Improvements in Staking Machines.
Year: 1891

page_text: Date of Application, 4th Aug., 1891-Accented, 28th Nov., 1891
COMPLETE SPECIFICATION.
[Communicated from abroad by JOHN MILES SCHOFIELD, Gentleman, of
144, Pearl Street, Boston, and ARTHUR CROSSLEY, Solicitor of Patents,
of Townsend Street, Roxbury, both in County of Suffolk, Massachusetts,
United States of America.]
Improvements in Staking Machines.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, 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:-
This invention has for its object to provide certain improvements in machines
for stretching and working tanned skins to make them soft and flexible, and by
stretching the grain or outer surface open the pores so that they will freely absorb
coloring matter; such machines being known among leather manufacturers as
"staking machines." A machine of this class has a metallic scraping blade or jaw
against which the flesh side of the skin is held, and an elastic presser or cushion
which presses the skin against said blade. Said blade and presser or cushion are
arranged to act as jaws which open or are separated to receive the skin between
them, and close upon the skin. They are reciprocated together or in unison and
are separated while moving one way and closed upon the skin while moving the
other way, the skin being held at one end by the operator against the pull exerted
on it by the closed jaws, so that the blade scrapes the skin, and the two jaws
together stretch and soften the same while they are closed upon it.
The invention relates chiefly to the construction and relative arrangement of the
said jaws, and particularly to the construction of the yielding jaw or cushion; and
it consists first, in a yielding jaw or cushion made in independently adjustable
sections, in combination with a suitably arranged scraping jaw or blade, said
sections enabling the yielding jaw to be adjusted to compensate for the varying
wear to which its acting surface is often subjected, said surface being frequently
worn away more rapidly at its central than at its end portions. This unequal
wear can be taken up by an independent adjustment of the central sections, so that
the period of usefulness of the yielding jaw as a whole is much greater than it
would be if its unworn portions had to be cut away or dressed down in consequence
of local wear not affecting the elastic acting surface, or, if the entire jaw had to be
discarded in consequence of such wear, either of which results would be likely if
the yielding jaw were in one integral piece or part, as in all machines in use prior
to this invention, so far as we are aware.
The invention also consists in the combination with the yielding jaw made in
independent sections, of means for applying an independent yielding pressure to
each section, so that the sections can yield independently and thus conform to
wrinkles and other local inequalities in the thickness of the skin.
The invention also consists in the means employed to adjustably support the
sections of the yielding jaw, and in other improvements, all of which we will now
proceed to describe and claim.
Of the accompanying drawings forming a part of this Specification,
Figure represents a top view of a scraping jaw or blade and a sectional yielding
jaw or cushion co-operating therewith, said parts embodying my invention.
Fig. 2 represents a side view of the construction shown in Fig. 1.
Figs. 3 and 4 represent respectively a top and a side view, of a set of jaws of
modified construction, the blade or scraping jaw being partly broken away in
Fio 3

page_text: Figs. 5 and 6 represent a top and a side view of another modification.
C
The same letters of reference indicate the same parts in all of the figures.
Referring first to Figures 1 and 2, a represents the blade or scraping jaw, which
is attached by bolts or screws 6 to an arm or carrier c which is connected with a
movable carriage to which a reciprocating motion may be imparted in any
suitable way.
d represents the sectional yielding jaw which is composed of sections 6, 6, 6, of
elastic vulcanized rubber or other suitable yielding material, and clamping devices
adapted to adjustably hold said sections and permit their independent adjustment.
The sections 6 are arranged to bear on the under side of the blade or scraping
jaw a near the operating edge of the latter. The clamping devices that hold said
sections are a series of pairs of pivoted levers 77' each pair being composed of a
lower lever 7 supporting one of the sections 6, and an upper lever 7¹ which is
pressed down upon the same section 6, the two levers clamping the section 6
between them. The said levers are pivoted at e to ears on an arm or carrier f
which is connected with the movable carriage above mentioned, and are provided
with means whereby their forward ends may be pressed upon the sections 6 to
grasp and hold the same, and moved apart to release said sections and permit their
adjustment, this result being accomplished by adjusting screws inserted in the
rear ends of the levers 71 and bearing upon the rear portions of the levers 7, as
shown in Fig. 2. There is a screw; for every lever 7 and when either of said
screws is turned inward or downward it separates the rear ends and forces together
the forward ends of the pair of levers to which it belongs, thus clamping the
section 6 which is between said forward ends. Either section 6 may be released to
permit its independent adjustment, by turning outward the screw connected with
the levers that support it, thus loosening the section so that it may be moved
endwise. Each pair of clamping levers is acted on by an independent spring g
which presses its grasping ends and the section 6 held thereby upwardly, to give
said section a yielding pressure on the skin between it and the blade.
