IMPROVEMENTS IN SEWING MACHINES
Year: 1876

page_text: LETTERS PATENT to William Henry Thomas, of Luxmore Street, Malpas Road,
New Cross, in the County of Kent, for the Invention of "IMPROVEMENTS IN
SEWING MACHINES."
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Soaled tho 28th July 1876, and dated the 9th May 1870,
PROVISIONAL SPECIFICATION left by the said William Henry Thomas at
the Office of the Commissioners' of Patents on the 9th May 1876.
WILLIAM HENRY THOMAS, of Luxmore Street, Malpas Road, New Cross, in the
County of Kent. "IMPROVEMENTS IN SEWING MACHINES."
The Invention has for its object improvements in sewing machines, and relates to
an improved arrangement of friction gear apparatus for communicating motion from
the driving or hand wheel to the disc wheel or pinion on the shaft of the machine.
For this purpose I form the peripheries of the driving or hand wheel and the disc
wheel or pinion, one with a V groove, and the other with a reverse V edge, to act
in combination therewith; but instead of forming the disc wheel or pinion in two
parts forced apart from each other by screws or springs, as heretofore, so as to bite
within the groove of the hand or driving wheel, I form such wheel solid, and I cause
the bite or friction between the two wheels to be effected by the weight of the hand
or driving wheel assisted by springs or levers. For this purpose I, according to one
arrangement, mount the hand or driving wheel in a lover, which is mounted on an
axis of motion, and is capable when desired of being acted upon by a screw or cam
to separate the two wheels from each other; or I form the part carrying the axle of
the hand or driving wheel as a slide, and arrange it to work in a guide. This slido
is acted upon as above described to cause the two wheels to gear together, or to
separate them from each other.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by:
the said William Henry Thomas in the Great Seal Patent Office on the 9th
November.1876.
WILLIAM HENRY THOMAS, of Luxmore Street, Malpas Road, New Cross, in the
County of Kent. "IMPROVEMENTS IN SEWING MACHINES."

page_text: The Invention has for its object improvements in sewing machines, and relates to
an improved arrangement of friction gear apparatus for communicating motion from
the driving or hand wheel to the disc wheel or pinion on the shaft of the machine.
For this purpose I form the peripheries of the driving or hand wheel and the disc
wheel or pinion, one with a V groove, and the other with a reverse V edge, to act
in combination therewith; but instead of forming the disc wheel or pinion in two
1ert forced apart from each other by screws or springs, as heretofore, so as to bite
within the groove of the hand or driving wheel; I form such wheel solid, and I cause
the bite or friction between the two wheels to be effected by the weight of the hand
or driving wheel assisted by springs or levers; for this purpose I, according to one
arrangement, mount the hand or driving wheel in a lever, which is mounted on an
axis of motion, and is capable when desired of being acted upon by a screw or cam
to separate the two wheels from each other; or I form the part carrying the axle of
the hand or driving wheel as a slide, and arrange it to work in a guide. This slide
is acted upon as above described to cause the two wheels to gear together, or to
separate them from each other.
And in order that my said Invention may be more clearly understood and readily
carried into effect, I will proceed, aided by the accompanying Drawings, more fully
Figure 1 is a side view, Figure 2 is an end view, Figure 3 is a plan, and Figure 4
is an end view with the hand wheel shown by dotted lines of parts of a sewing
machine, showing one mode of applying my improved friction gear thereto.
Figure 5 is a side view, Figure 6 is an end view with the hand wheel shown by
dotted lines, and Figure 7 is a plan of parts of a sewing machine, showing a modifi
cation in the mode of applying my improved friction gear thereto.
In all the Figures similar parts are marked with similar letters of reference.
a is the driving or hand wheel, and b is the disc wheel or pinion, which is fixed
on the axis c of the machine.
In Figures 1 to 4 the driving or hand wheel a is formed with a V groove, and
the disc wheel or pinion b with a V edge to act in combination with the groove in
the wheel a, whilst in Figures 5 to 7 the driving or hand wheel a is formed with
Vedge, and the disc wheel or pinion with a reverse V groove to act in com-
bination therewith.
Instead of forming the disc wheel or pinion in two parts forced apart from cach
other by screws or springs, as heretofore, so as to bite within the groove of the hand or
driving wheel, I form such wheel solid, and I cause the bite or friction between the
two wheels to be effected by the weight of the hand or driving wheel assisted by
springs or levers. For this purpose, according to the arrangement shown at Figures
1 to 4, I mount the axis of the hand or driving wheel a in a lever d mounted on an
axis of motion at d, and a spring d assists in keeping the hand or driving wheel a
in contact with the disc wheel or pinion b, whilst when required a screw e, or it
may be a cam, acts to raise the wheel a away from the disc wheel or pinion b.
Or, as represented at Figures 5 to 7, I form the part f, carrying the axle of the
hand or driving wheel, as a slide, and arrange it to work in a vertical guide g, and
I place underneath the slide f a spring h, which constantly acts with a tendency to
raise the hand or driving wheel a away from the disc wheel or pinion b, whilst a
lever or cam i, or it may be a screw, acts to force the hand wheel a into contact
with the disc wheel or pinion b; or, if desired, the contrary arrangement may be
adopted, that is to say, the hand wheel a may be forced into contact with the disc
wheel or pinion b by a spring, and removed therefrom by a lever, screw, or cam, as
in the arrangement shown by Figures 1 to 4.
In the arrangement shown at Figures 5, 6, 7, the disc wheel or pinion is shown
formed with a groove to enable it to be driven by a band,

page_text: Having thus described the nature of my said Invention, and tho modes in which
I propose to carry the same into effect, I would have it understood that what I
claim is, the peculiar arrangement of friction gear for sewing machines in which the
axis of the hand or driving wheel is carried by a slide or lover, and such wheel is
forced up to the disc wheel or pinion by a spring, lever, cam, or scrow, whilst it is
capable of being removed from contact therewith by a spring, screw, cam, or lever,
in manner substantially as herein shown and described.
In witness whereof, I, the said William Henry Thomas, have hereunto set my
hand and seal, this Eighth day of November, in the year of our Lord One
thousand eight hundred and seventy-six.
W. H. THOMAS. (L.S.)