IMPROVEMENTS IN MACHINERY FOR STRETCHING HIDES OR SKINS
Year: 1885

page_text: I, GEORGE CUMBERPATOH of 11 Little Queen Street Storeys Gate Westminster
in the County of Middlesex Mechanical Engineer do hereby declare the nature of
this invention for "IMPROVEMENTS IN MACHINERY FOR STRETCHING HIDES OR
SKINS" and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:—
The
The efforts made to replace by machinery the method of stretching skins in the
process of tanning and manufacturing leather have not yet been successful
stretcher having to be pressed on the skin with great force and the "way" to be
made by it on large skins being of some length the arms supporting the stretcher
must be of considerable strength and weight or they will deflect-In the machines
hitherto employed plyers with long and heavy arms have been used the lower arm
supporting the stretcher and the upper arm a pressing roller between which, the
leather retained on a table was dressed whilst the plyer moved to and fro in a
horizontal direction being closed mechanically on its forward movement and
opened on its return As great power is needed to keep the plyer closed the
constituent parts of this mechanism has not yet proved successful-By the
arrangement shewn on the accompanying drawings better results are obtained, the
closing of the plyer being made not as heretofore outwardly of the working arms
and behind their fulcrum but directly on, their free extremity almost above the
point between the stretcher and the pressing roller.
In the accompanying two sheets of drawings.
Fig 1 shews a side elevation of the Machine and Fig 2 a plan.
A is a frame of cast iron carrying in front the table B. which has an opening B¹
for the passage of the plyer-On the front edge of the table a rubber bolster C is is
provided to prevent the leather from sliding the workman leaning with his body
against it to hold it fast during the process of stretching The principal body D. of
the plyer supported by the alide bars E forms a sort of lying U shaped piece
made of cast iron to which the lever F imparts a see saw motion which lever
having its fulcrum at the point G gets its motion from the crank shaft H and
connecting rod I-The crank shaft H is worked by an ordinary wheel gearing and

page_text: pulley The arrangement mentioned above so far does not differ from those already
known and used-I will now describe the improvement-The arms of the plyer D
bear in front the parts for working the leather the upper arm by means of the
joint K carries the pressing roller L made of rubber and the lower arm by means
of the joint M the supporting bar and the stretcher of steel 0-The joints K and
M are connected with the mechanism for opening and closing the plyer by rods P
and Qwhich can be lengthened or shortened by right and left hand screw nuts P¹
Q-The mechanism for opening and closing the plyer is composed of two small
crank shafts R and S lodged in the body of the plyer and connected by cog.
wheels R¹ S¹ keyed on the outside ends respectively by those shafts R¹ being a
little larger than S¹ as the joint K connected, by rod P with shaft R has to make
more way than the joint M connected by Rod Q with shaft S-By this arrangement
the roller L is lifted far enough from the table when the plyer is opened to allow
of the workman freely moving the skin on the table-The shaft R carries outside
the body of the plyer (on the opposite end to the wheel-R) a short crank arm T
the pin of which is lodged in a sliding bush U which during the to and fro motion
of the plyer slides on the horizontal Rod V following the motion of the plyer-
The rod V supported by the links V1 V₁ gets by the excentric Wand the rod X.
during the forward movement of the plyer a lowered and during the return a
raised position It results therefrom that during the going the sliding bush V will
hold the arm I down and consequently the shafts R. and S will draw back the
joints K and M by means of the rods P and Q and keep the plyer closed so that
the leather is stretched out while during the return of the plyer the horizontal
rod V in its elevated position raises the arm T by means of the sliding bush U and
consequently the crank shafts R and S turn the joints K. and M from one another.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim as the invention communicated to me is
1. The arrangement for opening and closing the plyer close to the point of
operation composed of the joints K and M the rods P and Q and the crank shafts R
and S lodged in the body D of the plyer and moving to and fro with the plyer
substantially as herein described and shewn in the accompanying drawings.
2. The combination of the Arm T of the upper crank shaft R with a horizontal
bar attached to the frame by means of a sliding bush U for the purpose of keeping
the plyer closed during the whole way in one direction and open during its return
substantially as herein described and shewn in the accompanying drawings.
Dated this 15th day of Inne 1885