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Патент USA US2128353

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Aug. 30, 1938.
c. w. DOWD
SEWING MACHINE FEEDING MECHANISM
Filed March 25. 1936
‘ 2,128,353
2,128,353
Eatented Aug. 30, 1938
PATENT oFncF.
UNITED STATES
SEWING
Ii'EEUlNG DIECHANISM
Charles w. Dowd, Highland Park, N. 1., Iasslgnor ,
to Willcox a Gibbs Sewing Machine Company, '
New York, N. Y., a corporation of New York
Application March‘ 25, 1938, Serial No. 70,871
‘110mm.
(Cl. 112-214)
This invention relates to sewing machine feed
ing mechanism and particularly to such a mecha
nism having a positively driven top feed roller.
The principal object of the invention is to pro
- 5 vide means to assist the feed roller , in passing
over extraordinary thicknesses of work, such as
cross seams in very heavy fabrics, which may. be
passed through the stitch-forming mechanism.
Another object is to actuate said means by
in movement of the presser-foot and particularly by
tilting movement of the foot caused by the pas
sage of the heavy thickness of work under said
foot.
.
'
The aforesaid and other objects, which will be
id 61 apparent from the detailed description and draw
ing, are realized by the present invention, the now
preferred embodiment of which is illustrated in
the accompanying drawing, wherein
Figure 1 is a perspective view of a complete ma
2'9 chine having the present invention applied there
to;
‘
Figure 2 is a front elevation of a portion of
the machine at the free end of the feed-oif-the
arm work arm and showing a very heavy thick
95 ness of work or cross-seam entering beneath the
forward end of the presser-foot and tilting the
same upward at said end;
Figure 3 is a similar view with the heavy thick-,
ness advanced to about the middle of the foot so
that the same is approximately horizontal; and
Figure 4 is a similar view with the heavy thick
ness still further advanced until it is about to
pass from beneath the rear end of the foot.
In the accompanying drawing, the invention is
35 illustrated in conjunction with a feeding mecha
nism such as set forth in Merritt Patent No.
1,837,468, dated December 22, 1931.
As shown, the machine has a framework com
prising two hollow standards “! and ii connected
4Q by a hollow bridge i2 (corresponding to parts 36,
di and 32 respectively of said patent). A hollow
work-arm extends forward from the upper end of
standard Ill in a horizontal part l3 from the out
er end of which a part I‘ depends vertically. At
its upper end the hollow standard ll curves or
bends forward to form the hollow overhanging
head portion l! of the machine frame or casing.
The standard II and its head portion i5, bridge
i2, standard ill, and parts i3, IQ of the work-arm
are all preferably integrally formed in one cast
ing. A lower horizontal work-supporting part it
of the arm extends toward the left and rearward
from the lower end of the vertically depending
part i4, terminating at its free end (which con
55 stltutes the free end 01-’ 1511? 911.14%‘? awe-arm @1391
the end oil! which the work is, fed) beneath the
overhanging head portion I! of the machine
frame and casing. Part I‘ of the work-arm is
preferably a trough-like casting and is rigidly but
detachably secured to the lower end of part I4. 5
At the free end of said part l6 there is a U-shaped
cloth-plate frame it properly positioned and re
movably secured in place. I8 is the throat plate,
or cloth plate, which is applied over the frame I‘!
and properly positioned and secured in place 10
thereon. The cloth plate l8 has needle slots (not
shown) and longitudinally extending slots l9
(Fig. l) to accommodate the rows of teeth on the
lower feed dog. 20 is a removable top cover for
the part 88 of the work-arm. Other removable 15
caps or covers are also provided to facilitate as
sembling and access to parts enclosed within the
hollow frame-work or casing, the same including
a cap it at the top of standard ii; an upright
cover 22 at the front of the head of the machine; 20
a cover 23 at the left-hand end of the machine.
24 is a folder, shown in dotted outline in Fig. 1,
and which may be of any well known suitable con
struction for interfolding edges of fabric in mak
ing felled seams and which is mounted on the 25
work-supporting part it of the work-arm. Pref
erably, for certain classes of work, the folder 24
is movably mounted .on the cover plate 20 in the
manner set forth in Lewis Patent 1,796,111, dated
March 10, 1931.
