Improvements in Sewing Machines.
Year: 1895

page_text: Date of Application, Eth Oct., 1895-Accepted, 5th Sept., 1896
[Communicated from abroad by THE AMERICAN SPECIAL MACHINE COMPANY,
LIMITED, Manufacturers, of 47 Leonard Street, New York, U.S.A.]
Improvements in Sewing Machines.
I JOHN WILLIAM MACKENZIE of the Firm of Wheatley and Mackenzie
Engineers and Patent Agents of 40 Chancery Lane London 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 improvements in sewing machines and feeding mechanism
therefor, and has for its principal object to provide a machine having a cylindrical
bed plate containing certain of the operating parts, upon which bed plate hollow
articles may be placed and sewed with far greater facility than on an ordinary flat
bed machine. The invention is designed for use especially in the sewing of shoes
for placing rows of stitches on the vamps thereof, but it is also adapted for use
in sewing other tubular articles such as knit goods, hosiery, and other fabrics, both
knitted and otherwise.
In the accompanying drawings which illustrate the invention,
Figure 1 is a perspective view of a sewing machine constructed according to the
present invention;
Figure 2 is a side elevation, the cylindrical casing being broken away on one
side; and
Figure 3 is a sectional plan view of the cylindrical casing showing the operating
parts secured therein.
Figures 4 and 5 represent in plan and vertical section respectively, details of the
connection between the main shaft and feed rocking frame.
Figure 6 is a front view of the machine, the end of the cylinder being
removed.
Figure 7 is a view looking from the rear end of the cylindrical bed plate
showing the rotary take-up mechanism; and
Figures 8 and 9 are sections on lines 8-8 and 9-9 respectively of Figure 3.
Figure 10 is a perspective view of a portion of the casing with the various parts
shown in an enlarged form.
Figures 11 and 12 are detail views respectively in side elevation and plan of the
outer end of the looper shaft showing a conical head to which the looper rocker is
attached.
Figure 13 is a side elevation of the front end of the feed shaft carrying the feed
dog supporting frame.
Figure 14 is a detail view.
Figure 15 shows the looper in position for the loops of upper thread to descend
through the loop of under thread at the rear side of the looper.
Figure 16 shows the needles and loops of upper thread entering the loop of
under or looper thread.
Figure 17 shows the looper retracted from the loops of upper thread preparatory
to moving the looper laterally in the direction of the feed.
Figure 18 shows the needles and loops of thread thrown out from the eyes of
the needle by a full descent and partial rise of the needles.

page_text: Figure 19 shows the looper and the loop of its thread as passed through the two
loops of thread carried by the two needles, the looper passing close to the rear
sides of the two needles or the farthest sides of the two needles in the direction of
the feed.
Figure 20 represents the two needles raised, it being understood that the feed
is taking place, the loops of needle or upper thread being held closely by the
looper.
Figure 21 is a perspective view of the stitch formed on this machine, with the
under side up.
Figure 22 is a perspective view with the right side up.
Figure 23 is a bottom plan view of the same stitch, it being understood in
Figs. 15-23 that the needles are shown somewhat farther apart than they
actually are in the machine in order that the formation of the stitch may be better
illustrated.
I will first describe the machine as a whole and afterwards take up the feeding
mechanism. A is the standard or base plate secured to a supporting bench or table
in any desirable manner, and B is the overhanging arm or goose-neck, so called.
D is the needle-arm pivoted on the goose-neck and having a downward extension a
to which the looper actuating rod is attached in the well-known manner. The
driving belt wheel is represented at c and is carried on the end of the main shaft Q,
the needle arm being rocked by a suitable eccentric d and connecting rod e.
Secured to the standard or base plate is the cylindrical casing E, the lower part of
which fits on a ledge fou the base plate and is secured thereto. This cylindrical
casing is enlarged at its rear end as shown more clearly in Figure 10 to accommodate
the parts such as the rotary take up and co-operating mechanism which extend
above the plane of the main shaft. The upper part of the casing is removable
and at its front is provided with a downwardly extending pin h which fits a slot
formed in a cut-away portion i of the casing. In front of the removable plate and
upon projecting edges of the casing is secured the throat plate H of the machine
curved to conforin to the cylindrical casing and having the necessary slots for the
passage of the needle or needles and feed dog. The end of the cylindrical casing
is closed by a conical shaped cap j hinged to the lower part of the casing. It will
thus be seen that when the upper plate or cover is in position and the cap shut,
the cylindrical casing is entirely closed and acts as a work plate for the gols to
be sewed. The cover of the cylinder at its rear end is provided with a pin k
adapted to register with a slot in the clamping piece / pivoted to the upwardly
extending enlarged part of the lower portion of the casing.
