Improvements in Sewing Machines.
Year: 1888

page_text: ate of Application, 23rd Nov., 1888
Complete Specification Left, 27th June, 1889-Accepted, 27th July, 1889
PROVISIONAL SPECIFICATION.
Improvements in Sewing Machines.
I, JAMES YATE JOHNSON, of 47 Lincoln's Inn. Fields, in the County of Middlesex.
Gentleman, do hereby declare the nature of this Invention, which has been com-
municated to me from abroad by the Willcox and Gibbs Sewing Machine Company.
of New York City, in the County and State of New York, in the United States of
America, to be as follows:-
This Invention relates to sewing machines and particularly to the well known
Willcox and Gibbs machine, in which a chain stitch is produced with a single thread
by the operation of a revolving looper. The improvements constituting the present
invention are as follows:-
First. In the operation of the machine it sometimes happens that the downward
motion of the feed bar by the feed eccentric is resisted by the winding up of the
thread upon the looper, or by the accidental catching of the material upon the feed
bar, and the feed motion is thereby injured. To prevent this, a shoe is interposed
between the feed eccentric and feed bar, and this shoe is constructed so as ordinarily
to remain in contact with the feed bar; but the parts are so combined and arranged
that in case of accidental interference with the feed motion, as above pointed out, the
feed eccentric and shoe can descend, leaving the feed bar at its highest point. Injury
to the feed mechanism is thereby avoided.
In carrying out the invention, the feed eccentric shoe is kept from revolving with
the eccentric by means of a projection extending into a slot in the feed bar, and the
construction of this slot is such as to permit the shoe to separate from the feed bar
and descend without it. The pressure of the spring which returns the feed bar also
aids in keeping the feed bar in contact with the upper edge of the shoe in the ordinary
operation of the machine.
In place of a slot or recess in the feed bar for the reception of the projection from
the shoe, a pin driven into the feed bar below the shoe will serve the same purpose,
but the former construction is preferred as presenting more surface for wear.
Second. In sewing machines of the type specified, motion is communicated to the
needle lever from a ball eccentric on the main shaft through a connection rod pivoted
at its upper end to said needle lever by means of a ball stud. The connection rod
consequently has a slight oscillating movement on said ball eccentric. The object of
this improvement is to allow this oscillating movement and at the same time to
prevent any oscillation of the connection rod on a vertical axis passing through its
centre from the eccentric to the ball stud. The connection rod has a counter bored
recess on one side, and in this recess projects a revolving flange or shoulder carried
by the wheel, and as heretofore made, a sufficient space has been left between this
flange and the opposite surface, or bottom of the recess, to permit the oscillation of
the connection rod.
According to the present invention the bottom of the recess instead of being a
plane surface as heretofore, so that the space between it and the said flange is of the
same width all round, has a portion or horizontal edge touching or nearly touching
the said flange on each side of the eccentric, this portion being on a transverse or
horizontal line passing centrally across the recess. From this line or edge the counter
bored face of the recess is cut away from the shoulder or flange both upward and
downward, forming a space between said face and flange which widens gradually in
both these directions, so that the connection rod while free to oscillate on a horizontal
axis parallel with the edge or line forming the highest portion of the counter bored
face, cannot oscillate on a vertical axis.
This highest portion of the counter bored face is or may be a portion of an arc

page_text: struck from the centre of the balled out recess that receives the eccentric, that being
the centre of oscillation of the connection rod, and in practice the counter bored
recess is formed by an end mill of just the size to make said recess.
Third. In the automatic tension apparatus of the Willcox and Gibbs machine, a
flat washer covered on one surface with cloth is interposed between the end of the
tension stud and the flat headed screw which forms part of the connection rod. The
purpose of this washer, which is called the "thrust washer" is to deaden the noise
which would be caused by the rapid striking together of the metallic surfaces. In
order to keep the washer always in contact with the end of the metal stud, the washer
was made to fit closely in the hole in the frame in which it works, and the friction of
its cloth covered edge against the sides of the hole was relied upon to keep the washer
from falling away from the stud when the tension rod descended. It has been found
that by constant use the cloth edge became worn, allowing the thrust washer to fall
away from the tension stud at each descent of the rod, and to strike it on the ascent
of the rod, thus producing the noise it was designed to prevent.
According to this part of the present invention the defect above indicated is avoided
by suspending the thrust washer from the tension stud by means of a friction spring
connection. A rigid connection with the tension stud would not answer since it is
necessary to provide for a slight oscillation of the thrust washer on the end of the
tension stud, because of the movement of the tension rod around the centre of the
shaft due to the action of the excentric..
