Improvements in Driving Mechanism for Rotary Shuttles of Sewing Machines.
Year: 1891

page_text: Date of Application, 12th Feb.. 1891
Complete Specification Left, 10th Nov., 1891-Accepted, 6th Feb., 1892
PROVISIONAL SPECIFICATION.
Improvements in Driving Mechanism for Rotary Shuttles of
Sewing Machines.
I HARREY MOORE of High Street, Wellingborough in the County of
Northampton, Machine Agent do hereby declare the nature of this invention to
be as follows:-
C
This invention relates to mechanism for driving rotary shuttles of sewing
machines such as are usually mounted in a race to be rotated by a driver
extending from a rotating shaft. In operation the thread of the loop formed by
the rotating hook has to pass between the driver and the point of contact thereof
with the rotary shuttle and in this manner an uncertain strain is put upon the thread
during the formation of the stitch.
The object of my invention is to avoid the necessity of passing the thread
between the contact surfaces of the rotary shuttle and its driver. For this purpose
I provide a double driving mechanism making contact with the rotary shuttle at
two points alternately and thereby creating release from contact of the double
driving mechanism with the parts of the rotary shuttle upon which the same
operates alternately at the required time for allowing the passage of the thread of
the loop without hindrance.
Rotary shuttles for sewing machines are ordinarily rotated at a speed variable in
the course of each revolution in order that they may move the slower while the
hook takes the thread from the needle and then recover the lost time during the
remainder of their revolution. This variable speed is obtained by connecting two
lengths of shaft situated in parallel lines by means of a link, the variation in speed
at different parts of the revolution being due to the eccentricity of the centres of
the shafts so linked as each to perform a complete revolution in the same period of
time, though the shaft which derives its motion from the other by means of the link,
rotates at a speed variable throughout each complete revolution.
My invention consists in deriving from the main shaft, by means of double link
mechanism, movement for two shafts one of which being hollow is traversed by the
other placed concentrically therein. At the extremities of these two shafts I
provide projections constituting the double driving mechanism hereinafter more
fully described by reference to the accompanying drawings in all the figures of
which the same part is indicated by like reference letters.
Figure 1 is an end view of parts of a sewing machine showing the double driving
mechanism for the rotary shuttle.
Figure 2 is a side elevation partly in section and Figure 3 is a plan partly in
section of Figure 1.
Figure 4 shows the position of the links when the two members of the driving
mechanism are at their greatest distance apart.
Figure 5 shows the posicion of the links when the two members of the driving
mechanism are at their point of nearest approach.
Figure 6 shows the driving mechanism one member of which engages the rotary
shuttle to drive the same, the other being removed from contact at the point where
the hook receives the thread loop from the needle.
Figure 7 shows the driving mechanism engaging the rotary shuttle at its point
and removed from contact at the other driving end.
Figure 8 is a perspective view of the parts J K of the driving mechanism.
A represents the cloth-plate of a rotary shuttle sewing machine to which my
invention is applicable B being the needle bar and C the presser foot.
From the main shaft D I communicate a variable motion by means of cranks

page_text: and links E F to the shafts G H of the two drivers which are both supported
in the same bearing the one H traversing the one G made hollow for that
purpose.
The shafts G H being set in a line parallel with the axis of the main shaft D
but not in the same horizontal plane and deriving their motion from the said main
shaft by the intervention of cranks and links E F, each make one complete
revolution in the same period of time as that occupied by one revolution of the
main shaft but the speed of the shafts G H as compared with the speed of the main
shaft varies at different points of the revolution. As the cranks and links E F. are
connected with the main shaft D one in advance of the other the variable speed of
the shafts G H is not equally timed in both cases and consequently the driving
arm J projecting from the shaft G and the driving arm K projecting from the
shaft H during each complete revolution advance towards or recede from each
other.
This want of uniformity in the period of greatest acceleration and of greatest
retardation in speed of the shafts G and H respectively causes the driving arms J
and K alternately to make contact with the driving abutments L and M leaving an
opening free between the driver and the driving abutment upon the rotary shuttle N
first to admit the thread loop upon the rotary shuttle and then to allow it to be
released therefrom without hindrance. The driving arm J is slotted at P to allow
the required dip for the needle.
It will be seen by reference to Figure 6 that the rotary shuttle N shown in
position to receive the thread loop from the needle is driven by the driver J making
contact with the driving abutment L and leaving a clear space for entrance of the
thread loop between the driver K and the hook which receives the thread loop
from the needle. Likewise it will be seen by reference to Figure 7 that the rotary
shuttle N shown in position to release the thread loop for the completion of the
stitch by take up mechanism usually employed, is driven by the driver K making
contact with the driving abutment M and leaving a clear space for the escape of
the thread loop between the driver J and the driving abutment L.
Dated this 10th day of February 1891.
AYRTON & THOMAS,
Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Driving Mechanism for Rotary Shuttles of
Sewing Machines.
I HARREY MOORE of High Street, Wellingborough in the County of
Northampton Machine Agent 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 mechanism for driving rotary shuttles of sewing
machines such as are usually mounted in a
68 race to be rotated by a driver
extending from a rotating shaft. In operation the thread of the loop formed by
the rotating shuttle has to pass between the driver and the point of contact thereof
with the rotary shuttle and in this manner an uncertain strain is put upon the thread
during the formation of the stitch.
The object of my invention is to avoid the necessity of passing the thread
between the contact surfaces of the rotary shuttle and its driver. For this purpose
I provide a double driving mechanism making contact with the rotary shuttle at
two points alternately and thereby creating release from contact of the double
driving mechanism with the parts of the rotary shuttle upon which the same
operates alternately at the required time for allowing the passage of the thread of
the loop without hindrance.
Rotary shuttles for sewing machines are ordinarily rotated at a speed variable in