The needle arm D is provided with the ordinary thread eyelets and is attached
to the needle bar L by a link connection m.
I have herein shown the needle bar as carrying two needles set closely together
and held from lateral deflection by the guide foot a on one side and the roller
presser foot M on the other side, the guide foot being attached to the ordinary
presser foot bar N while the roller presser foot is of the usual construction
supported by the supplemental presser bar O.
The needle bar and presser bars reciprocate in guides carried by the goose-neck
of the machine and upon a post o extending vertically from the top thereof is
supported an oil cup p from which oil is fed to a piece of sponge or other absorbent
material which keeps the needle threads lubricated.
Longitudinal deflection of the needles is prevented by the needle guard secured
upon the under side of the curved throat plate and the guard finger travelling in
unison with the looper.
The operative parts of the machine for acting on the lower thread and feeding
forward the material are located within the cylindrical casing E.
Q is the main shaft of the machine upon one end of which is the belt wheel e
said main shaft passing through the upper part of the base plate of the machine
having one of its bearings therein ail at its other end having a bearing in the
standard y carried by the lower part F of the cylindrical casing.

page_text: Near the inner end of the casing upon the main shaft is located the rotary
take up R composed of cam shaped disks made in one piece with a collar secured
to said shaft, and stationary throw off S, the thread being compelled to ride over
the edges of the disks by the guides rr the guides and stationary throw off being
secured within the enlarged part of the cylindrical casing.
In the rotation of the disks the straight edges thereof catch the portion of thread
between the guides and carry it up with them (thereby taking up the slack from
the loops) until the throw off replaces it, at which time the looper is ready for
another forward impulse and not only draws the slack, thus temporarily taken care
of by the take up but a stitch length in addition.
Actuated from the main shaft by an eccentric thereon working in a fork s is a
shaft T to which the fork is secured, said shaft having a bearing in the lower part
of the standard g and in a second lug or standard g near the front of the cylinder.
This shaft is formed with an extension T' to which the crank which carries
the looper u is pivoted, this crank being connected by a ball joint with the end of
the looper rod u connected with the needle arm extension. The pivotal connection
of the crank t with the shaft T is made by providing the extension or head T¹ with
a conical or ball projection over which the socket in the looper crank t fits.
It will thus be seen that in the movement of the main shaft the looper rod will be
reciprocated back and forth thus reciprocating the crank to which the looper
is attached backward and at the same time the shaft T will be rocked thus giving
the said crank a side-wise movement and owing to the ball joint connection between
the crank and the end of the looper rod both movements are allowed to take place.
To a lug or standard on the inner ends of the looper rocker shaft T are attached
two springs vv extending vertically which are brought together to clasp the thread
between them at the proper intervals by contact of the spring v' with the upwardly
projecting arm U secured to the casing.
When the looper begins its forward movement and the springs rock away from
the arm U they automatically open, and free the thread which can then be drawn
by the looper without resistance.
In the backward movement of the looper however, the springs rock toward the
projecting arm U and are closed, thereby gripping the thread and holding it tight
during the said backward movement of the looper.
Connected to the looper crank and moving in unison with the looper rocker
is the guard finger w of ordinary construction between which and the looper,
the needles pass in the forward movement of the looper, thus preventing deflection
of the needles in that direction, while the guard in the throat plate guides the
Deedles on the side on which it is located.
I will now proceed to describe the feeding mechanism used on my machine.
(!) represents a shaft running nearly the whole length of the cylinder and
having bearings in the standards qq' on the inside of said cylinder.
This shaft has fixed to it two arms (2) forming a fork between the prongs
of which fork a can. (3) on the main shaft revolves thereby oscillating said
shaft (1).
At its outer end the shaft 1 is provided with a curved arm 4 fixed to it, and
forming an extension thereof beyond the cylinder proper. At its outer end this
curved arm is provided with an opening within which is placed a stud shaft or pin 5
to which said curved arm is rigidly attached.
At a point nearer the center of the cylinder the shaft 1 is provided with a
laterally extending lug or standard 6 rigidly attached to it, so that it together with
the curved arm 4 rocks with the shaft 1.