In practice this is accomplished by means of a split spring pin having a ball end,
which pin forms the connection between the thrust washer and tension stud. This
pin may be secured in a hole in the tension stud, and have its split ball end sprung
into a hole in the centre of the thrust washer or as an equivalent construction the pin
may be secured to the washer and have its ball end sprung into a hole in the tension
stud, the lower end of this hole being enlarged to permit the slight oscillation of the
thrust washer..
Another advantage of this construction is that it eliminates the friction of the
thrust washer against the sides of the hole, and prevents any part of the force of
the spring, which retracts the tension stud to clamp the thread, being spent in
overcoming this friction.
Fourth. In order to supply oil to the feed motion and feed eccentric it has been
necessary heretofore either to provide a special oil, hole through the cloth plate
and frame above the eccentric, or to remove the machine from the table. According
to this part of the present invention a transverse oil hole is made from the usual
vertical oil hole by which oil is supplied to the shaft bearing, through the frame to
the surface of the frame adjacent to the feed bar and feed eccentric. This horizontal
hole is parallel with the shaft hole and a little above it, and by this arrangement the
operation of oiling the shaft bearing supplies oil at the same time to the feed bar
and feed eccentric.
Dated this 23rd day of November 1888.
J. H. JOHNSON & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in Sewing Machines.
I JAMES YATE JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this invention (which has been com-
municated to me from abroad by the Willcox & Gibbs Sewing Machine Company of
New York City in the County and State of New York in the United States of
America) 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 sewing machines and particularly to the well known
Willcox & Gibbs machine. in which a chain stitch is produced with a single thread

page_text: :
by the operation of a revolving looper. The improvements constituting the present
invention are as follows.
First. In the operation of the machine it sometimes happens that the downward
motion of the feed bar by the feed eccentric is resisted by the winding up of the
thread upon the looper, or by the accidental catching of the material upon the feed
bar; and the feed motion is thereby injured. To prevent this a shoe is interposed
between the feed eccentric and feed bar, and this shoe is constructed so as ordinarily
to remain in contact with the feed bar; but the parts are so combined and arranged
that in case of accidental interference with the feed motion, as above pointed out,
the feed eccentric and shoe can descend, leaving the feed bar at its highest point.
Injury to the feed mechanism is thereby avoided.
In carrying out the invention, the feed eccentric shoe is kept from revolving with
the eccentric by means of a projection extending into a slot in the feed bar, and the
construction of this slot is such as to permit the shoe to separate from the feed bar
and descend without it. The pressure of a light spring may be used to keep the feed
bar in contact with the upper edge of the shoe in the ordinary operation of the
machine.
In place of a slot or recess in the feed bar for the reception of the projection from
the shoe, a pin driven into the feed bar below the shoe will serve the same
purpose; but the former construction is preferred as presenting more surface for
wear.
Second. In sewing machines of the type specified, motion is communicated to the
needle lever from a ball eccentric on the main shaft through a connecting rod pivotted
at its upper end to said needle lever by means of a ball stud. The connecting rol
consequently has a slight oscillating movement on said ball eccentric. The object of
this improvement is to allow this oscillating movement and at the same time to
"prevent any oscillation of the connecting rod on a vertical axis passing through its
centre from the eccentric to the ball stud. The connecting rod frequently has a
counterbored recess on one side, and in this recess projects a revolving flange or
shoulder carried by the wheel, and as heretofore made a sufficient space has been left
between this flange and the opposite surface, or bottom of the recess to permit the
oscillation of the connecting rod. According to the present invention the bottom of
this recess instead of being a plane surface as heretofore, so that the space between it
and the said flange is of the same width all around, has a portion or horizontal edge
touching or nearly touching the said flange on each side of the eccentric,
this portion being on a transverse or horizontal line passing centrally across the
recess. From this line or edge the counterbored face of the recess is cut away from
the shoulder or flange both upward and downward, forming a space between said face
and flange which widens gradually in both these directions, so that the connecting
rod, while free to oscillate on a horizontal axis parallel with the edge. or. line
forining the highest portion of the counterbored face, cannot oscillate on a vertical
axis.
This highest portion of the counterbored face is or may be a portion of an arc
struck from the centre of the balled out recess that receives the eccentric, that being
the centre of oscillation of the connecting rod, and in practice the counterbored recess
is formed by the end mill of just the size to make said recess.
