Improvements in Sewing Machines.
Year: 1890

page_text: Date of Application, 29th Oct., 1890-Accepted, 29th Nov., 1890
COBIT LELE DIECIFICATION.
Improvements in Sewing Machines.
I, WILLIAM HARVEY INSLEE, of Kilbowie, in the County of Dumbarton, Sewing
Machine Expert, do hereby declare the nature of this invention and in what manner
he same is to be performed, to be particularly described and ascertained in and by the
ollowing statement
--
This invention relates to sewing machines having oscillating shuttles and it con-
ists of improvements in the construction of the shuttle and other parts connected
herewith as hereinafter described with reference to the accompanying drawings
n which
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1
CONT LELE SI CITICATION.
Improvements in Sewing Machines.
I, WILLIAM HARVEY INSLEE, of Kilbowie, in the County of Dumbarton, Sewing
Machine Expert, do hereby declare the nature of this invention and in what manner
he same is to be performed, to be particularly described and ascertained in and by the
following statement :-
This invention relates to sewing machines having oscillating shuttles and it con-
ists of improvements in the construction of the shuttle and other parts connected
herewith as hereinafter described with reference to the accompanying drawings
n which
Figure 1 is a face view of the shuttle race showing the improved shuttle and
bobbin case therein.
Figure 2 a vertical section of the same.
Figure 3 a face view and Figure 4 an end view of the shuttle.
Figure 5 a back view of the shuttle with the back plate and bobbin case supporting
pin removed.
Figures 6 and 7 front and side elevations of the bobbin case.
Figures 8 and 9, similar views of another form of bobbin case and
Figure 10 an elevation shewing the end of the bobbin.
The shuttle is composed of a half ring or segment A, of approximately T section to
which is attached the usual back plate A', having on it the pin b, which supports the
bobbin case B. The bobbin case is held in place by an arm C, which is so pivoted
to the web a, of the shuttle that it can be swung to the position shewn in dotted
lines at Figure 3, to permit of placing the bobbin D, and bobbin case on the pin b,
and then be swung into the position shewn in full lines to retain the bobbin and
case in place. The arm C, has formed at its end a delivery eye c, through which the
bobbin thread passing from the tension device d, is led and which tension device as
indicated at Figures 6 to 9 may be either on the face or edge of the bobbin case B.
The thread delivery eye is situated near to the centre of the bobbin case so that
whilst in the oscillating movement of the shuttle in its race strain will be applied to
the bobbin thread at the proper times to tighten the stitch and to draw off sufficient
thread for the ensuing stitch such strain will not as is the case when the thread is
drawn from a point at or near the periphery of the bobbin case be so great or so
sudden as to break the thread.
The position of the delivery eye relatively to the shuttle and the degree of
eccentricity are such that as diagrammatically indicated at Figure 11, the bobbin
thread passing through the delivery eye is drawn to tighten the last formed stitch
in the fabric F, by the shuttle reaching the limit of its backward movement and as the
needle comes down it clears the shuttle thread, whilst on the forward movement of
the shuttle the thread slackens off as the feed of the fabric takes place and the needle
rises the continued forward movement of the shuttle drawing off the thread from
the bobbin for the next stitch. The edge of the delivery eye piece C, is suitably
formed and rounded off at c', to serve as a thread guide in addition to its function
as a delivery eye and retaining latch for the bobbin case. At its pivoted end the
arm C, is formed with a heel at 2, to bear hard against the flange of the shuttle
ring and serve as a stop against movement of said arm in either direction beyond the
positions shewn in full and dotted lines at Figure 3. The pin e, upon which the
arm C, is pivoted to the shuttle body is formed with a groove into which is fitted the
forked end of a spring blade g, pivoted at g', to the shuttle web. This blade 9,
which is slightly bent bears at or near its mid length on a part g², of the web and
a degree of leverage is thus imparted to the forked end engaging the pivot pin e,
whereby the inner bearing face of the arm c, is retained in close frictional contact
[Price fid

page_text: with the shuttle web notwithstanding any wear that may take place, and the arm C, is
firmly retained in place after positioning the delivery eye c.
In shuttles in which the bobbin case is retained in place by gravity or when a
hobbin case retaining latch is used and the arm C, is not available the thread
delivery eye or guide (c) may be formed in or on the bobbin case supporting pin b,
at a point contiguous to the centre of oscillation.
For lightness and for the purpose of enabling the operator to ascertain the
amount of thread on the bobbin at any time without taking it out of the shuttle and
case a series of orifices h, are formed in the ends of the bobbin as shewn at Figure 10,
and in the bobbin case a number of orifices, are also formed through which
orifices the thread on the bobbin may be viewed.
The bobbin case is otherwise of ordinary construction and is fitted with e
usual finger b', which is engaged and positioned by an open skeleton bridge piece I,
This
secured by screws and distance pieces i, to the cover of the shuttle race.
open skeleton form of bridge permits of ready access to the shuttle and enables it
to be examined without removal from the race.
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed I declare that what I claim is :—
1. In a central bobbin sewing machine shuttle the provision of a thread delivery
eye or guide at a point contiguous to the centre of oscillation of the shuttle whereby
the tightening of the stitch, slackening of the loop, and drawing off the thread from
the bobbin are controlled by the movement of the shuttle substantially as described.
2. The combination with the sewing machine shuttle A, of the arm C, pivoted
thereon and serving to retain the bobbin case in place and as a thread guide and
delivery eye substantially as described.
3. The combination of the shuttle A, the arm C, pivoted thereon and spring
blade g, engaging the pivot pin of said arm substantially as described.
4. In a sewing machine shuttle a perforated bobbin case in combination with a
central bobbin having perforations in its ends substantially as and for the purpose
set forth.
5. In a sewing machine the skeleton bridge I, constructed and fitted substantially
as deseribad