IMPROVEMENTS IN SEWING MACHINES
Year: 1872

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Gentleman, for the Invention of
"IMPROVEMENTS IN SEWING MACHINES."-A communication from
abroad by the Wilson Sewing Machine Company, of Cleveland,
in the State of Ohio, United States of America.
Scaled the 26th November 1872, and dated the 15th August 1872.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition,
on the 15th August 1872.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN SEWING MACHINES," a communication to
me from abroad by the Wilson Sewing Machine Company, of Cleveland,
in the State of Ohio, United States of America, to be as follows:-
-
This Invention consists of certain improvements in the tension, take-
up, needlo bar bearing, feed mechanism, shuttle race, ways for the shuttle
driver slide, and mechanism for driving the needle arm.

page_text: The improvement in the tension relates to the pressure spring. In
lieu of using a spiral, volute, or other ordinary form of spring, I employ
a disc made of spring metal with a hole in its centre for the passage of
the screw stem of the tension, and with long spring fingers formed by
cutting in the disc eccentric slits or slots extending from the exterior
of the disc towards the central hole. These fingers are bent down so
that when the spring is in place their tips will rest on the tension.
The form of these fingers may be somewhat varied, but they should
all start from near the central opening, and then follow a curved path
so as to obtain considerable length in order to have the necessary
spring action without making the device too large. They should also
preferably taper towards their outer ends. The adjusting nut bears
upon the spring at a point within the compass of the spring fingers,
consequently the latter, at the points where they bear upon the tension,
are enabled to operate equally and to the best advantage. I prefer to
interpose a cloth, rubber, or other suitable washer between the spring
and the tension sheave or plate, although the washer is not indes-
pensable.
The improvement in the take-up consists principally in the in-
strumentalitics for holding and adjusting it in order to take up more
or less slack thread as required for thin or thick goods. These parts
arc chiefly enclosed within the head of the machine, the only parts
projecting being the head of the take-up lever, and the adjusting and
holding nut. The take-up lever consists of an angle or bell-crank lever,
the longer arm of which, provided at the end with a thread eye, partly
projects from the side of the head, and is arranged to work up and down
in a vertical slot formed in the same. The shorter arm of the lever is
connected with the reciprocating needle bar by a link, by means of
which connection the proper movements of the take-up at the proper
times are imparted from the needle bar. The take-up lever at its
angle is pivoted to a block, the face of which is held tightly against
the inner face of the side of the head by means of a nut screwing
from the outside of the head on to a stem attached to the block and
projecting through the head. To allow the adjustment of the take-up
so as to adapt it to draw up more or less thread as desired, a vertical
slot is formed in the head through which the stem passes, and the block
can, by loosening a nut, be adjusted up or down to any point within the
limits determined by the length of the slot, and can there be held by

page_text: tightening up the nut. Raising the block increases the length of
movement of the take-up, lowering it decreases the range of move-
ment.
. The needle bar plays up and down through spirally slotted bushings
at the top and bottom of the head. These bushings which are re-
moveable and adjustable are inserted in cylindrical openings in the
head, and are combined with set screws in the face plate of the head
which are arranged to have their points in contact with the bushings.
Slots, which split or divide the bushings on one side, extend from the
top to the bottom of the same, and instead of being vertical are inclined
or pursue a spiral course partly around the bushing. The object of the
bushings is to prevent the needle bar from wearing the hole in the head
through which it passes, and owing to the slots if cither the needle bar
or the bushings wear the screws can be set up so as to compress the
bushings bringing the edges of the slots closer together, and thus tighten™
the bushings so as to take up all wear.
The feed mechanism is greatly simplified, and is composed of as few
parts as possible. It consists of a feed bar to which a feed surface is
attached. This bar is held to the under-side of the cloth plate by a
yoke or strap at one end, while the feed surface at the other end is in a
recess formed for it in the top of the cloth plate. A spring is employed
to give the back and down motions to the feed. An adjusting screw
on the end of the feed bar serves to regulate the extent to which the
spring shall rétract the bar, thus determining the length of feed. "The
up movement of the feed, to project the feed surface above the cloth
plate, is caused by a rod which is connected by a strap with an eccentric
on the driving shaft, and has its other end supported in a rocker bearing
through which it freely slides. When the most eccentric portion of the
eccentric is above the shaft in the position it occupies when the feed is
just about to move forward, the connecting rod will be drawn up
towards the cloth plate so as to press upward on the feed bar and force
the feed surface above the cloth. This pressure of the rod upon the bar
continues until the feed has taken place, at which time the most
cccentric portion of the eccentric begins to come below the shaft, and
the rod is consequently lowered so as to permit the spring to draw
down the feed surface. The forward movement of the feed is effected
by a link jointed to a sleeve fixed on the connecting rod (which sleeve
is the part of the rod that bears on the feed bar to move it upward), and