There are a series of said springs 9 interposed between the rear ends of the
lower levers 7 and a yoke or frame which is mounted to swing on the pivot e that
supports the series of levers. Said frame is provided with an ear 'which is
adjustably connected with a projection f' on the arm or carrier f, by means of
screws which rigidly, yet adjustably, connect the frame h with said arm.
By
adjusting the screws i¹, the frame may be either raised or lowered, and thus
caused to decrease or increase the yielding downward pressure of the springs g on
the rear ends of the levers 7, the forward grasping ends of said levers and the
sections 6 thereon being pressed upwardly against the skin interposed between said
sections and the blade a by said pressure. The pressure of each spring may be
independently regulated by means of a series of adjusting screws m in the frame ;
said screws bearing on plates m¹ resting on the upper ends of the springs g, hence
each spring may be given more or less tension as circumstances may require, so
that if a weak place or hole should be found in the skin, the pressure on one or
more of the sections 6 may be decreased without varying the pressure on the
entire series.
The downward movement of the rear ends of the levers 7 may be limited by
stop screws k, of which there may be one for each lever 7, said screws being inserted
in the arm f.
It will be seen from the foregoing that the sections of the yielding jaw d are
adapted to be adjusted independently to compensate for wear, so that the parts of
the said jaw that are subjected to the greater wear may be adjusted without dis-
turbance of the other parts. It will also be seen that by providing the jaw sections
with a yielding pressure against the skin and with means for varying said pressure
either throughout all the sections simultaneously or in one or more independently,
the machine can be readily adapted to various qualities and kinds of stock, so that
the pressure can be made lighter when thin and delicate skins are being treated
than with stronger and heavier skins. This provision of means for imparting to

page_text: the yielding jaw sections a yielding pressure, which is variable either throughout
all the jaws at once or locally, is an important feature of the invention.
The
The holders or carriers cf, supporting the scraping jawa and the sectional jaw d,
may be operated by any suitable mechanism, said carriers forming parts of an
organized machine provided with means for closing the jaws upon a skins and
moving them simultaneously in the general direction indicated by the arrow in
Fig. 2 when they are closed, and with means for moving the jaws in the opposite
direction and at the same time separating them so that the skin or another one may
be inserted between them when they return to their starting point. The operator
holds one end of the skin in any suitable way, or by the aid of any suitable
appliances, at a point to the left of the arm or carrier c, as viewed in Fig. 2, so that
the jaws slip upon the skin as they move in the direction of the arrow.
sections 6 hold the skin closely pressed against the under side of the scraping jaw
close to the scraping edge of the latter, and thus afford a sufficient resistance to the
slipping movement of the skin between the jaws to enable the jaws to thoroughly
stretch the skin and at the same time render it pliable, both by the scraping action
of the blade on its flesh side and by the abrupt flexure of the skin over the edge of
the blade. The arrangement of the sectional yielding jaw so that it presses the
skin against the under side of the scraping jaw close to the edge thereof, enables
the skin to be bent very abruptly over the edge of the blade, as will be seen by
reference to Fig. 2, this abrupt bending giving the pores in the grain or outer side
of the skin the maximum stretching or opening.
We prefer to make the edge of the blade a convex, as shown in Fig. 1, the
yielding jaw sections being arranged on a curve corresponding to the curvature of
the said edge. This form of the edge of the blade gives a lateral stretch to the
pores of the skin, the outer surface being stretched laterally by its conformation to
the convex edge of the blade.
In Figs. 3 and 5 we show a modification in which the yielding jaw sections 6
bear on a single plate 9 which extends as one piece under the whole series of
sections, so that the sections have no independent yielding movement, excepting
that afforded by their inherent elasticity. The plate 9 is pivoted at e to ears on
the arm or carrier f and is adjustably connected at its rear end with said carrier
by screws 10, 10.
