IMPROVEMENTS IN MACHINERY FOR UNHAIRING, SCOURING, AND CURRYING HIDES AND SKINS
Year: 1876

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN MACHINERY FOR UNHAIRING, SCOURING, AND CURRYING
HIDES AND SKINS." A communication from abroad by Benjamin Franklin
Larrabee, of Lynn, Massachusetts, United States of America.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 29th November 1876.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN MACHINERY FOR UNHAIRING,
SCOURING, AND CURRYING HIDES AND SKINS." A communication from abroad by
Benjamin Franklin Larrabee, of Lynn, Massachusetts, United States of America.
The preparation of skins or hides for tanning and the finishing of the tanned
skins or hides involve certain operations which have heretofore generally been
performed by manual labour, that is to say, by means of tools worked by hand.
Thus the "unhairing" has heretofore been effected by placing the hides upon a
block called a " beam," and then scraping the hair off with a concave blade called
an "unhairing knife," which fitted the curvature of the beam.
The striking, scouring, or currying, which are a series of mechanical operations
for the purpose of transforming the tanned but rough skins or hides into smooth,
shining, and pliable skins were also universally effected by manual labor. All
these operations which have to be carried on by men of great physical strength,
endurance, and of skill, only to be acquired by long and continued application, are
too slow to meet the large and constant demand for leather, and consequently render
leather too dear a commodity for such varied and indispensable application.
The object of this Invention is to effect the aforesaid operations and others of a
similar nature by machinery, thus saving labor, multiplying productiveness, and
cheapening the article produced.

page_text: the same; and Figures 3 and 4 are similar transverse sections, illustrating inodifi-
cations in the methods of presenting the skins or hides to the action of the spiral
blades of the knife cylinder.
In Figures 1 and 2, A, A, are the end frames of the machine connected by the
tie pieces B, B, and having mounted thercon in suitable bearings the apron
rolls E, F, and the knife cylinder H; G is a supporting roll placed directly beneath
the cylinder H and mounted in a movable frame, so that it may be moved towards
or from the cylinder at will; I is a rubber apron or belt passing around the rolls C
and D and between the feed rolls E and F and the supporting roll G and the knife
cylinder H, as shewn in Figure 2.
The roll C is mounted in sliding boxes which may be adjusted by means of
screws a for the purpose of taking up the slack in the apron 1. The feed roll E
and supporting roll G are covered with rubber g to render them elastic, so that
they will yield to accommodate the varying thicknesses of the skins or hides.
The cylinder H is provided with a series of blades h, projecting therefrom in the
form of spiral threads winding around said cylinder in opposite directions, or in
other words, the blades upon the right of the centre of the length of said cylinder
extend spirally around said cylinder in one direction and those upon the left of the
centre of the length of said cylinder extend spirally around said cylinder in the
opposite direction, so that where the two spirals meet at the centre of the cylinder
they form a flattened V, as shewn in Figure 1.
Motion is imparted to the knife cylinder by means of a belt acting upon the
pulley J, seen in Figure 1.
Upon the opposite end of the shaft of the knife cylinder is secured a bevel gear
wheel K, which meshes into and sets in motion another bevel gear wheel L secured
to the upper end of the inclined shaft M, having its bearings in the stands N
and N, and having secured to or formed upon its lower end the worm O which
meshes into and acts upon the worm wheel P secured to the end of the shaft of
the apron roll D, thereby imparting to said roll a revolving motion and drawing
the rubber apron I between the rolls E and F and between the knife cylinder, and
the supporting roll G placed directly beneath said knife cylinder at a speed of
about 2 inch to each revolution of the knife cylinder. The rolls E, F, are geared
together by the spur wheels b and c, and have motion imparted thereto by the
combined action of the rubber apron I and the belt Q leading from the pulley R
on the shaft of the roll D to and acting upon the pulley S on the shaft of the
roll F.
The supporting roll G is mounted in bearings formed in the frame T which is
fitted to be moved up and down upon slides d, d, projecting inward from the
frames A, A, the frame T and the roll C being lifted by means of the treadle U
and lifter toes V, V, mounted upon the rocker shaft W.
The operation of the aforesaid machinery is as follows:-The parts being in the
position shewn in the Drawing the operator places a skin in a wet state upon the
rubber apron
in front of the feed roll E, spreading it out smoothly thereon and
sets the machine in motion, and just as the end of the skin reaches the knife
cylinder he places his foot upon the treadle U and raises the roll G, carrying with
it the apron I, and the skin resting thercon till the spiral knives h strike upon the
skin, and by virtue of their spiral form acting thereon like oblique scrapers tend to
spread or stretch the skins out laterally, at the same time that they scrape off the
hair from the skin or scrape and rub down the rough surface of the skin according
to the operation that is being performed.
In the modification of this invention, shown in Figure 3, H is the knife cylinder,
constructed and operated as above described, and G is the supporting drum, about
fifteen inches in diameter, and having its periphery covered with rubber g, from
1/2 to 3/4 of an inch in thickness, for the purpose of rendering it sufficiently yielding
to accommodate the inequalities in the thickness of the skins or hides.
C, D, are the apron rolls around which passes the apron I, arranged with its
upper surface some distance below the top of the drum G, and adapted to feed the