page_text: provided at its other end with a slot in which is received a pin on the
feed bar. The forward movement of the rod will cause the link to
advance, and the end of the slot nearest the connecting rod is brought
sooner or later in contact with the pin, according to the adjustment of
the regulating nut. If the nut is adjusted for a long feed the link
operates upon the pin sooner than it would in case the adjustment were
for a short feed.
In lieu of casting the shuttle race and of permanently uniting it with
the under side of the cloth plate, I strike it up out of metal with a
flange to attach it to the cloth plate, a concave portion to receive the
shuttle and shuttle driver and a slot, so that it may be always kept
free of dirt and refuse, which can escape at once through the slot. The
holes through which the holding screws pass are clongated, so as to
permit the adjustment lengthwise of the race whenever desired. The
race is set against the side of one of the two ways in which the shuttle
driver slide moves, and is there held by means of screws which pass
through the flange into the cloth plate. The shuttle driver slide is
connected with an arm on the crank pin of the driving shaft by a
connecting rod.
Of the two ways or grooved pieces between which the shuttle driver
slide moves, the outer one is removeable and adjustable nearer to or
further from the other; this being effected by providing it with cars
slotted transversely to the length of the piece through which holding
screws pass into the cloth plate. By reason of this arrangement one
piece can be set up towards the other so as to take up all wear and
cause the slide to move evenly and without noise or lateral movement,
whilst it admits also of the parts being taken apart to clean this portion
of the machine with greater facility.
The mechanism for driving the needle arm consists of a crank pin
fixed on a disc attached to the driving shaft, also a heart-shaped cam
formed in the lower end of the vertical portion of the bell-crank lever
needle arm, which arm is pivoted at its angle to the standard of the
machine. The descent of the needle is effected during that portion
of the movement when the crank pin is passing through the lower
portion of the cam slot. The advantage of this arrangement, which
is the reverse of that employed in machines of this kind now generally
used, is that the descent of the needle to pierce the cloth takes place
at a time when the operative length of the vertical arm of the lever

page_text: is continually increasing, so that the descent is slower and more gradual,
and more power is obtained than would be the case were the shaft or
crank to revolve in an opposite direction, and consequently the needle
to descend when the operative length of the vertical arm of lever was
continually decreasing, for this would cause a more rapid but pro-
portionately less powerful descent. On the contrary this quick but
less powerful movement of the needle arm is now imparted to it.
under my arrangement in order to raise the needle out of and above
the cloth, as the crank at this time will move through the upper
portion of the heart-shaped cam slot, and I therefore by this reversal
of the movement adapt the varied movements of the needle arm to the.
real requirements of sewing, forcing the needle into and through the
cloth more slowly but with more power than in raising it from the-
cloth. This arrangement of the mechanism requires the shuttle to be
pointed outward or away from the driving shaft instead of towards it,
as las heretofore been the practicè..
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 6th February 1873.
TO ALL TO WHOM. THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County: of
Middlesex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of August, in the year of
our Lord. One thousand eight hundred and seventy-two, in the thirty-
sixtli year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John Henry Johnson, Her special license.
that I, the said John Henry Johnson, my executors, administrators, and
assigns, or such others as I, the said John Henry Johnson, my executors,
administrators, or assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention-for "IMPROVEMENTS IN SEWING
"MACHINES," a communication to me from abroad by the Wilson Sewing