The upper levers 7 are formed and arranged substantially as shown in Figs. 1
and 2, and they are adjusted by the screws ; which bear at their lower ends on the
plate 9.
The sections 6 may be pushed forward in this modification to compensate
for their wear, by means of a rod 13 (Fig. 4) passed through one of a series of
slots 14 in the plate 9 and inserted in an orifice 15 in the lever 7' located above the
said slot, the rod 13 being then pressed against the rear end of the section 6 and
thus caused to push it forward. There should be a row of orifices 15 in each
lever 7', as shown in Fig. 3.
Figures 5 and 6 show another modification, in which the sections 6 are inserted
side by side in a holder 17 which is connected by pivots 18 with the ears on the
arm or carrier f. The sections 6 bear directly against the edge of the blade a in
this case, said blade being straight. The sections are independently adjustable
towards the blade by means of screws 19 inserted in the rear of the holder, and
bearing against the rear ends of the sections. Screws 20 inserted in the top of
the holder aid in retaining the sections at any positions to which they may be
adjusted. The holder has an ear 21 which is secured to the carrier f by screws 22, 22,
said screws enabling the holder to be turned on its pivots 18, to vary the height of
the acting faces of the sections 6.
It will be seen that in each of the above described modifications the yielding
jaw is made in sections which are independently adjustable to compensate for wear.
Other modifications may be made in the construction and arrangement of the parts
without departing from the spirit of the invention.
The sections 6, may, if desired, be provided with metal tips or terminals to bear
on the skin, said terminals being yieldingly supported.

page_text: Instead of using a series of separate springs g, we may use a continuous block or
piece of rubber extending across all the levers 7, said strip being compressed over
each lever 7 by one of the screws m, and constituting an equivalent of the series of
independent springs.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me by
my foreign correspondent I declare that what I claim is:--
1. The combination of a scraping blade or jaw, a series of independently yielding
sections constituting a yielding jaw, and means substantially as described for
adjusting said sections independently, whereby the pressure of the yielding jaw at
any point may be varied without varying the pressure at other points, as set forth.
2. In a staking machine, a flat reciprocating scraping jaw or blade having a
laterally curved convex edge projecting outwardly at its central portion farther
than at its ends, whereby said blade is adapted to stretch a skin and open the pores
thereof laterally, combined with a yielding reciprocating jaw adapted to co-operate
with said convex edge in stretching a skin laterally, as set forth.
3. In a staking machine, a flat reciprocating scraping jaw or blade having a
laterally curved convex edge projecting outwardly at its central portion farther
than at its ends, whereby said blade is adapted to stretch a skin and open the
pores thereof laterally, combined with a yielding reciprocating jaw composed of a
series of sections arranged on a curved line corresponding to the curvature of the
edge of the scraping blade, as set forth.
4. The combination of a flat reciprocating scraping blade or jaw, the series of
reciprocating elastic jaw sections arranged to bear on the under side of said jaw, or
upon a skin interposed between the jaw and sections, a series of pairs of levers
holding said sections, a carrier to which said levers are pivoted, and means for
exerting a yielding pressure on said levers and on the sections held thereby, whereby
the sections are yielding pressed against the blade, as set forth.
5. The combination of the flat reciprocating blade, its carrier, the series of pairs
of levers pivoted to another carrier, the reciprocating yielding jaw sections held by
said levers, the series of adjusting screws j whereby the said sections may be either
clamped or loosened independently, and means for exerting a yielding pressure on
said levers and jaw sections, as set forth.
6. The combination of the scraping blade, its carrier, the series of pairs of levers
pivoted to another carrier, the yielding jaw sections held by said levers, means for
clamping and releasing said sections, the pivoted frame adjustably connected to
the last named carrier, and a series of springs interposed between said frame and
the levers whereby a yielding pressure is imparted through the levers to the jaw
sections, said pressure being variable by adjustment of the frame h, as set forth.
7. The combination of the scraping jaw a, its carrier c, the carrier f having the
stop screws k, the levers 771 pivoted in pairs to the carrier f, the yielding jaw
sections clamped between the forward ends of the levers, the frame / pivoted to
said carrier and adjustably connected therewith as described, the springs g inter-
posed between said frame and the levers 7, and the spring adjusting screws m in
said frame, all arranged and operating substantially as set forth.
Dated this 4th day of August 1891.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.