page_text: skin or hide only to the drum, which then takes it up and carries it forward beneath
the pressure roll E, and then beneath the knife cylinder H, and then beneath the
brush F, the skin or hide being wrapped around about one-third of the circum-
ference of the drum G and spread smoothly thereon, and by virtue of the adhesion
of the wet skin to the rubber surface of the drum against which it is pressed with
great force by the pressure roll E¹ and again by the knife cylinder H, the hide is
held firmly in position on the drum against the tendency of the knife cylinder to
pull it off, the knife cylinder and the drum and the apron roll D being so geared
together that the upper surface of the apron I and the periphery of the drum G
will move in the same direction and at the same speed, and so as to advance the
skin or hide under the knife cylinder, say, about 1/2 inch at each revolution of the
knife cylinder.
F is a cylindrical brush to be driven by a belt or gearing from the shaft of the
knife cylinder, its revolution to be in the direction of the arrow and at a speed less
than that of the knife but considerably greater than that of the drum, the object
of said brush being to clean the skin or hide after it has been acted upon by the
knife cylinder.
In the modification shewn in Figure 4 the knife cylinder H is constructed and
operated in the same manner as described in connection with Figures 1 and 2, the
drum G is made much larger than in Figure 3 and the feed apron is dispensed with,
the skin or hide being placed directly upon the drum by the operator while the
drum is in motion, the operator holding the skin in position or extended thereon
till its end passes under the pressure roll E.
Motion is imparted to the drum G and the brush F by suitable belting or
gearing, so that their peripheries shall move with the velocity relative to the knife
cylinder, as described in connection with Figure 3.
The pressure rolls El in both Figures 3 and 4 are driven by frictional contact
with the drums, or they may be geared with the drums and driven positively,
thereby they are mounted in sliding boxes with a spring and set screw above said
boxes by which their pressures may be regulated in the same manner as the feed
roll E, shewn in Figure 2.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim,―
First. In a machine for unhairing, scouring, or currying hides or skins, the
combination of the cylinder provided with double spiral projecting blades and
a supporting roll or drum whose outer surface is covered with rubber or other
suitable elastic material, as above described and for the purposes specified.
Second. In a machine for unhairing, scouring, or currying hides or skins, the
combination of a cylinder provided with one or more spiral projecting blades and a
supporting roll or drum, having an elastic outer surface and mounted in a sliding
frame, and adapted to be moved to or from the knife cylinder by means of a treadle,
as above described and for the purposes specified.
Third. In a machine for unhairing, scouring, or currying hides or skins, the
combination of a cylinder, having one or more projecting spiral blades, a supporting
roll or drum directly below said cylinder, and an endless apron passing between
said knife cylinder and the supporting roll to feed the skin and present it to the
action of the spiral knives of the cylinder, as above described.
Fourth. In a machine for unbairing, scouring, or currying hides or skins, the
combination of the cylinder provided with one or more projecting spiral blades or
knives, the drum, the endless apron located at a level below the top of the drum,
and adapted to feed the hide or skin only to the drum, the pressure roll, and the
brush, all arranged as shown in Figure 3 of the Drawing, and adapted to operate
as above described for the purposes specified.
Fifth. In a machine for unhairing, scouring, or currying hides or skins, the
combination of a cylinder provided with one or more projecting spiral blades or
knives, a supporting druin, a pressure roll, and a brush, all arranged as shewn in

page_text: Figure 4 of the Drawing, and adapted to operate as described for the purposes
specified.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, the Twenty-ninth day of November, in the year of our Lord
One thousand eight hundred and seventy-six.
W. ROB. LAKE. (L.S.)