IMPROVEMENTS IN SEWING MACHINES
Year: 1876

page_text: LETTERS PATENT to Francis Perks, of Wolverhampton, in the County of
Stafford, Ironfounder, for the Invention of "IMPROVEMENTS IN SEWING
MACHINES." A communication from abroad by Joseph Butcher, of the City,
County, and State of New York, in the United States of America, Japanner.
PROVISIONAL SPECIFICATION left by the said Francis Perks at the Office
of the Commissioners of Patents on the 6th September 1876.
FRANCIS PERKS, of Wolverhampton, in the County of Stafford, Ironfounder,
"IMPROVEMENTS IN SEWING MACHINES"
This Invention relates to that class of sewing machinos which are provided with
a reciprocating shuttle, and make a lock stitch. It consists essentially in the con-
struction of parts whereby two complete stitch movements of the needle, shuttle,
and feed mechanism are produced by one rotation of the driving cam wheel, thus
completing two stitches at the said revolution, although but two movements are
contemplated, that number being thought best, two or more movements may be
produced without essentially varying the construction of the cam wheel
The Invention also consists in the peculiar consti uction and anangement of the
feed mechanism; the novel construction of the shuttle carier and take-up; the
novel construction of the cloth plate and bed, and various combinations which will
be more fully described hereafter.
I construct the base with an overhanging arm secured thereto, or forming a part
of the same. This supports the operative mechanism, and may be cast hollow in
the usual manner. I employ a combined driving cam, belt wheel and fly wheel,
which constitute the only rotating part of the machine. This cam is mounted upon
the cast arm by means of a bolt stud or screw on which it revolves as an axis; in
the face of the cam a groove is cut to impart motion to the needle-arm; this arm is
pivoted and bears on its rear end a convex faced friction roller which engages the
cam groove in the can; the groove in the cum receives a driving belt of the usual
kind; in the present construction the groove in the cam is essentially dual, that is,
the sweep has an exact counterpart, each serving to produce an up-and-down motion
of the needle bar which is linked to the front end of the needle arm, and plays in
vertical guides in the head of the fixed arm.
Price Gd1

page_text: Those portions of the cam groove connecting the sweeps are concentric with the
axis and produce no motion in the needle arın, but permit it to remain at rest while
the shuttle passes through the loop of the upper thread. By this arrangement it
will be seen that two stitches are made at each revolution of the cam wheel, but to
produce this result it is necessary in my construction that the shuttle shall be double
nosed, and the feed make also two movements at one revolution of the cam wheel;
this construction I will now describe -To the cam wheel is attached by means
of a screw or wrist, a connecting bar or rod which takes hold of a vibrating arm or
crank rigidly affixed to an oscillating shaft having bearings in the base.
Every revolution of the cam wheel produces one complete oscillation or vibratory
movement of the shaft, to the front end of which are secured the arm bearing the
shuttle carrier and the various cams for operating the feed bar; thus each revolution
of the cam wheel communicates a reciprocatory vibration to the shuttle in the
carrier, once forward and once back, making a stitch each way, the feed bar has
four motions, up, forward, down, and back, the front end of the bar bears a serrated
head, as usual, and the rear end has a bearing in a cavity in the casting, where it
is acted upon by the stitch regulator which is controlled by a thumbscrew; in the
under side of the feed bar head is a socket that receives the upper extremity of an
upright vibrating lifter which is slotted at the lower end, the slot engaging a pin or
screw in the casting; the lower end of this lifter rests on a lifting cam pivoted to
another cam affixed rigidly to the extremity of the shaft, this latter cam gives the
forward motion to the feed bar through the medium of a bell crank and link which
connects the upper arm of the bell crank and the feed bar; a simple spiral spring
attached to the feed bar and to the base and arranged at a suitable angle seives to
draw the feed bai down and back, behind the lifting can is a tappet cam mounted
loosely on the shaft and provided with shoulders to catch under the wings of the
lifting cam, and tappets or arms to catch against bevilled faces or shoulders on the
casting.
