Improvements in Sewing Machines.
Year: 1886

page_text: Date of Application, 10th Aug., 1886.
Complete Left, 10th Mar., 1887.
Complete Accepted, 10th June, 1887.
PROVISIONAL SPECIFICATION.
Improvements in Sewing Machines.
1, JOHN JAMES ROBINSON of 15 Brownswood road, Brownswood park in the county
of Middlesex Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to. lock stitch sewing machines and is designed to render the
same easily portable, of light weight, of cheap construction and readily attachable by
clamps to a table.
I drive the said machine, by a hand wheel and rotating shaft carried in bearings
under the sewing table, attached to a vertical frame. On a disc fixed to the said shaft
is fitted a pin, working in a transverse slot or dog-crank on the needle bar, which is
thus caused to reciprocate and is vertically guided in the main frame.
I so arrange the said transverse slot or dog-crank that the needle bar is caused to
make a slight rise above its point of lowest travel, to form a loop for the shuttle to
pass through, and there to remain stationary, or to once more descend to its lowest
point of travel, before completeing its up stroke.
I, utilize the same or another pin on the disc, of the driving shaft to throw over a
sliding shuttle under the working table and also by a bell crank pivoted at any
convenient point to cause the return of the said shuttle, or vice-verså.
The usual presser feed movement, and thread tensions on the shuttle and upper
bobbins are fitted in any convenient and known manner to make the sewing machine
complete.
A pair of clamping jaws with a set screw, project from the frame by which it may
be attached to an ordinary table.

page_text: I, JOHN JAMES ROBINSON, of 15 Brownswood Road, Brownswood Park, in the
County of Middlesex, Engineer, 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 :-
My invention relates to lock stitch sewing machines, and is designed to render the
same easily portable, of light weight, of cheap construction, and readily attachable by
clamps to a table.
In order that my invention may be the better understood I now proceed to describe
the same in relation to the drawings hereunto annexed reference being had to the
letters and figures marked thereon.
.
Figure 1 is a front elevation of my improved machine.
Figure 2 is a side view of the same.
Figure 3 is a front elevation of an equivalent modification.
I drive the said machine by a hand wheel A and rotating shaft a carried in bearings
under the sewing table B attached to a vertical frame C of any convenient form which 1
shall provide a guide to the needle bar D which receives its motion direct from the
said rotary shaft a by a crank pin or connecting rod or mechanical equivalent.
I carry out the operations of my machine as follows:-
On the hand wheel or disc A fixed to the said rotating driving shaft a is fitted a
pin d, working in a transverse slot or dog crank F of the needle bar D which is thus
caused to reciprocate, carrying the needle with it, and is vertically guided in the main
frame C.
I so arrange the form of the said transverse slot or dog crank F, by providing in it
a special recess that the needle bar is caused to make a slight rise above its point of
lowest travel to form a loop for the shuttle to pass through, and there to remain 2
stationary or to once more descend to its lowest point of travel before completing its
up stroke.
I may utilize the same pin d or another pin on the hand wheel or disc A of the
driving shaft to throw over a shuttle G travelling in horizontal guides under the
working table and held by suitable spring pressure against the inner face of a
the apron H. To effect this the said pin may engage into a suitable lug or pro-
jection K projecting from a sliding carriage in which the said shuttle lies. Or,
I prefer the said pin to engage with a bell crank I pivotted on some portion of the
frame so that after the said pin d has caused the shuttle to travel backwards over the
needle the said pin d strikes the lower portion of the bell crank L to effect very a
rapidly the reverse travel of the shuttle through the loop. This reverse travel of the
shuttle through the loop may be rendered more rapid by the employment of a spring!
at the back of the throwing arm of the said bell crank L, which will cause the throw
of the shuttle so soon as the pin d has ceased to bear upon the throwing arm of the
said bell crank.
1

page_text: A pair of clamping jaws N N provided with a set screw, project from the frame by
which it may be attached to an ordinary table.
Or equivalently; I may effect the relative movements of the shuttle and needle bar
from the rotary disc E by a cam lever L pivotted on the frame which will give the
required movements to the shuttle by means of the two pins e e¹; one pin e striking
the cam face outside the pivot of the lever, so as to effect the stroke from left to
right; and the other pin e¹ striking the cam face on the inside of the pivot of the said
lever, by which the return throw is effected. A spring may be used or not with the
said cam lever L to effect rapid recoil of the shuttle through the loop if desired. The
needle bar may be driven, equivalently to the former instance, by a connecting rod N,
operated from the said driving disc E or any suitable cam movement may be
employed.
The usual known presser feed movement and thread tensions on the shuttle and
upper bobbins are fitted in any convenient known manner to make the sewing machine
complete.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed, I declare that what I claim is :-
-
1st. In a portable lock stitch sewing machine provided with clamps for attachment
to a table, the operation of a shuttle sliding horizontally under the working table in
suitable guides by a pin, bell crank, spring pressed or not, operated by a pin on the
rotating driving axis, the same rotative movement operating the reciprocating needle
bar direct by a cam slot device and pin, substantially as described.
2nd. In a portable lock stitch sewing machine provided with clamps for attachment
to a table, the operation of a shuttle, sliding horizontally under the working table in
suitable guides, by a pin or pins and cam lever, spring pressed or not, the said pins
being fitted to a rotative disc and hand wheel from which the needle bar receives its
reciprocating movement by a connecting rod, substantially as described.
101 1
1007
FELL & WILDING,
1, Queen Victoria Street, London, E.C.,
Agents for the Applicant.