IMPROVEMENTS IN SEWING MACHINES
Year: 1882

page_text: LETTERS PATENT to Sydney Pitt of Sutton in the County of Surrey for
"
an Invention of "IMPROVEMENTS IN SEWING MACHINES Communicated to
him from abroad by Lebbeus Baldwin Miller and Philip Diehl of Elizabeth
in the County of Union and State of New Jersey United States of America
COMPLETE SPECIFICATION filed by the said Sydney Pitt at the Office of
the Commissioners of Patents on the 24th October 1882.
"
SYDNEY PITT of Sutton in the County of Surrey.
"IMPROVEMENTS IN SEWING
MACHINES Communicated to me from abroad by Lebbeus Baldwin Miller and
Philip Diehl of Elizabeth in the County of Union and State of New Jersey
United States of America.
This Invention has reference primarily to the feeding and shuttle driving
mechanism and the presser bar shuttle and tension mechanism of sewing machines
and it consists of certain constructions and combinations of mechanical devices
which are set forth in detail in claims at the close of this Specification.
All of the said features of invention need not be embodied in the same machine
but in order that the invention may be fully understood I have represented in
the accompanying Drawings and will proceed to describe some of the principal
parts of a sewing machine embodying all of the said features in the best form in
which they have been embodied at the present date.
In the said Drawings Figure 1 represents a side view of such sewing machine
with the side plate of the bracket arm removed, Figure 2 is a view of the face of
the bracket arm and of portion of the feed and shuttle mechanism and illustrates
more especially the method of driving the feed, Figure 3 is a view of the underside
of the machine shewing the shuttle driving mechanism and feed mechanism from
beneath. Figure 4 is a detached view of the feed wheel with the mechanism
employed to drive and control it. Figures 5 to 18 inclusive shew parts of the
machine detached from the residue, and Figures 19 and 20 illustrate a novel
feature in the shuttle driving mechanism.
The general form of the said sewing machine does not differ materially from
many sewing machines in common use, It has a bed plate A Figures 12 and 3
with which the other parts are connected-a bracket arm B Figure 1 to support

page_text: upon which the
the needle and presser bars above that portion of the bed plate
material to be sewn will rest a main driving shaft C'extending through the
bracket arm B to drive the needle bar which is arranged to slide up and down
through the head of said bracket arm and also by means of a crank connection
and rock and oscillating shafts to oscillate the shuttle driver which carries the
shuttle.
The general manner of interlocking the needle and shuttle threads to form the
stitch and the manner of carrying the shuttle are the same as described in the
Specifications of Patents granted to me N° 2813 in the year 1878 and Nº 3079 in
the year 1879.
In these previous Patents however the feed shewn and described belongs to the
class commonly known as "four motion" in which the feeding surface during its
retreating movement is not in operative contact with the material being sewn.
The present invention being adapted more especially for those kinds of work
which require that the feed should remain continuously and firmly in contact
with the goods belong to the class commonly known as "wheel feed." Motion
is given to the feed from the main shaft of the machine by means of an eccentric ‹.
Figures 1 and 4 on the main driving shaft C of the machine. The eccentric
operating through the forked connecting piece J gives motion to the horizontal
feed rock shaft F through the arm 'e, the arms eat the other end of said feed
rock shaft F being pivoted to the link K (Figures 1 3 and 4) the other end of
which link is hinged to the driving ring D at the point b. Figure 4. The amount
- of to and fro movement given by the eccentric to the link K can be adjusted in the
following manner. The upper end of the connecting piece J is jointed to one end
of a link J, the opposite end of this link is jointed to a lever arm Jª which can
be turned on a fixed fulcrum at Js the other arm of the lever passes through a
slot in the frame of the machine and can be clamped thereto as shewn by a clamp
nut. By setting this end of the lever either higher or lower the link J', can be
brought into positions more or less inclined to the connecting piece J. As the
upper end of the piece J is oscillated to and fro horizontally by the eccentric it
will also be made to rise and fall being controlled by the link J and the amount
of such upward and downward movement will depend upon the inclination of the
link J¹.