30
25 is the needle bar carrying two thread-carry
ing needles ‘2t, 21, shown in Fig. 2 with their lower
ends broken away. Other parts of the stitch
forming mechanism are not shown. 28 is a four
motion feed dog of the lower or bottom feed, hav- 35
ing rows of teeth which work upwardly through
the slots it in the cloth plate B8 in engaging and
feeding the work.
30 is the presser-foot bar vertically movable in
bearings (not shown) in the head 15 of the ma- 40
chine. M is the shank of the presser-foot having
a split hub which embraces the lower end of bar
30 and is clamped thereto by tightening screw 82.
Shank 3i extends forwardly and downwardly in
two spaced fork-like legs 83 and 34', each formed 45
at its lower end to constitute a partly cylindrical
cross-head or pivot knob 35, the cylindrical sur
faces of both knobs being on a common axis and
of the same diameter. Forward of its horizontal
pivots or pivotal axis, the presser-foot is solid and 50
includes a normally horizontal portion 38 having
therethrough elongated needle openings or, slots
31 for the needles 26, 21, respectively, and an up
wardly inclined forward end or toe portion 38.
‘Backward from its horizontal pivotal axis, the 55 .
2
3.7
2,128,358
presser-foot includes two parallel rearwardly ex
tending side bars 40 and 4|, between which the
top feed roller is positioned and works, as present
ly described. The pivot knobs 35, 35 at the lower
ends of the legs 33, 34, are engaged in their corre
sponding pivot sockets in the presser~foot by
slight relative sidewise movement. Plate 42 (Fig.
l) at its upper end embraces and is secured by a
screw 43 to leg 33 and at its lower end overlies the
end of pivot knob 35. There is a similar plate 42,
not shown, associated with leg 34, so that the two
plates thus prevent disengagement of the pivot
knobs from their sockets.
45 is a power-driven intermittently rotated top
feed wheel or roller adapted by engagement with
the upper surface of the fabric or work to inter
mittently feed or advance the same the length of
one stitch at a time, each feed movement being
timed to take place, as usual, while the needle
or needles are clear of the work. In the embodi
ment illustrated herein, the peripheral surface
of the feed roller is formed to constitute teeth
for gripping the fabric or work to be fed and
also to constitute gear teeth through which the
roller is rotated by a spiral gear 46 meshing
therewith.
41 is a top feed presser-bar of rec
tangular cross-section having vertical sliding
movement, parallel to the presser-foot bar 36, in
a suitable slideway in the head I 5 of the machine.
'» ‘At its lower end, bar 41 has a right~angle exten
sion branching into two downwardly curved
shown in Fig. 1 in contact with a part which sur_
rounds pivot stud 51. An arm 58, also prefer
ably cast integral with the tubular shaft 5|,
extends toward the front side of the machine
and carries at its outer end a block 59 adapted
to engage the underside of a stud 60 projecting
from the lower end of the feed roller bar 41. The
free end of a flat spring 66 engages and yield
ingly presses downward upon said stud 60, said
spring at its other end being pivoted on said
pivot stud 51 secured to the standard ll of the
machine. An adjusting bolt 63, engaging the top
side of the ?at spring 6|, between its pivot 51
and its engagement with stud 60, serves to in
crease or decrease the tension of the spring as
desired.
As will be readily understood downward pull
upon rod 54 by the action of a treadle or knee
actuated device (not shown) will lift the top
feed roller against the tension of spring 6|.
In addition to such means for lifting the top
feed roller from a treadle or knee-actuating de
vice, the following means are provided for hand
actuation. A bent link 64 pivoted at its lower
end to the rock arm 53 by a screw pivot 65 is
pivotally connected at its upper end to the outer
end of an arm 66 secured to the end of a shaft
61 projecting from and journalled in the wall of
the standard H of the machine frame, said shaft
carrying within said standard means (which need 30
not be herein illustrated or described) which
prevent lifting of the presser foot except when
the needles are elevated above the cloth plate.
68 is a hand lever fulcrumed to the head of the
spaced arms 48 between which the roller 45 is
journaled on a stud 49. As thus supported the
feed-roller 45 is also positioned to engage the
top surface of the fabric or work in the space be
tween the side arms 40 and 4| of the presser
foot close to the rear beveled edge of the hori
zontal solid bottom portion 36 of the presser-foot
and thus close to the point where the needles
40 penetrate the work.