This lug 6 is provided also with a stud, shaft or pin 7, so arranged to be
approximately in its line with the stud or pin 5.
Loosely mounted on the studs or pins 5 and 7 is the rocking crank frame.
This consists of three parts, the forward longitudinal arm 9, to which is removably
12 curved to
secured in the dovetailed groove 10, the shank 11, of the feed
conform to the shape of the cylinder, and extending up through an opening in the

page_text: arm 15.
curoat plate; the short connecting part 14 and the rearwardly extending longitu linal
This crank frame is preferably made all in one piece.
While I have shown the part 9 of the crank frame as provided with lugs 16, 16
having openings fitting over the studs or pins 5, 7 it will be understood that the
studs or pins may be secured to the arm 9 and pass loosely through the openings on
the lug 6 and curved arm 4. The outwardly extending part 15 of the frame
is provided with an opening in which is secured the stud or shaft 17. Upon one
end of this shaft is mounted so as to swing thereon one end of the crauk 18, which
has a split bearing at its opposite end encircles a sleeve 19 surrounding the axial
stud pin or shaft 20, such sleeve being held from longitudinal displacement by the
nut 21 on the threaded end of the shaft or pin 20.
This shaft or pin 20 is herein shown as provided at its inner end with a circular
enlargement or head which is fitted in a slot 22 formed in a crank disk 23 attached
to the end of the main shaft. This slot is formed with a contracted front opening
so that the head of the head of the stud 20 is prevented from longitudinal displace-
ment. To permit of adjustment of the stud 20 in the slot and thereby vary
the throw of the crank 18 I have provided a screw 24 which passes through the
head of the stud 20.
The screw is secured to the crank disc by means of the clamping plate 25 having
a slot which fits the screw beneath the head thereof, said clamping plate being
secured to the periphery of the crank disc by screws 26 as shown.
To accomplish the adjustment of the stud 20 without changing the position of
the screw 24 with respect to the crank disc, I have provided said screw with a
collar 27 just below the clamping plate 25 so that longitudinal movement of the
screw 24 is prevented by the head and collar respectively, so that in the turning of
the screw the head on the stud 20 will be moved up or down thus changing the
point of connection of the crank disc in the main shaft, with the crank 18, thereby
altering the throw of said crank and varying the amount of forward and backward
movement of the rocking frame and feed dog.
It will be readily understood therefore, that by reason of the rocking connection
of the feed or carrying frame with the shaft 1 and the crank connection of said
frame with the main shaft that the vertical and forward and backward movements
of the feed dog are effected and also that by the adjustment of the head of the stud
or bolt 20 in the slot of the crank disc the amount of tnrow of the rocking frame is
varied and thereby the length of stitch regulated.
The formation of the stitch is shown clearly in Figures 15-23 inclusive and is
well known in the art as the three thread chain stitch, in which the loops of two
needle threads are interlaced with a single under thread carried back and forth by
a looper. Referring now to said figures, supposing the two needles and the looper
to be threaded each with its own thread and a stitch to have been made in the
naterial lying on the usual bed plate and supposing the two needles to be
descending toward the material and the feed to have taken place, with the parts
referred to in the positions stated the looper will occupy the position Figure 15
with relation to the needles, and to make the next stitch the needles will descend
at the rear side of the looper u and pass into the loop of looper thread, each needle
entering the said loop at the farther side of the loop of its own thread not held on
the looper shank as shown in Fig. 16. In this condition the needles will continue
to descend as shown in Figure 17 and the looper will be drawn backward to the
left, past the left-hand needle and will then be moved somewhat laterally in the
direction of the feed of the material and the needle bar commencing to rise,
the needles will throw out their loops of needle thread as in Figure 18 in the usual
manner and the looper u coming forward as the needles rise will enter both loops
of upper or needle thread at the rear sides of the needles in the direction of the
feed of the material as in Figure 19 and the looper having engaged the loops of
needle thread the necules will be fully lifted, drawing their loops closely about the
looper and the feed will then take place, and as the feed takes place the looper will

page_text: be moved slightly in the direction opposite the direction of feed to thus enable it
to occupy a position at the front sides of the needles as the latter again descend to
form a new stitch, the said needles again entering a new loop of needle thread.