The improvement may of course be applied to connecting rods not having a
counterbored recess. In such case the raised portion or edge will be formed on the
face of the connecting rod so as to touch or almost touch a stationary surface, or
running collar, whichever may be adjacent to the connecting rod, thus permitting the
rod to oscillate on an axis parallel with the raised edge, but not in any other
direction.
Third. In the automatic tension apparatus of the Willcox and Gibbs machine, a
flat washer covered on one surface with cloth, is interposed between the end of the
tension stud and the flat headed screw which forms part of the connecting rod. The
"purpose of this washer, which is called the "thrust washer" is to deaden. the noise
which would be caused by the rapid striking together of the metallic surfaces. In

page_text: order to keep the washer always in contact with the end of the metal stud, the washer
was made to fit closely in the hole in the frame in which it works, and the friction
of its cloth covered edge against the sides of the hole was relied upon to keep the
washer from falling away from the stud when the tension rod descended. It has
been found that by constant use the cloth edge became worn, allowing the thrust
washer to fall away from the tension stud at each descent of the rod, and to strike it
on the ascent of the rod, thus producing the noise it was designed to prevent.
According to this part of the present invention the defect above indicated is
avoided by suspending the thrust washer from the tension stud by means of a
friction spring connection. A rigid connection with the tension stud would not
answer since it is necessary to provide for a slight oscillation of the thrust washer
on the end of the tension stud, because of the movement of the tension rod around
the centre of the shaft due to the action of the eccentric.
In practice this is accomplished by means of a split spring pin having a ball end,
which pin forms the connection between the thrust washer and tension stud. This
Din may be secured in a hole in the tension stud, and have its split ball end sprung
anto a hole in the centre of the thrust washer; or as an equivalent construction,
the pin may be secured to the washer and have its ball-end sprung into a hole
in the tension stud, the lower end of this hole being enlarged to permit the slight
oscillation of the thrust washer.
Another advantage of this construction is that it eliminates the friction of the
thrust washer against the sides of the hole, and prevents any part of the force of the
spring, which retracts the tension stud to clamp the thread, being spent in overcoming
this friction.
In the accompanying drawings which form part of this specification, Figures I, II-
and III illustrate the improvement in the feed mechanism, Figures. IV-VIII, the
improvement in connecting rod, and Figures IX-XI the improvement in tension
apparatus.
The machine partially iBustrated in these drawings is the well known Willcox and
Gibbs Single Thread Chain Stitch Machine.
Figure I is a partial plan view of the parts under the cloth plate of the machine;
Figure II a side elevation, and Figure III a rear. view of the feed bar and
shoe.
A is the main shaft, and a the feed eccentric, which imparts the usual four motions
to the feed bar B. Between the feed bar B and eccentric a is interposed the shoe C,
surrounding the eccentric and having a flat upper surface, upon which the feed bar
rests by gravity. The contact of these parts in the normal working of the machine
is further insured by the pressure of the spring d. Shoe C has a projection or tail-
piece c which extends between the overhanging part e and the projection fat the rear
of the feed bar, these parts forming between them a recess or slot. Contact of the.
projections e and f with the tail-piece e prevents rotation of the shoe C with eccentric a.
At its narrowest part the recess or slot is about the width of the tail-piece c; but this
part is simply a line from which the recess or slot is widened in both directions by
cutting away the projections e and f at an angle, as best shown in Figure III.
The manner in which the part fis cut away forms an edge g upon which as a centre-
the shoe C can turn in case anything occurs to arrest the descent of the feed bar. The
separation of the shoe C and feed bar B is shown in Figure III.
It will readily be seen that the construction described permits the feed.eccentric to
move to its lowest point without necessitating the descent of the feed bar, and at the
same time causing no damage to the parts.
Figure IV of the accompanying drawings is an elevation partly in section, of a
portion of a sewing machine illustrating the improved construction of the connecting
rod; Figure V is a horizontal section of the wheel and connecting rod, and
Figures VI, VII, and VIII are detail views of a part of the connecting rod.
In these figures A represents the main shaft; a the ball eccentric thereon; B the
wheel; C the connecting rod; D the needle lever, and d the ball-stud connecting the
connecting rod with the needle lever.
זי,

page_text: -The wheel B has a flange b, which projects into a counterbored recess c in the
opposing face of the connecting rod. The inner vertical face of recess c, instead
of being a plane surface as heretofore, is inclined away from the flange b both upward
and downward from a horizontal line or edge e on each side of the eccentric. This
edge or line touches or nearly touches the rotating flange band is parallel with the
axis on which the connecting rod oscillates; but the contact of the edge e with the
flange on both sides of the recess prevents any vibration or oscillation of the said
connecting rod on a vertical axis.
