchers for stretching and keeping the skin on the
drum.
I claim the drum with grooves, which latter have the imense advantage of pro-
ducing perfect and regular work, whilst protecting the skins and the apparatus from
the action of the heat when the skins to be operated on are inserted. I claim also
the galvanotype cylinder, admitting of effecting the impression of the skins by beat
rapidly, mechanically, and by steam. I claim also the stretchers L, employed for
stretching and keeping the skins on the drum.
In witness whereof, I, the said François Burc, have hereunto set my hand
and seal, this Seventeenth day of July, in the year of our Lord One thousand
eight hundred and eighty.
FRANÇOIS BURC. (L.S.)