The operation of the feed mechanism is as follows, as the shaft oscillates in one
direction, one end of the lifting cam now resting on the shoulder of the tappet cam
passes under the end of the lifter and lifts the head of the feed bar; at this instant
one branch of the cam passes under the arm of the bell crank and drives the feed
bar forward just before the bar reaches the end of its stroke, one arm or tappet of
the tappet cam engages the fixed shoulder on the casting and the cam is detained
while the lifter cami is carried on until the end of the same drops off the shoulder,
thus permitting the spring to draw down the feed out of contact with the goods;
the return oscillation of the shaft now begins, and produces precisely the same series
of motions in the feed as above described, the opposite sides of the cams being pro-
vided with like arms, shoulders and surfaces.
The shuttle carrier is mounted igidly on the extremity of the vibrating arm and
consists of a bed to which is hinged a cover habitually thrown into an upright
position by means of a spring, one shoulder of the cover is squared, and a spring
catch pivoted and habitually thrown forward by some form of spring is arranged to
catch beneath the squared shoulder of the cover and hold the said cover when
pressed down over the shuttle; when the shuttle is in place and the cover is pressed
down to keep it there, the catch is maintained in its position beneath the squared
shoulder of the cover, and the latter cannot fly up until the catch is pressed back,
when the cover is pressed down the catch slips into its place of itself and no further
manipulation is necessary; by this simple device, I supply a means of readily
removing and replacing the shuttle, and provent the possibility of its flying out
when the machine is in operation.
To get at the shuttle and other mechanism beneath the cloth plate it has been
customary to provide a sliding plate in the same, or to make the entire plate
removable, or both.
In my improved machine the cloth plate is divided centrally into two parts, the
one part being fixed to the immovable base, and the other part fixed to a movable
part of the base hinged to the latter and arranged to be thrown open so as to give

page_text: access to the interior, when closed it may be secured by a spring catch or some
equivalent device; the central part of the cloth plate is perforated for the reception
of the feed.
The needle bar is provided with a shoulder or projection which engages as the
said bar noves up an arm of a bell crank pivoted to the face plate and resting in a
cavity behind the same; this crank is provided with a spring, and its pivot is carried
through the said face plate, and provided with a take-up wire the toothed extremity
of which is perforated to receive the upper thread, and arranged to operate in con-
nection with the staple; this forms a simple and efficient take-up mechanism which
is not liable to wear or become easily deranged; the upper thread passes from the
spool through the upper tension, thence through an eye and an aporture in the
upper extremity of the needle bar to the take-up, and thence to the needle as usual.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Francis Perks in the Great Seal Patent Office on the 6th March
1877
FRANCIS PERKS, of Wolverhampton, in the County of Stafford, Manufacturer,
"IMPROVEMENTS IN SEWING MACHINES " A communication from abroad by Joseph
Butcher, of the City, County, and State of New York, in the United States of
America.
This Invention relates to that class of sewing machines which are provided
with a reciprocating shuttle and make a lock stitch. It consists essentially in
the construction of parts whereby two complete stitch movements of the needle,
shuttle, and feed mechanism are produced by one rotation of the driving cam wheel,
thus completing two stitches at the said revolution, although but two movements*
are contemplated, that number being thought best; two or more movements may be
produced without essentially varying the construction of the cam wheel.
'
The Invention also consists in the peculiar construction and arrangement of the
feed mechanism, the novel construction of the shuttle carrier and take-up, the novel
construction of the cloth plate and bed, and various combinations which will be inore
fully described hereafter.
In the Drawings Figure 1 is a longitudinal vertical mid-section of my machine.
Figure 2 is a transverse section of the same taken in the plane of the line x, x, in
Figure 1.
Figure 3 is a plan illustrating the improved cloth plate and bed.
Figure 4 is a detached elevation of the driving cam wheel.
Figure 5 is an enlarged view shewing the take up.
Figures 6 and 7 are respectively a plan and sido elevation of the shuttle carrier
detached and enlarged.
Figure 8 is a detached front view showing the feed cams and shuttle carrier.
Let (A) represent the base and (B) an overhanging arm secured thereto or form-
ing a part of the same. This supports the operative mechanisın and may be cast
hollow in the usual manner (C) is a combined driving-cam belt-wheel, and fly
wheel, which constitutes the only rotating part of the machine.
This cam is
mounted upon the cast arm (B) by means of a bolt, stud, or screw (a) on which it
revolves as an axis.
In the face of the cam a groove is cut to impart motion to the needle arm (D).