.stud 10 the shank of which works in a slot in 35
The top feed roller 45 is yieldingly pressed
downward into gripping engagement with the
work by a spring 6| presently described, and may
yieldingly move up and down, not only to ac
45 commodate itself to variations of thickness of
work passing thereunder, but in response to up
stop stud 13. A spring 14 coiled about the shank
of the screw 15 screwed into the connecting bar
1|, has one end anchored in an opening in said
. and down movements of the lower feed dog 26,
thereby enabling said roller to continuously
maintain its feeding grip upon the work. The
roller 45 is power driven and intermittently ro
50 tated
to feed the work through driving connec
tions from the main shaft (not shown) of the
machine, said connections including a vertical
rotatable shaft 50, shown in dotted lines in Figs.
3 and 4, extending longitudinally within and
movable up and down with the bar 41, and the
previously mentioned spiral gear 46 which is se
cured to the lower end of said shaft.
Means for lifting the top feed roller and
presser-foot, both by hand and by foot, and for
holding them in elevated position, during intro
duction of or manipulation of, work and for other
purposes, are shown at the left-hand end of Fig.
1.
5| is a short tubular rock-shaft or sleeve ro
65 tatable on a stud 52 rigidly projecting from the
head l5 of the machine frame or casing.
A
rock-arm 53, preferably cast integral with the
said tubular shaft, extends toward the rear side
of the machine where it is engaged by rod 54 de
70 pending to a suitable treadle or knee actuated
device (not shown), whereby the rod and arm 53
may be pulled downward to the limit of a stop
pin 55 against the tension of a coiled spring 56
surrounding the rod and normally tending to
hold the arm 53 up to the position in which it is
machine by a screw pivot 69, and carrying a screw
the upper end of a connecting bar 1| which latter
at its lower end pivots on the screw pivot 65
beneath the link 64. 12 is a buffer spring se
cured in a groove along the underside of the
hand lever 66 and adapted to contact with a
rod and at its other end bears in a short groove
along the upper edge of rock-arm 53. In the
normal position of the parts, the pressure of
spring 56 on the treadle rod 54 constantly tends
to move the parts to their normal position shown
in Fig. 1, where the rock-arm 53 contacts with
the screw stop 51 and the connecting rod ‘H is
elevated tilting the hand lever 66 forward with
its buffer spring 12 against stop screw 13. In
this position of the parts the axis of the pivot
screw 10 lies 'to the left of an imaginary straight
line connecting the axes of the pivot screws 65
and 69. To elevate the presser-foot by operation
of the hand lever 68 the latter is swung upward.
causing the pivot screw 10 to act against the
lower end of the wall of the slot in connecting bar
1| thereby imparting a longitudinal downward
and swinging movement to said rod and moving
it and the rock-arm 53, the arm 66 and link 64,
to positions in which the end of hand lever 68
contacts a pin 16 projecting from the end wall of (35
the machine head and in which position the axis
of the screw 16 will occupy a position slightly to
the right of an imaginary straight line connect
ing the axes of the pivot screws 65 and 69. In
this relationship of parts the upward pressure
exerted by spring 56 tends to hold the end of
lever 68 tightly in engagement with the pin 16
notwithstanding the weaker pressure of the
spring 14 tending to swing the upper end of the
connecting bar 1| toward the left. The parts
,
3
9,188,858
each side thereof. ‘As approx- 1
.are thus temporarily locked in position to hold a thicknesses ‘ at
imately shown, the side edge of the cross-seam
the feed roller elevated and will so remain until ' rises
almost vertically from the main body of
released by a slight forward and downward
movement of ie hand lewr il 01' asllght-d‘ownm
‘ward movement of the treadle connections, where
upon the parts will quickly snap back to ‘the
position in which they are illustrated in F18. 1.