page_text: are bent down so that when the spring is in place their tips will rest on
the tension as shown in Figure 5. The form of these fingers may be
somewhat varied, but as seen in the Drawing they should all start from
near the central opening a, and then follow a curved path so as to obtain
considerable length in order to have the necessary spring action without
making the device too large. They should also preferably taper towards.
their outer ends; a spring thus made possesses considerable advantages;
it is very compact and admits of the pressure being evenly applied. As
the adjusting nut & bears upon the spring at a point within the compass
of the spring fingers, the latter at the points where they bear upon the
tension are enabled to operate equally and to the best advantage. I.
prefer to interpose a cloth rubber or other suitable washer e between the
spring and the tension shcave or plate, although this washer is not
indispensable.
The improvement in the take-up consists principally in the instru-.
mentalitics for holding and adjusting it in order to take up more
or less slack thread as required for thin or thick goods. The
devices are shewn clearly in Figures 1 and 5; they are for the greater
part enclosed within the head B of the machine, the only parts
projecting being the end of the take-up lever and the adjusting and
holding nut. The take-up lever consists of an angle or bell-crank
lever C, the longer arm of which provided at the end with a thread eye,
partly projects from the side of the head and is arranged to work up and
down in a vertical slot formed in the same. The shorter arm of the
lever is connected with the reciprocating needle bar D by a link by
means of which connection the proper movements of the take-up at the
proper times are imparted from the needle bar. The take-up lever at
its angle is pivoted to a block g, the face of which is held tightly against
the inner face of the side of the head B by means of a nut / screwing
from the outside of the head on to a stem i attached to the block, and
projecting through the head. To allow the adjustment of the 'take-up so
as to-adapt it to draw up more or less thread as desired a vertical slot j is
formed in the head B, through which the stem i passés, and the block g
can by loosening the nut h be adjusted up or down to any point within
the limits determined by the length of the slot, and can there be held by
tightening up the nut. Raising the block increases the length of move-
ment of the take-up, lowering it decreases the range of movement. This
arrangement is compact and simple, all the parts of the take-up
excepting only those actually required to be exposed aro-concealed, and

page_text: the same device serves not only to support and hold, but also to adjust
the take-up lever.
The needle bar D plays up and down through spirally slotted
bushings at the top and bottom of the head B. These bushings
which are removeable and adjustable are inserted in cylindrical open-
ings in the head, and are combined with set screws k¹ in the face
plate of the head which are arranged to have their points in contact
with the bushings. The slots which split or divide the bushings on
one side, extend from the top to the bottom of the same, and instead of
being vertical are inclined, or pursue a spiral course partly around the
bushing. The object of the bushings is to prevent the needle bar from
wearing the hole in the head through which it passes, and owing to the
slots k, if either the needle bar or the bushings wear the screws k¹ can
be set up so as to compress the bushings, bringing the edges of the slots
closer together, and thus tighten the bushings, so as to take up all
wear.
The advantage gained in making the slots of the bushings spiral instead
of straight is, that in case a straight-up and slot is employed the edges of
the slot will wear the needle bar so that a part of the bar will-project
between the edge of the slot, thus rendering the bushing useless as it
cannot be further tightened up. The spiral slot obviates this difficulty.
It has been the object of the Inventor in the feed mechanism to
simplify it, and to employ as few parts as possible. It consists of a feed
bar 1, to which the feed surface is attached. The arrangement of this
bar is shown in Figure 7. It is held to the under side of the cloth plate
by a yoke or strap & at one end, while the feed surface at the other end
is in a recess formed for it in the top of the cloth plate. A spring m is
employed to give the back and down motions to the feed. An adjusting
screw on the end of the feed bar serves to regulate the extent to which
the spring shall retract the bar, thus determining the length of feed.
The up movement of the feed to project the feed surface above the cloth
plate is caused by the rod E which is connected by a strap with the
cccentric F on the driving shaft G, and has its other end supported in a
rocker bearing H through which it freely slides. The eccentric revolves
in the direction indicated by the arrow in Figure 6, and when its most
eccentric portion is above the shaft in the position it occupies when the
feed is just about to move forward the connecting rod E will be drawn
up toward the cloth plate so as to press upward on the feed bar and force