This arm is pivoted at (c) and bears on its rear end a convex faced friction roller (d)
which engages the cam groove in the cam (c) as shewn. At (b) is shewn a groove
in the cam to receive a driving belt of the usual kind. In the present construction
the groove in the cam is essentially dual, that is, the sweep or part (c) is an exact
counterpart of (c¹), each serving to produce an up-and-down motion of the needle

page_text: bar (E) which is linked to the front end of the needlo arm and plays in vertical
guides in the head of the fixed arm (B).
Those portions of the cam groove connecting the sweeps (e, e¹), are concentric with
the axis (a) and produce no motion in the needle arm, but permit it to remain at
rest while the shuttlo (g) passes through the loop of the upper thread. By this
arrangement it will be seen that two stitches are made at each revolution of the cam
wheel (c) but to produce this result it is necessary in the construction that the
shuttle shall be double nosed and the feed make also two movements at one
revolution of the cam wheel (c); this construction I will now describe:-To the
cam wheel c is attached by means of a screw or wrist (h) a connecting bar or
rod (F) which takes hold of a vibrating arm or crank (G) rigidly affixed to an
oscillating shaft (H) having bearings in the base (A) as shewn.
Thus
Every revolution of the cam wheel produces one complete oscillation or vibratory
movement of the shaft (H), to the front end of which are secured the arm (i) bearing
the shuttle carrier (5) and the various cams for operating the feed bar (K)
each revolution of the cam wheel communicates a reciprocatory vibration to the
shuttle in the carrier, once forward and once back, making a stitch each way. The
feed bar has four motions, up, forward, down, and back; the front end of the bar
bears a serrated head as usual, and the rear end has a bearing in a cavity in the casting
at (1) where it is acted upon by the stitch regulator (m) which is controlled by a
thumbscrew (n). In the under side of the feed bar head is a socket that receives the
upper extremity of an upright vibrating lifter (o) which is slotted at the lower end,
the slot engaging a pin or screw in the casting The lower end of this lifter rests on
a lifting cam (p) pivoted to another cam (r) affixed rigidly to the extremity of the
shaft (H). This latter cam gives the forward motion to the feed bar through the
medium of a bell crank (8) and link (t) which connects the upper arm of the bell
crank with the feed bar. as shown A simple spiral spring (u) attached to the
feed bar and to the base (A) and arranged at a suitable angle, serves to diaw
the feed bar down and back. Behind the lifting cam (2) is a tappet cam (1)
mounted loosely on on the shaft (H) and provided with shoulders to catch under
the wings of the lifting cam and tappets or arms to catch against bevilled faces or
shoulders (u, v), on the casting.
The operation of the feed mechanism is as follows:-As the shaft H oscillates in
one direction one end of the cam (7) now resting on the shoulder of the cam (9) passes
under the end of the lifter (o) and lifts the head of the feed bar (K) At this instant
one branch of the cam (7) passes under the arm of the bell crank (s) and drives the
feed bar forward Just before the bar reaches the end of its stroke one arm or tappet
of the cam (9) engages the fixed shoulder (v) on the casting and the cam is detained
while the lifter cam (p) is carried on until the end of the same drops off the shoulder,
thus permitting the spring to draw down the feed out of contact with the goods.
The return oscillation of the shaft (H) now begins, and produces precisely the same
series of motions in the feed as above described, the opposite sides of the cams being
provided with the like arms, shoulders, and surfaces as shewn,
The shuttle carrier (1) (shown in detail in Figures 6, 7, and 8) is mounted rigidly
on the extremity of the vibrating arm (i), and consists of a bed (g¹) to which is
hinged a cover (¹) habitually thrown into an upright position by means of a
spring (), as shown. One shoulder of the cover is squared at (¹) and a spring
catch (¹) pivoted at (7) and habitually thrown forward by some form of spring is
arranged to catch beneath the squared shoulder (¹) of the cover, and hold the said
cover when pressed down over the shuttle. When the shuttle is in place and the
cover is pressed down to keep it there the catch is maintained in its position
beneath the squared shoulder of the cover, and the latter cannot fly up until the
catch is pressed back. When the cover is pressed down the catch slips into its place
of itself and no further manipulation is necessary, by this simple device I supply a
means of readily removing and replacing the shuttle, and prevent the possibility of
its flying out when the machine is in operation
To get at the shuttle and other mechanism beneath the cloth plate it has been

page_text: customary to provide a sliding plate in the same, or to make the entire plato
removable, or both
In my improved machine, with reference particularly to Figure 3, (I, I¹) is the
cloth plate divided centrally into two parts, the part I being fixed to the immovable
base (A) and the part (I¹) fixed to a movable part (A¹) of the base hinged to the
latter at (w), and arranged to be thrown open, as in the Figure, so as to give access
to the interior. When closed it may be secured by a spring catch (3) or some
equivalent device. The central part of the cloth plate is perforated for the reception
of the feed, and this portion of the plate may form part of the section (I) as shown.