page_text: the course of each revolution in order that they may move the slower while the
hook of the shuttle takes the thread from the needle and then recover the lost time
during the remainder of their revolution. This variable speed is obtained by
connecting two lengths of shaft situated in parallel lines by means of a link, the
variation in speed at different parts of the revolution being due to the eccentricity
of the centres of the shafts so linked as each to perform a complete revolution in
the same period of time, though the shaft which derives its motion from the other
by means of the link, rotates at a variable speed throughout each complete
revolution.
My invention consists in deriving from the main shaft by means of double link
mechanism, movement for two shafts one of which being hollow is traversed by
the other placed concentrically therein. At the extremities of these two shafts I
provide projections constituting the double driving mechanism hereinafter more
fully described by reference to the drawings left with the Provisional Specifi-
cation in all the figures of which the same part is indicated by like reference
letters.
Figure 1 is an end view of parts of a sewing machine showing the double driving
mechanism for the rotary shuttle.
Figure 2 is a side elevation partly in section and Figure 3 is an underside plan
partly in section of Figure 1.
Figure 4 shows the position of the links when the two members of the driving
mechanism are at their greatest distance apart.
Figure 5 shows the position of the links when the two members of the driving
mechanism are at their point of nearest approach.
Figure 6 shows the driving mechanism one member of which engages the rotary
shuttle to drive the same the other being removed from contact at the point where
the hook of the shuttle receives the thread loop from the needle.
Figure 7 shows the driving mechanism engaging the rotary shuttle at its hook
and removed from contact at the other driving end.
Figure 8 is a perspective view of the parts J K of the driving mechanism.
A represents the cloth plate of a rotary shuttle sewing machine to which my
invention is applicable, B being the needle bar and C the presser foot.
From the main shaft D I communicate a variable motion by means of the crank
arms and links E F to the shafts G H of the two drivers which are both supported
in the same bearing the one H traversing the one G, made hollow for that
purpose.
The shafts G H being set in a line parallel with the axis of the main shaft D
but not in the same plane and deriving their motion from the said main shaft by
the intervention of the crank arms and links E F, each make one complete
revolution in the same period of time as that occupied by oue revolution of the
main shaft D but the speed of the shafts G H as compared with the speed of the main
shaft varies at different points of the revolution. As the crank arms and links E F
are connected with the main shaft D one set in advance of the other set the
variable speed of the shafts G H is not equally timed in both cases and consequently
the driving arm J projecting from the shaft G and the driving arm K projecting
from the shaft H during each complete revolution advance towards or recede from
each other.
This want of uniformity in the period of greatest acceleration and of greatest
retardation in speed of the shafts G and H respectively causes the driving arms J
and K alternately to make contact with the driving abutments L and M leaving
an opening free between the driver and the driving abutment upon the rotary
shuttle N first to admit the thread loop upon the rotary shuttle and then to allow it
to be released therefrom without hindrance. The driving arm J is slotted at P to
allow the required dip for the needle.
It will be seen by reference to Figure 6 that the rotary shuttle N shown in
position to receive the thread loop from the needle is driven by the driver J
making contact with the driving abutment L and leaving a clear space for entrance

page_text: of the thread loop between the driver K and the book which receives the thread
loop from the needle. Likewise it will be seen by reference to Figure 7 that the
rotary shuttle N shown in position to release the thread loop for the completion
of the stitch by take-up" mechanism usually employed is driven by the
driver K making contact with the driving abutment M and leaving a clear
space for the escape of the thread loop between the driver J and the driving
abutment L.
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 :-
Driving mechanism for rotary shuttles of sewing machines, consisting of two
drivers controlled from the main driving shaft of the sewing machine by two sets
of crank arms and links so as to engage alternately with two driving abutments
upon the rotary shuttle substantially as and for the purpose set forth.
Dand his 10th day of November 1901
AYRTON & THOMAS,
Agents for the Applicant.