Improvements in the Tanning of Hides, Skins, and the like, for the Production of Leather, and in the Apparatus Employed therein.
Year: 1897

page_text: Date of Application, 21st Sept., 1897-Accepted, 6th Nov., 1897
COMPLETE SPECIFICATION.
Improvements in the Tanning of Hides, Skins, and the like, for the
Production of Leather, and in the Apparatus Employed therein.
I, EDWARD HENRY DEWSON of 51 South Street, Boston, and of Adams Street
Quincy, both in the State of Massachusetts one of the United States of America
Gentleman 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 old processes of tanning hides for the production of leather, the hides and
skins passed through many steps, requiring weeks and months to complete the
tanning, but recently very valuable processes have been discovered whereby the
tanning is completed in a few hours without detriment to the leather produced.
In this new quick process which is now coming rapidly into use, it is customary
to place the hides, skins, etcetera, to be tanned, in a revolving drum in the presence
of the tanning liquor..
Hi
These drums have a single compartment, and they are but partially filled with
hides and skins, so that the load always lies on the inner surface of the drum below
its axis of rotation, and as the drum is rotated slowly the material is somewhat
raised with the drum in the direction of its rotation and then falls back, the
material being consequently rolled or tumbled over. These drums as now made
are large and expensive, and the whole upper part of the drum presents unused
space, and as the load or weight is wholly below the centre of rotation of the drum
a large amount of power is required to keep the drum in motion.
I have aimed to cheapen the operation of tanning hides, skins, etcetera, by the
quick processes referred to, and I have achieved my object by producing a liquor
tight drum having a plurality of liquor-tight compartments in which the hides,
skins, etcetera, may be loaded, each compartment doing the full work of each of
the drums such as now used, these several compartments enabling the whole area
of the drum to be utilized, rather than but a small portion thereof, as heretofore
common, and as my improved drum is rotated, the hides, skins, etcetera, in each
compartment roll and tumble one over the other in the proper manner, each mass
of hides in its own liquor, and each mass of hides will be, it will be understood,
always immersed in the tanning liquor, the hides not being removed from said
liquor during the tanning operation, such constant and uniform action of the
tanning liquor on the hides being essential for uniform, even, and quick tanning.
Increasing the compartments in the drum greatly increases the quantity of
hides, skins, etcetera, which may be treated in one and the same drum, and what
is also of great importance the loading of these multiple compartments extended
entirely about the axis of rotation of the drum, enables the weight carried by
the drum, consisting of both hides and liquor, to be so placed that the drum is
always in substantial balance, there always being hides and liquor present both
below and above the axis of the drum, and being so in balance said drum may be.

page_text: turned steadily with but the exertion of the minimum of power, and in a factory
using many of these drums the saving of power becomes a very important factor
in the cost of producing the leather.
My invention consists of an apparatus for the quick tanning of hides- and so
forth, comprising two or more, and preferably four, independent compartments,
out of communication with one another, each having a charging hole and cover
therefor, and adapted to contain tanning liquor, and hides, the several compart-
ments being arranged in a single plane and revolving about a centre in the same
path of movement the said plane and path of movement being vertical when the
apparatus has a horizontal axis of rotation as shown.
Fig. 1, of the drawing, shows in end view an apparatus embodying my
invention.
Fig. 2 a front end elevation thereof, and
Fig. 3, a section in the dotted line X, Fig 2.
The uprights A, receive the shaft or journals B, of the drum C, herein shown as
made up of boiler steel, but it may be of any other usual or suitable material, the
interior of the said drum having a series of partitions c, herein shown as four,
thus dividing the drum into a plurality of compartments.
Each compartment is accessible through a charging hole provided with a
cuver d held in place, preferably liquor tight, by a suitable locking device which
may be a bar e, one end of which enters an eye in an ear el on the drum, the other
end of the bar entering an open slot of an ear e², a set screw carried by the bar
acting on the outside of the cover d, and seating it firmly on the charging hole.
The charging holes may be located in any desired portion of each compartment.
When hides, skins, etcetera, are to be put into the drum, the latter will be
turned until two of the charging holes are brought above the centre of the drum
and then the hides, skins, etcetera, the covers being removed, will be put into the two
compartments, opened, and the liquor with which the hides, skins, etcetera, are
to be treated will be put into the said compartments and the covers will be again
applied liquor-tight after which the drum will be rotated one-half around until
the other compartments and their covers are brought above the centre of the drum
when the said covers may be removed and the new compartments thus exposed
may be filled, as stated and the covers closed, and then the drum will be rotated
at the proper speed for the desired time to let the liquor do its work.
The drum is rotated by means of a toothed wheel D which is engaged by a
pinion E on a shaft F provided with any usual fast or loose pulley.
I am aware that rotatable drums having a series of compartments for the recep-
tion of hides has been used, but in such drum the side walls of the compartments
have each been perforated to allow the tanning liquor to flow freely from one
into another of said compartments, the liquor always standing in the lower com-
partment, the hides being thus alternately covered, and then uncovered, I disclaim
such a drum as it would not be practical for use in quick tanning, for by the use
of such a drum, the hides could not be tanned uniformly, and further the liquor
always lying below the axis of rotation of the drum makes it impossible to
uniformly balance the drum as in my invention.
Other means than that shown and described may be employed for rotating the
drum.
The drum may have two or more compartments the number being immaterial
so long as there are more than one, and they are arranged upon different sides of
the axis of rotation, so that the loaded drum is substantially counterbalanced by
its load.
I do not claim an open or skeleton drum having two or more spaces, but my
invention comprehends independent and non-communicating liquor tight com-
partments.
By the use of my invention the cost of tanning is greatly reduced over old
methods, since each compartament of a drum divided into a number of compart-
ments, as set forth, equals in capacity the usual one compartment drum. Also

page_text: there is a great economy of floor space in the tannery, and there is also a saving
in driving power, both which items are of importance in any large tannery.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claita is:
An Apparatus for quick tanning of hides, skins and the like comprising a
plurality of liquor tight compartments, independent of and non-communicating
with each other, and severally having a charging hole and cover therefor, and
adapted to contain tanning liquor and hides, the several compartments being
assembled in a single plane around a common centre of motion, and means to
move said compartments in the same path of travel about said centre, substantially
as described.
Dated the 20th day of Sentember 1807
WM. BROOKES & SON,
55 & 56 Chancery Lane London, Agents for the Applicant.