In Figures 2 and 5 is shewn my improved take-up. The needle bar (E) is
provided with a shoulder or projection (a¹) which engages as the said bar moves up
an arm of a bell crank (6¹) pivoted to the face plate (J) and resting in a cavity
behind the same. This crank is provided with a spring (c¹), as shown, and its pivot
is carried through the said face plate and provided with a take-up wire (), the
hooked extremity of which is perforated to receive the upper thread and arranged
to operate in connection with the staple (f), as shown in Figure 5; this forms a
simple and efficient take-up mechanism which is not liable to wear or become easily
deranged (B¹) is the spool wire; (C) the upper tension; (D¹) the cloth presser;
and (E), the needle, none of which possess special novelty. The upper thread
passes from the spool through the upper tension, thence through an eye and an
aperture in the upper extremity of the needle bar to the take-up, and thence to the
needle, as usual.
Having thus described the said Invention, and the manner in which the same is
to be performed, I claim,―
(First). In a sewing machine having but one rotary element a single wheel (c)
constructed so us to combine the functions of a belt wheel, a fly wheel, and a driving
cam, for all of the mechanism substantially as set forth.
(Second). In a sewing machine, a driving cam wheel having a groove arranged to
act upon the end of the needle arm, and give the latter two or more complete
reciprocating or stitch motions to one revolution of the said cam, in connection with
a feed mechanism making a like number of motions, so that two or more complete
stitches may be made at each revolution of the said driving cam, substantially as
set forth.
-
(Thud). The cam wheel (c) having a cam groove constructed as described in
combination with the needle arm (D), oscillating shaft (H), and link or rod (F), all
arranged to operate substantially as set forth.
(Fourth). The combination of the cam wheel (c) grooved as described, the needle
arın (D), oscillating shaft (H), and the feeding mechanism, constructed as herein set
forth.
(Fifth) The shuttle carrier (5), consisting of the spring cover (¹) and spring
catch (K¹) mounted upon a suitable bed (¹), and all arranged to operate substantially
as shewn and for the purposes set forth.
(Sixth) In a feed mechanism for sewing machines the combination of the lifting
cam (p) and tappet cam (9) with suitable stops (v, v,) when arranged to operate in
the manner substantially as set forth
(Seventh). In a feed mechanism for sewing machines the combination of the
cam (1) having two branches or arms, as shewn, with the oscillating shaft (H) and
the bell crank (8) when arranged to operate substantially as set forth
(Eighth). The combination of the lifting cam (p), loose tappet cam (q), cam (r),
oscillating shaft (H), and feed bar (K), when arranged to operate substantially as
set forth.
(Ninth). The combination of the feed bar (K), cams (p), (q), and (r), lifter (0),
bell crank (8) or its equivalent, and spring (u), to form a feeding device for a sewing
machine when constructed and arranged to operate substantially as herein shewn
and specified.
(Tenth). In a sewing machine the part (A¹) of the base bearing the part (T¹) of

page_text: the cloth plate hinged to the fixed base, substantially as represented, and arianged
to be swung open, as shewn with reference to Figure 3.
(Eleventh). In a sewing machine the improved take-up, consisting of the pro-
jection (a) on the needle bar, the bell crank (¹), the spring (c¹), and hooked
perforated wire (d') when combined and arranged to operate substantially as herein
set forth.
In witness whereof, I, the said Francis Perks, have hereunto set my hand
and seal, this Fifth day of March, in the year of our Lord One thousand
eight hundred and seventy-seven.