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 :-
1. A sewing machine comprising a cylindrical casing, a main shaft extending
within the same, feeding and looper shafts also arranged within the casing and
oscillated from the main shaft, one of said shafts being arranged in a plane to one
side of the main shaft but parallel therewith and the other in substantially the same
vertical plane as the main shaft, a rocking feed dog carrying frame pivote to and
entirely supported by the feed shaft and operatively connected to the main shaft,
and a looper connected to the looper shaft; substantially as described.
2. A sewing machine comprising a main shaft, a cylindrical casing into which
the main shaft extends, a feed operating shaft driven from the main shaft, a third
shaft extending lengthwise of the casing parallel with and below the main shaft
with its forward end in advance of the forward end of the main shaft with
connections between the main shaft and the third shaft for operating the latter and
a looper connected to the forward end of the third shaft and rocked thereby ;
substantially as described.
3. A sewing machine comprising a main shaft, a cylindrical casing into which
the main shaft extends a second shaft extending lengthwise of the casing and
parallel with the main shaft but the forward end in advance of the forward end of
the main shaft, connections between the main shaft and the second shaft for
operating the latter, a rocking feed dog frame pivotally connected to and entirely
supported by the second shaft, a third shaft extending length-wise of the casing
and parallel with and below the main shaft with its forward end in advance of the
forward end of the main shaft with connections between the main shaft and the
third shaft for operating the latter and a looper connected to the forward end of
the third shaft and rocked thereby; substantially as described.
4. In a sewing machine suitable stitch forming mechanism, a cylindrical casing
enlarged at one end, feeding and looper mechanisms contained within said casings
and a rotary take-up mechanism supported in the enlarged portion; substantially
as described.
5. A sewing machine comprising a cylindrical casing entirely closed on its under
side, and having a plurality of standards therein, a removable top plate curved to
conform to the shape of the cylinder extending throughout the length thereof, a
hinged cap for said cylinder, a main shaft, looper rocker shaft and feed shaft
journalled in the respective standards and extending length-wise of and within the
casing whereby the parts are compactly arranged and easy of access but only from
the top or end; substantially as described.
6. A sewing machine comprising a cylindrical casing, a main shaft, arranged
lengthwise thereof and extending within the same, a rock shaft entirely within
the casing, a looper rocker connected to said shaft and extending at right angles
thereto with means for reciprocating said looper, a second rock shaft independent
of the first with connections between it and the main shaft, a feed dog carrying
trame pivotally connected to the second rock shaft and oscillated thereby with
independent connections between said frame and the main shaft, said main looper
and feed shatts being arranged so that the main shaft and the pivot points of the
feed dog carrying frame and looper rocker will be in substantially the same
vertical plane which passes through the longitudinal axis of the main shaft
whereby the parts may be compactly arranged within a minimum space; substan-
tially as described.
7. A sewing machine comprising a cylindrical casing, a main shaft extending
lengthwise of and within said casing, a looper mechanism also within the same,
a removable top plate for said casing, a tapering, hinged end cap, a feed shaft

page_text: curved at its outer ends to conform to the shape of the hinged end cap, a rocking
feed dog carrying frame pivoted at one end on the curved portion of the feed
shaft and complemental stitch forming mechanism; substantially as described.
8. In a sewing machine a suitable standard and a cylindrical casing forming
the bed plate of the sewing machine resting at its inner end upon and secured to said
standard and extending laterally therefrom, said cylindrical casing being provided
with a removable top plate curved to conform to the periphery of the cylindrical
casing and having a conical hinged end cap whereby the working parts within the
bed plate are easy of access and tubular articles may be readily placed over the
bed plate of the machine; substantially as described.
9. A sewing machine comprising a cylindrical casing, a main shaft extending
lengthwise of said easing and within the same, an under thread carrying looper
provided with a guard finger, a feeding mechanism all of said parts being contained
within the casing, a throat plate curved to conform to the shape of the casing
provided with a needle guard, complemental stitch forming mechanism and means
for reciprocating the looper and its guard finger lengthwise of the casing;
substantially as described.
10. In a sewing machine the combination with the main shaft, feed shaft, looper
shaft and means for operating the same, the feed and looper shafts extending
parallel with and in advance of the forward end of the main shaft, and the looper
shaft carrying a conical projection at a right angle thereto, of the feed dog
carrying frame supported by the feed shaft and operatively connected to the main
shaft, a looper and looper carrier supported by said conical projection and means
for oscillating the looper carrier in the direction of the length of the looper;
substantially as described.
