Improvements in Sewing Machines.
Year: 1891

page_text: Date of Application. 17th Nov.. 1891-Accepted. 19th Dec.. 1891
COMPLETE SPECIFICATION.
[Communicated from abroad by THE SINGER MANUFACTURING COMPANY, of
New York, in the United States of America, Sewing Machine Manufacturers.]
Improvements in Sewing Machines.
I, ALEXANDER ANDERSON, Manager of The Singer Manufacturing Company's
Works, Kilbowie, in the County of Dumbarton, do hereby declare the nature of
this invention and in what manner the same is to be performed, as communicated
to me to be particularly described and ascertained in and by the following
statement:—
More or less trouble has been experienced with sewing machines employing
oscillating or rotary shuttles working in circular shuttle races owing to the fact
that if the free end of the needle thread be not properly secured in commencing to
sew, it may be carried into the race and cause the shuttle to bind in the race; or
should the needle or shuttle thread be broken when the machine is in operation the
same trouble is liable to occur.
This difficulty has heretofore been partly avoided by providing the race with an
elastic flange or back, but as the said elastic flange or back was attached to its
lower part, or bottom by screws the difficulty was not entirely obviated as the said
flange or back, while free to yield at its top and side portions, could not yield
sufficiently at its bottom portion to wholly prevent the shuttle from binding when
the thread or threads were drawn into the race.
My invention has for its object to entirely obviate the difficulty referred to by
providing the shuttle race with a flange plate or ring so supported as to be free to
yield or move outward away from the shuttle at all points. This result is effected
by providing the shuttle race with a loosely mounted curved plate which extends
nearly around the race and which may, therefore, be termed a ring, the said ring
being held in place by spring arms pressing against its outer face at opposite points,
so that all parts of the said ring are free to move outward or away from the shuttle,
when necessary.
In the accompanying drawings
Fig. 1 is a front view of my improved shuttle race.
Fig. 2 is a side or edge view thereof and
Figs. 3 and 4 are detail views of the ring and of a two-armed spring,
respectively.
A denotes a shuttle race such as is used in the well-known "Singer" oscillating
shuttle sewing machine, the same being provided with a suitable circular recess for
the shuttle to travel in. B is a curved plate forming nearly a complete annulus or
ring, the same being loosely fitted in a circular recess in one face (preferably the
outer face) of the shuttle race and the latter is provided with two small dowel
pins a which pass loosely through holes in the ring B.
C is a bifurcated or two-armed spring attached to the shuttle race by a single
screw c, and having the free ends of its arms arranged to press against the outer
face of the ring B at points which are preferably diametrically opposite each other,
the said arms being also preferably perforated near their ends for the passage of
the dowel pins.
The spring C has a flange c¹ at its lower side to abut against the shuttle race,
and above said flange is a vertical portion against which the under side of the head
of the screw bears; while above said vertical portion the arms of the spring
incline inwardly to press in the ring, all as clearly shewn in Fig. 2.
From the foregoing it will be apparent that the ring B which is yieldingly held
against an annular shoulder a' of the shuttle race, and which is of such interior
diameter as to retain the shuttle in the race, will be free to spring outward at all
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page_text: points when it may be necessary for it to do so by reason of the fact that any thread
may be drawn into the shuttle race, or when the shuttle race may become clogged
by dirt or lint, which would otherwise cause the shuttle to bind in the race.
I do not wish to be understood as limiting my invention to the exact details
herein shown and described as it will be obvious that other forms of springs or
spring-arms than those which I have shewn, for yieldingly holding the ring B in
place may be employed without departing from the spirit of my invention.
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,
I declare that what I claim is :-
1. The combination with a circular sewing machine shuttle race of a curved
plate or ring loosely fitted thereto, and springs bearing against the face of said ring
at opposite points to yieldingly hold the same in place.
2. The combination with a circular shuttle race, of a curved plate or ring loosely
fitted thereto and a bifurcated spring the free ends of the arms of which press
against the face of said ring at two opposite points.
3. The combination with the shuttle race A having the dowel pins a, of a
curved plate or ring B, the bifurcated spring C having the flange e¹, and the single
attaching screw c.
Dated this Sixteenth day of November 1891.
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow, Agents.