IMPROVEMENTS IN SEWING MACHINES
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the Office
of the Commissioners of Patents on the 1st September 1881. A communi-
cation from abroad by Hiram Bond, of Haverhill, Massachusetts, United States
of America.
[A
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, and Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN SEWING MACHINES."
communication from abroad by Hiram Bond, of Haverhill, Massachusetts, United
States of America.]
This Invention relates to that class of sewing machines which are provided with
duplicate sets of stitch forming mechanism adapted to form two parallel rows of
stitches simultaneously, and laterally adjustable so as to form the said rows at any
desired distance apart. Such machines being known as "twin sewing machines,"
and used largely in stitching seam covering stays to the uppers of boots and shoes,
the two rows of stitches required to attach the stay to the two parts connected by
the seam being made simultaneously.
The first part of the said Invention has for its object mainly to enable the
work to be easily and accurately guided during the operation of attaching an
inside seam covering stay, and consists in the provision of a roller journalled in the
ends of the twin presser feet of a machine of the class above specified and provided
with a peripheral rib adapted to run in the groove formed in the outer surface of
the seamed part of a boot or shoe upper to which a stay is to be attached, and
thereby guide these parts by the seam while the stay is being stitched.
The second part of the said Invention has for its object to enable an outside
seam covering stay to be readily and conveniently attached to a boot or shoe upper
by a machine of the class aforesaid, and consists, first, in the hereinafter described
formation of the inner sides of the twin presser feet of such a machine whereby
the said feet are enabled to guide the opposite edges of an outside stay; secondly,
in the provision of an auxiliary presser foot adapted to hold down the stay behind
the needles; and thirdly, in the provision of a slotted guide adapted to guide the
unattached part of the stay in front of the needles.
The needles, the presser feet, the feed dogs, and the shuttles form two separate
sets of stitch forming mechanism, which sets are movable toward and from each

page_text: other. The presser feet are adapted to be raised and lowered together to release
and hold the work, and to be raised and lowered independently to a slight extent to
accommodate each foot to a thickness of work varying from the thickness under
the other foot.
The outer ends of the presser feet are provided with upwardly projecting ears
having substantially vertical slots located in front of the needles, and in these slots
is placed the arbor of a roller interposed between the presser feet in front of the
needles; the said arbor is elongated so that it will permit any desired separation of
the presser feet without losing its bearings in the same.
The aforesaid arbor is movable vertically in the slots, and pressed downwardly
by springs attached to the feet; the said springs allow the roller to have a yielding
movement independent of the presser feet so that the said roller can yield or adapt
itself to the thickness of work between but not under the feet. The said roller is
provided with a peripheral rib which is adapted to run in the groove formed in the
outer surface of a boot or shoe upper when the said parts are united in such manner
as to require an inside seam covering stay.
The rib running in the said groove guides the work, thereby ensuring the
formation of the two rows of stitches at equal distances from and parallel with the
seam, and also allowing additional rows of stitches to be formed exactly parallel
with the first rows; the distance between the two sets of stitch forming mechanism
is changed after the first rows are formed and the roller is adjusted by means
hereinafter described, so that its rib is equi-distant from the two presser feet as last
adjusted, the second rows of stitches are therefore guided by the same means as the
first rows, and their parallelism with the first rows is assured.
To secure the said rib at a point equi-distant from the presser feet, I employ a
collar adapted to be adjusted on the arbor and held at any desired point thereon by
a screw. The said collar is kept from endwise movement by two slotted ears on
one of the presser feet, between which ears the said collar is interposed, so that
when the collar is affixed to the arbor it will prevent lateral movement of the
ribbed roller between the presser feet.
I prefer to employ an auxiliary presser foot located between the twin presser
feet and behind the needles for holding down the portion of the work between the
said presser feet. This auxiliary foot is adapted to rise and fall with the other
feet like the roller, it has an independent yielding movement and is adapted to be
adjusted laterally so as to remain equi-distant from the said feet when the distance
between them is varied.
In carrying the second part of my Invention into practice I employ the needles,
the presser feet, the feed dogs, and the shuttles as described with reference to the
first part of my Invention, the presser feet having the upwardly projecting slotted
ears; in these slots is placed a slotted bar or plate, the said plate being interposed
between the presser fect in front of the needles. This plate is elongated so that it
will permit any desired separation of the presser feet without losing its bearings
in the said feet. The said plate is movable vertically in the slots and pressed
downwardly by springs attached to the feet; the said springs enabling the plate to
have a yielding movement independent of the presser feet, so that the said plate
can adapt itself to any thickness of work between but not under the said
presser feet.
The aforesaid plate is provided with a slot which is adapted to receive the
outside seam covering stay. The said stay passes through the slot to the needles
and is guided thereby, so that the unattached portion of the stay will not be pulled
upward by the needles.
The presser feet are extended inwardly on their sides sufficiently to enable the
extended edges to form guides for the edges of the outside stay. The said guides
assist the operator in guiding the work.
An auxiliary presser foot is located between the twin-presser feet behind the
needles for the purpose of bearing on the outside stay and holding down the work,
so that it will not be liable to rise or bulge upwardly between the presser feet.

page_text: This auxiliary presser foot is provided with a vertical shank which is vertically
movable in a socket in a block supported by lateral arms projecting into orifices in
the shanks of the twin presser feet, the auxiliary foot being adapted to rise and
fall independently of the said block and of the feet. A spring interposed between
the auxiliary foot and the block gives the said auxiliary foot a downward yielding
pressure. The aforesaid block is adapted to rise and fall with the twin presser
feet. In applying an outside stay to the upper of a boot or shoe by means of the
duplicate stitch forming mechanism, the inwardly extended edges of the presser
feet, the auxiliary presser foot, and the slotted plate enable the operation to be very
accurately and conveniently performed.
The aforesaid block can be moved laterally by sliding its arms in the orifices of
the twin presser feet, so that the auxiliary presser foot can be kept in a central
position when the distance between the feet is changed. A set screw in one of the
presser feet bearing upon one of the said arms keeps the auxiliary presser foot from
lateral movement when it is properly adjusted.