11. A sewing machine comprising a cylindrical casing having an enlarged rear
portion, a stationary abutment within said enlarged portion, a looper rock shaft
extending lengthwise of and within said casing, a pair of vertical nipper springs
carried by the rear end of said shaft and within said enlarged portion and
operating against said abutment; substantially as described.
12. In a sewing machine a cylindrical casing forming a bed plate, a comple-
mental stitch forming mechanism, said bed plate comprising the lower part
within which the feeding and looper mechanisms and a portion of the main shaft are
supported, an upper removable plate having an upward extension at its rear end
and the rotary take-up mechanism operating therein, a curved throat plate secured
to the forward part of the casing and provided with openings for the passage of
the needles and feed dog; substantially as described.
13. In a sewing machine a cylindrical casing forming the bed plate of the
machine, suitable stitch ferming mechanism, said bed plate comprising a lower part
within which certain parts of the stitch forming mechanism are supported and
open at its top a removable top plate adapted to cover said opening and a cap for
closing the end of the cylinder; substantially as described.
14. In a sewing machine the combination with the cylindrical casing, a main
shaft, extending lengthwise of the casing, a feed operating shaft arranged below
and to one side the main shaft with its forward end in advance of the forward end
of the main shaft, connections between the main shaft and the feed operating shaft
for oscillating the latter, a feed dog rocking frame pivoted to the feed shaft with
connections between said rocking frame and the main shaft, a looper rocker shaft
arranged below the plane of the main shaft with its forward end in advance
thereof, said looper rocking shaft being also below the plane of the feed operating
shaft, a looper rocker pivoted to said looper rocker shaft and extending at right
angles thereto, a looper attached to said rocker and means for oscillating the
looper substantially as described.
15. In a sewing machine and in combination the main shaft, the cylindrical
casing into which the main shaft extends, said main shaft being arranged in the
upper portion of the cylindrical casing, a feed operating shaft arranged adjacent to
the side of the casing and with its forward end in advance of the forward end of

page_text: the main shaft, a rocking frame pivotally connected to the second shaft whereby
in the movement of the second shaft the frame is rocked up and down, a feed dog
carried by the rocking frame and a connection between said rocking frame and the
forward end of the main shaft whereby the feed dog is given a forward and
backward movement, a third shaft arranged in the bottom part of the casing in
substantially the same vertical plane as the main shaft but with its forward end in
advance of the forward end of said main shaft, a looper arranged on the inside of
the casing opposite the feed shaft and pivoted to the said third shaft with
means for reciprocating said looper length-wise of the casing; substantially as
described
16. A sewing machine comprising a main shaft, a cylindrical casing into which
the main shaft extends, a second shaft extending lengthwise of the casing and
parallel with the main shaft but the forward end in advance of the forward
end of the main shaft, connections between the main shaft and said second shaft
for operating the latter, a rocking frame pivotally connected to the second shaft
its pivot points being in substantially the same horizontal plane therewith whereby,
in the movement of the second shaft, the frame is rocked up and down, a
transversely arranged feed dog carried by the rocking frame, said rocking frame
having a longitudinal rearwardly extending part in close proximity with the
forward end of the main shaft and a direct crank connection between the
forward end of the main shaft and said rearwardly extending part of the rocking
frame for giving the forward and backward movements to the feed; substantially
as described.
17. The combination with the main shaft of a rock shaft with connections
between the same for operating the latter, a laterally extending crank secured to
the rock shaft and provided with a stud, a second laterally extending crank on the
end of the second shaft and having also a stud in line with the stud on the first
crank, a crank frame pivotally supported on said stud in substantially the same
horizontal plane as the rock shaft whereby, in the movement of the rock shaft, the
crank frame is raised and lowered, a feed dog carried by one arm of said
crank frame, the other arm having an adjustable eccentric connection with the
main shaft and independent of the rock shaft ; substantially as described.
18. A sewing machine comprising a cylindrical casing, a main shaft extending
lengthwise of and within the same, a rock shaft parallel with the main shaft with
connections between the same for operating said rock shaft, a crank secured to the
rock shaft and provided with a stud, a second crank on the end of the rock shaft
and having also a stud said crank being curved to conform to the shape of the
casing to bring its stud in line with the stud on the first crank, said studs being in
substantially the same horizontal plane as the rock shaft, a crank frame pivotally
supported on said studs one arm of which is arranged longitudinally and carries
the feed dog the other arm having an adjustable eccentric connection with the main
shaft, said parts being all located within the casing; substantially as described.
