Improvements in Shuttle Driving Mechanism for Sewing Machines.
Year: 1893

page_text: Date of Application, 7th Mar., 1893-Accepted, 22nd Apr., 1893
COMPLETE SPECIFICATION.
Improvements in Shuttle Driving Mechanism for Sewing Machines.
I, HARRIET RUTH TRACY of New Brighton, Staten Island, in the County
of Richmond and State of New York, United States of America 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 :-
The object of the present invention is to produce a sewing machine in which the
loop-taker or shuttle shall be driven in a positive and reliable manner to take the
loop of the thread carried by the needle, or the needle-thread, and pass it entirely
around the shuttle, to engage a thread carried by the shuttle.
The invention is illustrated in the accompanying drawings in which
Fig. 1 is a side elevation of a sewing machine embodying this invention.
Fig. 2 is a sectional view of the loop-taker or shuttle and its actuating
mechanism.
Fig. 3 is a face view of the shuttle or loop-taker, and
Fig. 4 is a face view of a depending projection from the frame of the machine,
carrying the cam by which the actuating pins are operated.
In these drawings, A represents the main driving-shaft of a sewing machine to
which may be attached, in any suitable way, the means for imparting a reciprocating
movement to the needle A².
The end of the shaft A projects beneath the work-plate of the machine and is
provided with a frame B, preferably attached to the shaft by set-screws, or if
desired, it may be permanently attached to or formed with the shaft.
The frame B is provided with radial arms which may be of any desired
number.
In the outer ends of these arms, are horizontal openings in which are permitted
to slide pins C.
Mounted upon or adjacent to the frame B, and in such manner as to revolve
with the shaft A, are bell-crank-levers D, the number corresponding to the number
of arms b, and arranged in line with such arms. Each bell-crank lever D is
pivotally connected with the pin C at one end, while the other end of each lever
projects into and is governed by the cam groove E, formed in a portion E
depending from the frame of the machine. The depending portion E' has an
opening forming a bearing for the shaft A, and the cam-groove E is of such
form that as, in the rotation of the shaft, each bell-crank-lever comes into a
position above the shaft, the end of the lever in the groove is drawn toward the
shaft, thus moving the pins C inward, and as the lever moves from the upper
position, they are each projected through the openings in the arms and outward
therefrom.
represents the shuttle or loop-taker, which is preferably of the form herein
shown, though any desired or advantageous form of shuttle or loop-taker inay be
employed. It is provided in its periphery, with three indentations forming
hooks for engaging and retaining the needle-thread and it is also provided
with a cavity in which is arranged a spindle screw-threaded at its outer end
and secured in the back of the shuttle F in any desired manner.
The spindle
serves as a shaft to retain a spool-bobbin, or the like, containing thread, and also
as a means for holding in place, a plate f which entirely closes the opening in the
shuttle or loop-taker, except for a circular passage between the plate and the loop-
taker or shuttle, through which the thread contained in the loop-taker or shuttle is
permitted to pass freely, as the loop-taker or shuttle rotates. The loop-taker is
provided with a series of openings arranged near its periphery and of a number
corresponding to the number of pins C opposite to which the openings are placed.
[P77

page_text: The loop-taker or shuttle is retained in proper operative position relative to its
driving-mechanism by a plate G mounted upon a hinged arm pivotted and supported
upon a depending portion G2 of the frame of the machine. The face of the plate G
which comes in contact with the shuttle or loop-taker, is smooth, and its edges
rounded, in order to offer no obstruction to the passage between it and the shuttle
or loop-taker, of the needle-thread.
In the operation of the device, motion being imparted through the shaft A and
intermediate mechanism to the reciprocating needle, the needle is brought beneath
the work-plate and a loop engaged by one of the hooks of the loop-taker or shuttle,
which receives motion through the pins C which enter openings in the shuttle or
loop-taker. After the loop of the needle-thread has been engaged, it is carried
around the same and spread over the face of the shuttle or loop-taker to form a
loop, and as it passes between the shuttle or loop-taker and its driving-mechanism,
no obstruction is offered, as the driving pins are withdrawn in succession leaving a
free passage for the loop of the thread.
""
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is,
A sewing machine comprising a revolvable loop-taker a driving shaft a frame
mounted on the driving-shaft pins sliding in the frame a stationary cam adjacent to
the shaft a hub mounted on the shaft and turning therewith and bell-crank-levers
bearing at one end against the cam and having each a sliding connection at its
other end with a sliding pin whereby free movement of the sliding pins is secured
substantially as described.
Dated this 7th dox of March 1802
W. P. THOMPSON & BOULT,
Agents for the Applicant.