The lifting of the feed roller,.either by actua
the fabric and presents ,aahump over which it
would be difficult for the feed roller to. lift it 5
self, with the result that it would rotate in the
corner or space immediately in front of the
cross-seam without feeding the work and would
thus mar or tear the surface of the fabric at
tion of a treadle or knee device (not shown). or >
this point. But with the assistance of the lifting
10 by actuation of the hand lever ‘I, also lifts the
presser foot by means which will now vbe' de
means of the present invention, the feed-roller
scribed. A second arm 11 (similar to arm 58)
forms its feeding function at normal feed speed.
extends toward ,the front of the machine from
the tubular rock-shaft BI and carries a block
15 (similar to block 59) which engages under a lug _
is assisted over such cross-:seams and also per
In Fig. 2 a ‘cross-seam formed in very heavy
fabric is shown as entering beneath the forward
end of the presser-foot and hastilted
(similar to lug I28 of Fig. 2, of the aforesaid upturned
the foot upward at said end withv the rear endv
Merritt Patent 1,837,468) or overhanging shoul . of
the foot resting on the main body'of the work.
der on the shank 3| of the presser-foot. Pref
At
the same time the upward tilting of :the
erably the parts are so positioned or related that presser-foot has elevated shank 3| and the press
20 the‘ arm 11 begins to lift the presser-foot just
er-foot bar 30 until the shoulder 82 on the shank
after the arm 88 begins to lift the feed roller; has
moved closer to the underside of the ‘arm 80. 1
but this may be changed as desired.
The construction as hereinbefore set forth in
the detailed description is, substantially the same
as that shown in the aforesaid Merritt patent,
except as to certain minor features which will be
Further feeding'movement of the cross-seam un
der the presser-foot engages the shoulder 82‘ ,
with arm 80 and thereby lifts said arm and with.v
it the bar 41 and feed roller 45 until saidroiler
apparent, and its operation is entirely satisfac- - bears upon the top of the cross-seam as shown in_ ~ \
tory for all ordinary conditions.
But extraordinary conditions, particularly as
30 to thickness of fabric or work passing under the
presser-foot, have been encountered in which it
has been found desirable to assist the operation
of the feed roller by slightly lifting the same in
addition to its own capabilityof elevating itself
in passing over humps or extra thicknesses of
fabric or work. For example, where a felled cross
seam passes through the felling folder 24 (Fig. 1)
and under the presser-foot and the fabric isof
average thickness, the feed roller, will ride up
over said cross seam, or'elevate itself, without
assistance. But if. the fabric is very thick, as
sometimes occurs, it has been found dimcult for
the feed roller, by its ownlaction, to ride up over
the hump formed by the cross-seam. In other
words, under such conditions‘it is desirable to
provide means to assist in lifting or elevating the
feed roller over the cross-seam and one embodi
ment of such means will now be described.
80 is a horizontal arm having an enlarged end
grooved transversely to fit about the lower end
of the presser-bar 41 for the feed roller, as clear
ly shown in Fig. 1.v A set screw 8i, passing
through a vertical slot in the enlarged end of
arm 80 and into bar M, rigidly securesv the arm
to said bar in any desired position of adjustment
within the limits of the length of the vertical
slot. When the fabric being sewed or operated
upon is of average thickness, the arm is secured
to the bar 41 with screw 8! passing through the
60 lower end of vertical slot, in which position of
the parts the arm does not function or is out of
action. But when the thickness of the fabric
exceeds the average, or the fabric is very thick,
the arm is secured to the bar 41 in a relatively
lower position, such as shown in the drawing, so
65
that the arm does function. At its other end
or outer end, the arm 80 overlies a shoulder or
70
offset 82 on the shank 3| of the presser-foot.
Figures 2, 3 and 4 showtwo sections of very
heavy or thick fabric being joined by a felled
seam, and with a felled cross-seam passing under
the presser-foot and feed roller. The fabric is
shown in vertical longitudinal section down the
middle of the seam, so that there are sixteen
75
thicknesses of fabric at the cross-seam and four
Fig; 3. As the feeding of the work and cross
seam continues, the presser-foot tilts downward
at its forward endyas shown in Fig. 4, and the 30
reverse of the aforesaid movements beginand
continue until the, cross-seam passes from be
neath the rear end of the presser-foot.‘
»
When the fabric is of a thickness which does
not require such lifting of the feed roller .by the 35
action of the presser-foot, the arm 80 is set on
the bar 41 to an inactive position. by loosening
set-screw-8l, sliding the arm 80 upward on bar.
d'l until the bottom of the slot‘in the‘ enlarged
end of the bar contacts the shank of said screw
and the screw then tightened to secure arm‘ 80 to
bar 41 in said inactive position.
What is claimed is:
’
'
.