The feed proper consists of the feed wheel constructed in the form of a ring with
serrated teeth on its periphery arranged to project through a slot in the table in
the usual manner as shewn at Figure 2. This wheel or ring is supported in a
frame N which frame is binged at the point E to the table of the machine and
is provided with lugs n n. through which the adjusting screw n' and the screw n²
are passed. As the frame is hinged only at E to the bed of the machine, its natural
tendency would be to drop downward away from the said bed, but it is prevented
from doing this and sustained in its proper position by the bearing of the point
of the adjusting screw n. against the flange of the bed plate at a. The hinge at E
is thus made to serve as a fulcrum point and by turning the said screw n'. one
way or the other the frame can be raised or lowered carrying with it the feed
surface and the elevation of the said operative portion of said surface above the
level of the bed-plate can thus be regulated at will. The function of the screw n²
which can be adjusted to correspond with each adjustment of the screw n¹ is
simply by bearing against the other flange of the bed plate to keep the frame solid
and steady and prevent vibration.
The necessary intermittent rotating motion is communicated to the feed ring or
wheel in the following manner. The link K receiving as above explained
through the aring el. el. of the feed rock shaft F a regular reciprocating motion is
hinged at b to the driving ring D which consequently is made to turn in the
frame with a nearly circular reciprocating motion of corresponding extent. The
face of this driving ring D is provided with two lugs b'. b. arranged to project
one on either side of (or in other words straddle) a flange o which projects from
the inside face of the feed wheel O. Said driving ring D. is also supported and

page_text: guided by the screw b. acting in the slot bit is also acted upon by the spring b
- one end of which is attached to the frame N. When the stitch is being formed
and the feed should rest the said driving link K is moving from left to right
the spring b' also acts to turn the ring in the same direction as it is being turned
by the link and it will consequently cause said driving ring to move in a line so
nearly corresponding with the line of the flange o. that its lugs b'. b. will not grip
said flange and its motion will not be communicated to the feed wheel O. But on
the return movement of the arms e'. e'. when the feed should move, the link K
acts in a direction against the said spring b. and the ring is consequently drawn
by the link into a position slightly eccentric to the flange o-therely bringing both
said lugs into firm contact with said flange cramping and holding it between them
and then communicates n " circular
» motion to said wheel. As the time and
extent of the motion will depend on and be governed by said movements of the
feed rock shaft the forward movement of the feed and the extent to which the
goods are to be carried between each stitch will therefore depend upon the extent
to which the shaft is rocked and this is controlled in the manner above
described.
In order to permit the point of the shuttle to enter and hold the loop of the
needle thread until the eye of the needle rises above the fabric, and afterwards to
draw down sufficient thread to pass over the shuttle body the shuttle requires to
have an oscillating movement through more than half a circle.
In the former Patent N° 3079 in the year 1879 this motion was obtained from
a crank on the main driving shaft through a connection, the other end of which
was pivoted to one arm of a rock shaft. Said rock shaft was provided with
another arm which was slotted to receive a roller placed on the outer end of a
crank on one end of a parallel oscillating shaft, the other end of which carried the
shuttle. In this new machine the same form of crank with main driving shaft
and a similar connection c pivoted to the arm of the rock shaft S. sce Figures 19
and 20 are used, but instead of the slotted arm receiving the crank roller of the
oscillating shaft an arm 8. is used to the outer end of which is pivotted the link V
and the other end of said link V is pivotted to the outer end of the crank t. on the
ond of the shuttle oscillating shaft T.
By the revolution of the crank on the main shaft a regular reciprocating or
rocking motion is communicated by means of the connection c to the arm s'. of the
rock shaft S. and consequently the arm s, on the said rock shaft. The oscillating
shaft T being parallel to said rock shaft S, and its crank t. being positively
connected by the link V to the arm s, by varying the relative lengths of the arm s
and crank t, the extent of the oscillating motion communicated to the shaft T can
be increased or diminished. In the present instance it is desired to communicate
to the shaft T an oscillating motion of greater extent than that communicated to
the rock shaft S. and to make its oscillating movement more than a half circle and
therefore the arm s. is mado relatively longer than the distance between the centre
of the shafts S and T. and the arm t shorter than the arm 8. By this means from
a comparatively small rocking motion of the shaft S, I impart to the shaft T the
desired oscillating motion in excess of a half circle.
The shuttle oscillates in a race in a manner similar to that described in the
Specification of the before mentioned Patents but instead of making the ring Q
which forms the body of the race solid as therein described a spring back q is
used which is fastened to the lower part of the ring Q by the two screws q'. q'.
leaving the top portion of said ring free to yield to any extraordinary pressure
although firm enough to keep the shuttle in position under ordinary circumstances.
In my former Specification N° 3141 in the year 1880 I described a shuttle
constructed in two portions hinged together and forming a box to contain
the thread.