page_text: the feed surface above the cloth. This pressure of the rod upon the bar
continues until the feed has taken place, at which time the most
eccentric portion of the eccentric begins to come below the shaft G, and
the rod E is consequently lowered so as to permit the spring m to draw
down the feed surface. The forward movement of the feed is effected
by a link I jointed to a sleeve I', fixed on the connecting rod (which
sleeve is the part of the rod that bears on the feed bar to move it
upward), and provided at its other end with a slot p, in which is
received a pin o on the feed bar. The forward movement of the rod E.
will cause the link to advance, and the end of the slot p nearest the
connecting rod is brought sooner or later in contact with the pin o, .
according to the adjustment of the nut n. If the nut is adjusted for a
long feed the link operates upon the pin sooner than it would in case.
the adjustment were for a short feed.
In lieu of casting the shuttle race and of permanently uniting it with
the under side of the cloth plate I strike it ap out of metal, as shown
at J, Figure 3, with a flanger to attach it to the cloth plate, a concave S
portion to receive the shuttle and shuttle driver, and a slot & so that it
may be always kept free of dirt and refuse, which can escape at once
through the slot. The holes through which the holding screws s' pass
are elongated so as to permit the adjustment lengthwise of the race
whenever desired. The race is set against the side of one of the two.
ways K in which the shuttle driver slide moves, and is there held by
means of the screws &¹ which pass through the flanger into the cloth
plate. The shuttle is shown at ; the shuttle driver at v', and also
separately in Figure 4; and the shuttle driver slide at v³. This slide is
connected with an arm wo³ on the crank pin w of the shaft G by a con-
necting rod w².

page_text: The mechanism for driving the needle arm consists of the crank pin w
fixed on a disc y attached to the driving shaft G, and the licart-shaped
cam formed in the lower end of the vertical portion of the bell crank
lever needle arm O, which arm is pivoted at its angle P to the standard
of the machine.
The crank moves in the direction of the arrow, and the arrangement
of parts is such that the descent of the needle is effected during that
portion of the movement when the crank pin is passing from the point =¹
through the lower portion of the cam slot. The advantage of this
arrangement, which is the reverse of that employed in machines of this
kind now generally used, is that the descent of the needle to pierce the
cloth takes place at a time when the operative length of the vertical arm
of the lever O is continually increasing, so that the descent is slower
and more gradual, and more power is obtained than would be the case
were the shaft or crank to revolve in an opposite direction, and con-
sequently the needle to descend when the operative length of the
vertical arm of lever O was continually decreasing, for this would cause
a more rapid but proportionately less powerful descent. On the contrary,
this quick but less powerful movement of the needle arm is now imparted
to it under my arrangement in order to raise the needle out of and
above the cloth, as the crank at this time will move through the upper
portion of the heart-shaped cam slot; and I therefore by this reversal
of the movement adapt the varied movements of the needle arm to the
real requirements of sewing, forcing the needle into and through the
cloth more slowly but with more power than in raising it from the
cloth.
This arrangement of the mechanism requires the shuttle v to be pointed
outwards or away from the driving shaft G, instead of towards it as has
heretofore been the practice in the machine (the Wilson Sewing Machine)
to which these improvements are represented as applied.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured to
me by the herein-before in part recited Letters Patent is,-
First. A spring for sewing machine tensions consisting of a disc with
eccentrically curved and downwardly bent spring fingers, the whole being
constructed substantially as specified.

page_text: Second. In combination with the take-up operated from the needle
bar, substantially as described, the holding block to which the said
lever is pivoted, when the said block is adjustable to regulate the.
action of the take-up, substantially as shewn and set forth.
Third. In combination with the needle bar and head in which the
same is held the spirally slotted bushings and set screws for holding and.
tightening the same, substantially as shewn and described.
.
Fourth. The slotted link intermediate between and connected and
operating in conjunction with the feed bar and reciprocating rod E, as -
shewn and set forth.
Fifth. The peculiar feed mechanism constructed and arranged to
operate as herein shown and set forth.
Sixth. The shuttle race struck up from metal; and formed and attached.
to the machine, as shewn and set forth.
Seventh. Operating the needle arm through the medium of a heart-
shaped cam groove or slot and a crank pin in such a manner that. the
descent of the needle arm shall take place when the crank pin traverses
the lower portion of the slot, as and for the purposes set forth.
Eighth. In combination with the needle arm its heart-shaped cam
groove or slot and the crank pin, arranged and operating as above
specified, an outwardly pointed shuttle arranged and operated sub-
stantially as shewn and set forth.
•
D
In witness whereof, I, the said John Henry Johnson, have to this
my Specification "set my hand and seal, this Sixth day of
February One thousand eight hundred and seventy-three.
a
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