In practice the highest portion of the edge e may be a portion of an arc struck
from the centre of the balled out recess, as indicated in Figure VIII, this point being
in the axis upon which the rod Coscillates, and the recess is conveniently formed by
means of an end mill of the proper size.
It will of course be understood that the invention is not limited to the precise
machine or construction shown, which is illustrated merely by way of example.
Figure IX of the drawings is a rear view of the machine partly in section, Figure ✗
a sectional view of the tension apparatus on a larger scale, and Figure XI a detail
illustrating a modification.
In these figures A represents the main shaft; a the tension eccentric; B the tension
rod; the flat-headed screw for actuating the tension stud c; C the spring for
returning the tension stud, and d the thrust washer.
g
The thrust washer d is covered on its lower face by a piece e of cloth or sound
deadening material, held in place by a binding wire f which lies in the grooved edge
of the washer. The washer is held in position against the lower end of tension stud c
by means of the split-ball-ended-friction pin g. As shown in Figure X pin is
inserted and held securely in a hole in stud c, the hole being slightly enlarged at its
lower portion to permit the expansion of the ball end of the pin, which is sprung
into the hole bored centrally in the thrust washer d. The pressure of the split
ends h against the sides of this hole is sufficient to hold the washer..in place against
the end of the stud, while allowing it the slight oscillation requ red.
As shown in Figure XI, the pin g is rivetted firmly to the thrust washer, and its
split ball-end his inserted in a hole bored in the tension stud, holding the washer up
by frictional contact with the sides of the hole.. This hole is enlarged. at its lower
portion as shown, leaving a space around the pin sufficiently large to permit the slight
oscillation required.
Another advantage attending this improvement is that it eliminates the friction of
the thrust washer against the sides of the hole in which it works, so that the force of
spring C, which retracts the tension stud and clamps the thread is not in any
degree spent in overcoming such friction. Figure IX shows the thrust washer made
slightly smaller in diameter than the hole in the frame, so that it does not touch the
sides thereof.
Modifications may obviously be made in the details of construction without departing
from the spirit of the invention.
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 :-
1. The combination with the feed bar and eccentric of a shoe surrounding said
eccentric and communicating motion therefrom to said feed bar, said shoe having a
tail-piece or extension resting upon a projection of said feed bar, upon which it can
rock sufficiently to permit the descent of said eccentric and shoe, leaving said feed
bar in the highest position, substantially as described.
2. The combination of the feed bar, the feed eccentric and the shoe interposed
between the two and having a tail-piece projecting into a recess or slot in said feed
bar, said recess or slot having a contracted portion about the width of said tail-piece,
and having divergent walls on each side of said contracted portion, substantially as
and for the purpose set forth.

page_text: 3. The combination of a shaft, a ball eccentric thereon, a connecting rod mounted
on said eccentric and adapted to convey motion to a vibratory part, and a part such
as a flange having a surface adjacent to said connecting rod, the latter being provided
with a raised portion or edge on each side of the eccentric touching or nearly touching
said adjacent part, and being cut away from the surface of said part on both sides of
said raised portion or edge, so that said rod can oscillate on said eccentric on an axis
parallel with said edge, but is prevented from oscillating in any other direction,
substantially as described.
4. The combination of the shaft, ball eccentric, vibrating lever, connecting rod for
communicating motion from said eccentric to said lever and provided with an annular
counterbored recess on one face, and a wheel on said shaft having a flange extending
into said recess, the face of said recess adjacent to said flange being formed with a
raised portion or edge touching or nearly touching said flange, and being cut away
from the latter at an angle, so that the connecting rod can oscillate on an axis parallel
to.said raised portion or edge, but is prevented from oscillating on an axis perpendicular
thereto, substantially as described.
5. In a tension apparatus, the combination with the tension stud and tension rod
for actuating the same, of the thrust washer interposed between the two and
suspended from the tension stud by a frictional spring connection, substantially as
described.
6. The combination with the tension stud and tension rod for actuating the same, of
the thrust washer suspended from the tension stud by a spring friction pin, substan-
tially as described.
7. The combination with the tension stud and actuating tension rod, of the thrust.
washer suspended from the former by a ball-ended-split friction pin, having its split
ball end expanded in a hole in said washer, substantially as described.
Dated this 26th day of June 1889:
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, W.C., Agents.