According to the present invention such portions are held together and the
tension on the shuttle thread is obtained by the following devices.
In Figures 1 to 4 some of the improvements are shewn applied to a shuttle in

page_text: which the planes of the circle described by the thread on the bobbin as it lies in
the shuttle are at right angles or nearly so to the plane of motion of the shuttle
so that as the thread is drawn off from the bobbin the bobbin shall revolve in a
direction at right angles to the shuttle's motion so that the shuttle's motion cannot
affect the unwinding of thread from the bobbin. The form of shuttle shown at
Figures 1. to 4 is especially adapted for manufacturing work.
In Figures 5. 6. 7 8 and 9 some of the improvements are applied to a shuttle in
which the bobbin is in the same position in the shuttle as shewn in the Drawings
annexed to the former Specification
I will first describe the improvements which are shewn at Figures 1 to 4 of the 1
Drawings.
To the larger portion of the shuttle which is distinguished by the letter X is
rigidly attached at a point nearly opposite and furthest from the hinge a spring X¹
the free end of which bears and presses on a lug projecting from the smaller
portion . at a point in rear of the hinge pivot. The hinge pivot is thus made a 1
fulcrum point and the pressure beyond it forces the opposite sides of the larger
and smaller portions together closing and securing the box and also giving an
elastic tension upon the free end of the thread which is drawn out as shewn in
Figures 14 and 15 between the rim or edge surfaces of the two portions of said
shuttle. This spring X is inade strong enough to give the greatest amount of 2
tension required in practice. In order to decrease the amount of tension and
regulate it as required a lighter spring is applied in addition which tends to forco
asunder the two portions of the box and the tension on the thread is adjusted by
adjusting the strength of this lighter spring.
In Figures 14 and 15 this is shewn to be effected by the portion of the shuttle
being provided with a set screw y fitting in a hole tapped to receive it When the
two portions are brought together the lower end of this screw enters a hole in the
other portion X of the shuttle in which hole is placed a small spring or some
elastic substance. By turning this screw to the right a counter-pressure of limited
extent is exerted tending to force the adjacent surfaces of the portions apart a
sufficiently to relieve the pressure on the free end of the thread to the desired
extent although they are still held in position to keep the bobbin securely in the
shuttle by the action of the spring X.
A flat spring similar to that shown in Figures 16 17 and 18 might be used
instead of the small spring or elastic substance in a hole as shewn at Figures 12
13. 14 and 15 and the strength of the spring may be either adjusted as shown at
Figures 16. 17 and 18 or the spring may be made to act against the end of an
adjustable set screw as above explained.
In place also of nipping the thread between the rigid surfaces of the two parts
of the shuttle one or other part might be made to carry a spring to bear against
the thread and press it up to the rigid surface of the other part. In this case the
strength of the spring may be regulated by a set screw as shown at Figures 16. 17.
and 18.
In these Figures X a. are the two portions of the shuttle hinged together X' is
the spring by which the two parts are held closed together. Z is the spring which
bears upon the thread and puts tension upon it. Z is a set screw by which the
spring Z can be set to stand outwards more or less from the portion of the shuttle
which carries it and so cause the spring to bear more or less upon the thread when
the two parts of the shuttle are closed together. To prevent the bobbin from
rattling between the two parts of the shuttle a light spring X is secured to the
clasp spring X and made to bear against one side of the bobbin as shewn at
Figures 16, 17 and 18.
As the machine is constructed to use what is generally known as a positive
thread take up it is necessary in order to produce the best results that the needlo
thread should become slack when the eye of the needle in its descent reaches the
surface of the goods to be sewn and not before. This is accomplished by the
device shewn which is an adjustable slack thread controller consisting of the coil

page_text: spring W having its free end looped to receive the thread and its other end firmly
attached to the face plate by the tension stud, the collar w. the receptacle for
said spring and collar and the set screw w¹. said coil spring is contained in a
receptacle and its free end projects through an opening made sufficiently wide
to allow the greatest amount of motion required. Around this spring and within
the receptacle is placed the moveable collar w having an opening of corresponding
extent through which the free end of the spring W must also pass and being held
firmly in the required position by tightening the set screw w' which is tapped into
it and which moves in the necessary direction through a slot in the receptacle w³.
When it is necessary to decrease the extent of motion of the spring W for the
purpose of slackening the thread more quickly or when the eye of the needle is in
a higher position as in sewing thick goods the moveable collar is turned to the
left and set and the space through which the free end of the spring can move
diminished to the desired extent. To increase the extent of motion and delay the
slackening of the thread the collar is set to the right.
