Improvements in Lock-stitch Sewing Machines.
Year: 1892

page_text: Date of Application, 21st Dec., 1892
Complete Specification Left, 21st Oct., 1893-Accepted, 25th Nov., 1893 ·
PROVISIONAL SPECIFICATION.
Improvements in Lock-stitch Sewing Machines.
I, ALFRED TOM COLEMAN, of Ivybridge, in the County of Devon, Tailor and
Draper, do hereby declare the nature of this invention to be as follows:-
This invention relates to that class of lock-stitch sewing machines in which an
ordinary reel is used as well for the under as for the upper thread, that is to say, in
which two reels are employed instead of one reel and a shuttle, spool or bobbin.
The usual take-up is dispensed with.and the thread is drawn through the eye of the
needle once only.
In a machine constructed and arranged in accordance with this invention the reel
of under thread is placed on a spindle in a holder situated below the bed-plate, and
the thread is conducted direct to the material to be sewn. The upper thread is
always kept tight from the reel to the needle. The reel held in place by a spring
or its equivalent. As the loops are formed at the needle, a barbed hook carried on
the end of an oscillating shaft engages in turn with each loop and spreads it over
the holder.
On arriving at a given point in its travel the hook becomes free of the loop and
returns to engage with the next loop formed at the needle. The second loop is
carried round the reel-holder in the same way, as that first above mentioned, and
by the same movement of the hook the previously formed loop is drawn tight in the
material being sewn, thus completing a lock-stitch. No take-up is used and,
accordingly, the friction of the needle thread appertaining to the use of a take-up
and due to drawing the thread through the eye of the needle so many times is
obviated.
The loops are guided in their passage over the holder by a ridge provided for
the purpose on the holder which is also so shaped as to prevent the loops slipping
off the hook until the latter has arrived at the proper point therefor in its travel
about the holder.
The latter is provided with a groove or channel for carrying off oil or other
lubricant and so preventing soiling of thread.
Dated this 20th day of December 1892.
NICHOLAS WATTS,
Agent.
COMPLETE SPECIFICATION.
Improvements in Lock-stitch Sewing Machines.
1, ALFRED TOM COLEMAN, of Ivybridge, in the County of Devon, Tailor and
Draper, 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 relates to that class of lock-stitch sewing machines in which an
ordinary reel is used as well for the under as for the upper thread, that is to say, in
which two reels are employed instead of one reel and a shuttle, spool or bobbin.
The usual take-up is dispensed with and the thread is drawn through the eye of the
needle once only.
In a machine constructed and arranged in accordance with this invention the reel
of under thread is placed on a spindle in a holder situated below the bed-plate, and
the thread is conducted direct to the material to be sewn. The upper thread is
always kept tight from the reel to the needle. The reel is held in place by a spring
.

page_text: or its equivalent. As the loops are formed at the needle, a barbed hook carried on
the end of an oscillating shaft engages in turn with each loop and spreads it over
the holder.
On arriving at a given point in its travel the hook becomes free of the loop and
returns to engage with the next loop formed at the needle. This second loop is
carried round the reel-holder in the same way as that first above mentioned and, by
the same movement of the hook, the previously formed loop is drawn tight in the
material being sewn, thus completing a lock-stitch. No take-up is used and,
accordingly, the friction on the needle thread appertaining to the use of a take-up
and due to drawing the thread through the eye of the needle so many times is
obviated.
The loops are guided in their passage over the holder by a ridge provided for
the purpose on the holder which is also so shaped as to prevent the loops slipping
off the hook until the latter has arrived at the proper point therefor in its travel
about the holder.
In the accompanying sheet of illustrative drawings,
Fig. 1 represents, in reverse plan, part of a sewing machine constructed and
arranged in accordance with this invention.
Fig. 2 is a longitudinal section.
Fig. 3 represents a plan of the needle plate and shows the shape of the hole for
the needle and for the loops of the needle thread:
Fig. 4 is an end view of the holder of the reel of under thread. It shows also
the holder carrier, and the hook which engages with and spreads the loops of the
needle thread as hereinafter described. The needle plate is shown in section.
Fig. 5 represents the reel holder in section.
The reel of under thread is supported on a horizontal hollow spindle a¹
extending outwards from the inner end of the holder 6 contained in the carrier c
bolted to a support secured to the frame. The reel a is kept in place on the
spindle a by a spring pin a². The barbed hook d is carried on one end of a shaft e
which is oscillated or rocked alternately in opposite directions by means of a cam,
eccentric, crank or other well-known device actuated from the driving wheel shaft.:
The shape of the hook is seen more particularly at Figs. 1, 4 and 5. As each loop
of the needle thread is formed, as is well understood, at the needle, the hook d
working about the holder enters the loop, nose or point first and advances so as to
carry the barb beyond the loop. When thus advanced the hook recedes and the
loop being in engagement with the barb is spread over the holder b. The spreading
action continues until the hook has travelled to its lowest limit as seen in dotted
lines at Fig. 4 in which the needle thread is indicated by the letter & and the under
thread by the letter y. The hook now returns towards the needle leaving the loop
spread on the holder as seen at Fig. 4. On again arriving at the needle the hook
enters a fresh loop which it spreads over the holder in the same way as that above
described and the previously made loop resuming its journey is tightened in the
material being sewn, and so on for each loop in succession. It will be seen that as
the loops are tightened by the hook the use of a take-up for that purpose is
dispensed with. Consequently, the thread is not subjected to the friction due to
passing backwards and forwards as heretofore-in some cases several times-
through the needle eye. From the reel on which it is wound the needle thread
after having been passed through a suitable stop tension is conducted to a tension
regulator so situated as to be slightly below the level of the needle-bar top when
fully raised. From the tension regulator the thread is conducted to and passed
through an eye on the top of the needle bar and thence down to the eye of the
needle. It is always tight between the reel and the needle eye. The under thread
is, as is well understood, embraced by the loops.
The holder is shaped to present a ridge for the purpose of guiding the loops
in their passage over the holder and at the lower end of the said ridge a groove b
commences into which the barb projects thereby preventing the thread from leaving
the hook until the proper point is reached. This will be more clearly understood

page_text: by reference to Figs. 4, 5 and 6 of the drawings, of which Fig. 6 represents a cross
section of the holder of the under reel a.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a two-reel lock-stitch sewing machine the provision of a barbed hook such
as d, arranged to oscillate about the reel holder supported in a carrier such as c,
the said hook being fitted to engage with and spread over the holder the loops
formed at the needle, each loop being drawn tight as the next in succession is being
spread and the employment of a take-up avoided.
2. The barbed hook d shaped snbstantially as shown and so set on its shaft e and
arranged to operate about the under reel holder that after the nose of the hook has
entered each loop of the needle thread in turn, the barb in receding engages
therewith and draws the loop over the holder b as set forth.
3. The holder b, for the reel of under thread, with ridge band groove b³, shaped
substantially as hereinbefore described and shown in the accompanying drawing
and for the purposes specified.
Dated this 18th day of October 1893.
NICHOLAS WATTS,
Chartered Patent Agent.