19. The combination with the main shaft, of a rock shaft with connections
between the two for rocking the latter, a lateral extension fixed on said rock shaft,
a second curved extension secured thereon, a rocking crank frame pivotally
connected to said extensions, and having a longitudinal bar carrying the feed dog,
a stud fixed to the crank frame, a crank sleeved on said stud, and an adjustable
eccentric connection between said crank and the main shaft; substantially as
described.
20. A sewing machine comprising a cylindrical casing, a main shaft extending
lengthwise of and within the same and provided on its inner end with a slotted
disc, a rock shaft parallel with the main shaft and carrying two crauks, a rocking
frame carrying a feed deg connected with said cranks, a stud secured to one arm
of said rocking frame, a crank sleeved on said stud and encircling at its opposite
end a stud which is in adjustable connection with the slotted disc, all the parts
being located within said casing; substantially as described.
21. A sewing machine comprising a main shaft, a rock shaft with connections

page_text: between the two for operating the latter, a crank 6 secured to said shaft, a curved
crank 4 also attached thereto, a rocking crank frame having lugs 16, 16 adapted to
be pivoted to the cranks 4, 6, having also a longitudinal bar 9 carrying a feed dog
and having the parts 14, 15 and an adjustable eccentric connection located between
the part 15 of the crank frame and the main shaft and independent of the rock
shaft; substantially as described.
22. A sewing machine comprising a main shaft having on the inner end a slotted
disc, a rock shaft with connections between the two for operating the latter a crank 6
secured to said shaft, a curved crank 4 also attached thereto, a rocking frame
having lugs 16, 16 adapted to be pivoted to the cranks 4, 6 having also a longitudinal
feed bar carrying a feed dog and having the parts 14, 15, a stud secured within
said part 15, a crank 18 journalled at one end on the stud 17 and having at its
opposite end a split bearing, a stud 20 fitting at one end in the slot of the disc on
the main shaft and having a sleeve 19 fitting within the split bearing on the end of
the crank substantially as described.
23. The combination with the main shaft having on one end a slotted disc, a stud
fitting at one end in said slot, a screw passing through said stud in the slot and
provided with a collar and the clamping plate embracing the screw between the
collar and the head thereof, whereby longitudinal displacement of the screw is
prevented, a crank encircling the stud and secured at its opposite end to a rocking
frame carrying a feed dog, and means for rocking the frame and giving it vertical
movement; substantially as described.
24. A sewing machine comprising a cylindrical casing, a main shaft extending
lengthwise of and lying within the same, a rock shaft extending parallel with the
main shaft with operating connections between the two, a lateral crank secured to
the rock shaft, a second crank on the end of said shaft curved to conform to the
shape of the cylinder, a rocking crank frame pivoted to said cranks and having a
longitudinal frame, a curved feed dog secured on said arm and extending at right
angles to said arın, and a connection between the crank frame and the main shaft
for regulating the length of throw of the feed dog, all of said parts being located
within the casing, and complemental stitch forming mechanism; substantially as
described.
25. A sewing machine comprising a main shaft, a cylindrical casing, a second
shaft in operative connection with the main shaft and located within the casing, a
frame secured to and rocked by said shaft and eccentrically connected to the main
shaft, and having a longitudinally extending bar and a transversely extending
curved feed bar attached thereto; substantially as described.
26. A sewing machine comprising a main shaft, a second shaft operated thereby,
a cylindrical casing within which said shafts are supported, a rocking feed dog
operated from the rock shaft, the pivotal point thereof being in substantially the
same horizontal plane as the second shaft and approximating the longitudinal axis
of the cylinder, whereby in the oscillation of said second shaft the feed dog is raised
and lowered and swings back and forth in a plane curved to conform to the plane
of the cylinder; substantially as described.
27. In a machine having a curved bed plate, a main shaft, a rock shaft, with
means for operating the latter from the former, lugs extending laterally from said
rock shaft, a feed dog carrying frame pivoted to said lugs, the longitudinal axis of
said pivot being coincident with that of the curved bed plate, and means connecting
the main shaft with the feed dog carrying frame for giving lateral movement thereto,
whereby in the oscillation of the rock shaft the frame moves vertically on its pivot
point, the latter acting as a fulcrum on which it always swings laterally, thus
causing the feed dog to move always in a curved line; substantially as described.
Dated this 8th day of October 1895.
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.