1. A sewing machine including in combination,
a work support; a feed member downwardly and
yieldingly engaging work on said work support;
means for imparting feed movement to said feed
member; and means for lifting said feed member
in passing over thicknesses in the work such as
cross-seams.
.
2. A sewing machine including in combination,
50
a work support; a rotary feed member down
wardly and yieldingly engaging work on said
work support; means for imparting feed move
ment to said feed member; and means for lifting 55
said feed member in passing over thicknesses in
the work such as cross-seams.
3. A sewing machine including in combination,
a work support; a rotary feed member down
wardly and yieldingly engaging work on said 60
work support; means for imparting feed move
ment to said feed member; an upright bar mov
able up and down in a portion of the machine
above said work support and carrying said feed
member; and means for lifting said bar and with 05
it the feed member as the latter passes over
thicknesses in the work- such as cross-seams.‘
4. A sewing machine including in combination,
a work support; a feed member downwardly and
yieldingly engaging work on said work-support;
a presser foot downwardly and yieldingly engag-‘
ing said work on said work-support in advance
of its engagement by said feed-roller, said press- '
er-foot being supported to rock or tilt upwardly '
and downwardly at its forward end; means im
4
'
‘
2,128,858
parting feed movement to said feed member; and
means actuated by the rocking or tilting of the
presser foot to lift the feed member in passing
over thicknesses in the work such as cross-seams.‘
5. A sewing machine including in combination,
a work support; a feed member downwardly and
yieldingly engaging work on said work support;
a presser-foot downwardly and yieldingly engag
ing said work on said work-support in advance of
10 its engagement by said feed member; driving
means imparting feed movement to said feed
member; and means actuated by movement of
the presser foot in passing over thicknesses in the
work such as cross-seams to lift said feed mem
ber in passing over said thicknesses.
6. A sewing machine including in combination,
a work support; a rotary feed member down
wardly and yieldingly engaging work on said
work support; a presser-foot downwardly and
yieldingly engaging said work on said work-sup
port in advance of its engagement by said feed
member; driving means imparting feed move
ment to said feed member; and means actuated
by movement of the presser foot in passing over
25 thicknesses in the work such as cross-seams to
lift said feed member in passing over said thick
nesses.
“
'
7. A sewing machine including in combination,
a work arm having a free end off which work is
30
adapted to be fed; stitch-forming mechanism
positioned to operate on work advancing along
said arm toward the free end thereof; a top feed
member engaging work on and feeding the same
along said arm toward the free .end thereof;
driving connections for imparting feed movement
to said feed member in a direction to feed the
work along said arm toward the free end thereof;
and means actuated by thicknesses in the work
such as cross-seams to lift the feed member in
40 passing over said thicknesses in the work.
8. A sewing machine including in combination,
a work arm having a free end on’ which work
is adapted to be fed; stitch-forming mechanism
positioned to operate on work advancing along
said arm toward the free end thereof; a rotary
top feed member engaging work on and feeding
the same along said arm toward the free end
thereof; driving connections for imparting feed
movement to said feed member in a direction to
feed the work along said arm toward the free
end thereof; and means actuated by thicknesses
in the work such as cross-seams to lift the feed
member in passing over said thicknesses in the
work.
4.1
9. A sewing machine including in combination,
a work arm having a free end on’ which work is
adapted to be fed; stitch-forming mechanism
positioned to operateon work advancing along
said arm toward the free end thereof; a top feed
roller engaging work on and feeding the same
along said arm toward the free end thereof;
driving connections for imparting feed movement
to said feed roller in a direction to feed the work 20
along said arm toward the free end thereof; and
means actuated by thicknesses in the work such
as cross-seams to lift the feed roller in passing
over said thicknesses in the work.
10. A sewing machine-including in combina
tion, a work support; a top feed member down
wardly engaging and feeding the work along said
work support; a bottom feed member upwardly
engaging and feeding the work along said work
support; means for imparting feed movement to '
said top and bottom feed members; and means
for lifting said top feed member in passing over
thicknesses in the work such as cross-seams.
11. A sewing machine including in combination,
a work support; a rotary top feed member down
wardly engaging and feeding the work along said
work support; a bottom feed member upwardly
engaging and feeding the work along said work
support; means for imparting feed movement to
said top and bottom feed members; and means
for lifting said top feed member in passing over 110
thicknesses in the work such as cross-seams.
CHARLES W. DOWD.
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