It is expressly desirable that the pressor foot bar should be held firmly and
securely in its position during the operation of the machine, should yield only in
a vertical direction, and should not twist or turn in its bearings, and in putting on
different attachments it is also desirable to have said bar vertically adjustable.
These objects are attained and at the same time a uniform and easily regulated
vertical spring pressure on said bar is secured by the following construction and
arrangement. The said foot bar R has secured to it by n set scrow ? the
bracket P composed of a ring or collar encircling the bar and made deep enough
to give a long surface bearing on such bar when drawn up against it by the action
of the screw p and also provided with a projection or arın the upper surfaco of
which is grooved to receive the free end of the presser bar spring p¹. The free
end of such spring fits closely in this groove and as its other end is attached to
the arm of the machine so that it cannot move laterally and as the spring is mado
to yield only in a vertical direction the bar is thus held firmly against turning or
twisting while it can be readily adjusted vertically by loosening the set screw ?
sliding the bar up or down through the ring and resetting the screw. The amount
of vertical spring pressure on said bar is regulated by the thumb screw p²,
tapped into the arm of the machine and pressing on said spring between the point
where it is secured to the arm and the point where it rests on anid bracket P.
This bracket P is also formed and arranged so as to be acted on by the cam lever
commonly used as a lifter.
What is claimed as the Invention is:―
First. A frame for supporting and carrying the feed wheel of a sewing machine
provided with a lug through which it is attached to said machine beneath the bed
plate by means of a hinge pivot and also provided with a set screw passing through
the outer end of said lug and adapted to raise or lower said frame and support it
in the required operative position by pressing against the bed of such machine at a
point outside said hinge pivot.
Second. In combination with the said frame provided with said lug, hinge
pivot and set screws, the feed wheel or ring O with mechanism for driving it
substantially as described.
Third In combination with the said frame provided with said lug hinge pivot
and set screw, and with said feed wheel and mechanism for driving it, the
mechanism for adjusting and controlling the extent of the feeding movement of
said wheel substantially as described.
Fourth. The mechanism herein before described for giving to the shuttle
oscillating shaft the required movement through an arc in excess of a half circle ;
to wit, a rock shaft, adapted to receive a given motion from a crank on the main
driving shaft by a connection pivoted to one of its arms, and provided with
another arm longer than the distance between the centres of said shaft and of a
parallel oscillating shaft, a link having one end pivoted to said arm and the
other pivoted to the end of a crank on the said parallel oscillating shaft, said

page_text: crank being shorter than said last named arın, and the said oscillating shaft, all
connected and arranged substantially as described.
Fifth. A shuttle race for an oscillating shuttle provided with an elastic side or
flange substantially as described.
Sixth. A sewing machine shuttle constructed in two portions hinged together
one of said portions having a clasp spring rigidly attached to it at a point opposite
the hinge the free end of which spring is adapted to bear on and press against a
projection of the other portion at a point beyond said hinge thereby holding the
two portions together with an elastic pressure substantially as described.
Seventh. The combination with a sewing machine shuttle constructed of two 1
portions hinged together and having a clasp spring to hold the two portions closed
together with an elastic pressure and nip the thread between them of a lighter
spring which tends to press the two parts asunder and so diminish the pressure of
the two parts of the shuttle upon the thread substantially as described
Eighth. The combination with a sewing machine shuttle constructed in two 1
portions hinged together and held closed by a clasp spring, of a spring blade,
carried on the inner face of one portion and caused to bear upon the thread and
press it against the inner face of the other portion for the purpose of putting the
requisite tension upon the thread substantially as described.
Ninth. The combination with a sowing machine shuttle constructed in two 2
portions hinged together and held closed by a clasp spring of a light spring X³,
carried by the clasp spring and made to bear lightly against one side of the bobbin
to keep it from shaking about and rattling substantially as described.
Tenth. The adjustable slack thread controller hérein before described consisting
substantially of the receptacle, coil spring, moveable collar and set screw all 2
combined and arranged substantially as and for the purposes set forth.
Eleventh. The adjustable presser-bar bracket P attached to said presser bar
and adapted to receive the spring and be acted upon by the lifter for the purposo
of-raising such bar..
-
In witness whereof I the said Sydney Pitt have hereunto set my hand
and seal this fourteenth day of October in the year of our Lord One
thousand eight hundred and eighty two.
AVDVOY
חרדלר
1