close

Вход

Забыли?

вход по аккаунту

?

код для вставки
Dec. 24, 1946. _
F, F‘ ZEER
'
'
2,413,277
THREAD CONTROLLiNG MEANS FOR SEWING MACHINES
Filed May 14, 1945
@311
E .
oyredericé C7 jea'er
‘$91,161,056:
-
'
W
2,413,277
Patented Dec. 24, 1946
UNITED STATES
OFFICE
2,413,277
THREAD CONTROLLING MEANS FOR
SEWING MACHINES
Frederick ‘F. Zeier, Strat?eld, Conn., assignor to
The Singer Manufacturing Company, Eliza
beth, N. J ., a corporation of New Jersey
Application May 14, 1945,'Serial No. 593,679
16 Claims. (0]. 112-255)
1
2
invention is disclosed as embodied in a sewing
This invention relates to thread controlling
machine having a frame including a work-sup
meansfor sewing machines and more particularly
portl, a bracket-arm 2, terminating in a bracket
to intermittent thread tensions for sewing ma
arm head3 in which is mounted for reciprocation,
chines such, for example, as disclosed in United
States Patent No. 2,329,681, Sept. 14, 1943.
CI. aneedle-bar 4. At its lower end, the needle-bar
carries two eye-pointed needles 5, with which co
In sewing canvas, denim and other heavy
operate conventional loop-takers (not shown) in
and/0r hard ?nish materials, it is essential that
the formation of stitches. The needle-bar is re
a very heavy tension be applied to the- thread
ciprocated from a rotary shaft 6 journaled length
during the ?nal tightening of the stitch by the
thread take-up mechanism, otherwise thread 10 wise in the arm 2 by mechanism designated gen
erally as T; A needle-thread take-up device (not
will be stolen from thesupply and the stitch will
shown) also is located in the bracket-arm head
not be completely set. The tension required at
and isactuated from the arm shaft 6. This take
that instant is greater than that required during
up device is disclosed in the above noted United
other portions of the stitch-forming cycle and
therefore it has become the practice to provide, in 15 State Patent No. 2,329,681, Sept. 14, 1943.
Mounted on the upper portion of the arm 2 are ~
heavy duty machines, a thread tension device,
two‘lthre'ad tension devices 8 each of which is
supplementary to the main thread tension, which
adapted to apply a constant tension on one of
is rendered effective only at the critical time
twoneedle threads 9 which are directed through
during the tightening of the stitch.
The primary object of this invention is to pro 20 thread. guides I0 and H to the needle-thread
take-up device in the bracket-arm head. ‘
vide an improved form of intermittent thread
The improved intermittent‘ thread tension,
tension device which is easy to assemble and ad
designated generally as I2 in Fig. 1, is located in
just and in which means are provided for varying
termediate the constant thread ‘tensions 8 and the
(a) the degree of tension applied to the thread;
(17) the instant in the stitch tightening cycle at 25 thread guide I!) and is actuated by an eccentric l3
secured upon the shaft 6 by set screw Hi. This
which the intermittent tension becomes eifective;
device comprises a, supporting bushing l5 fitted
and (c) the duration of applied tension.
Within a counterboard aperture l6 provided in the
With the above and other objects in View, as
wall of the bracket-arm 2 and is formed with a
will hereinafter appear. the invention comprises
the devices, combinations and arrangements of 30 collar portion l5,a and a reduced outwardly ex
tending threaded portion It". The bushing 15
parts hereinafter set forth and illustrated in the
is heldlin the aperture l6 by' a combined clamp
accompanying drawing of a. preferred embodi
plate and thread-guide member ll, which, as
ment of the invention, from which the several
shown most clearly in Fig. 5, is made of sheet
features of the invention and the advantages at
metal and hasv a central aperture ll’a through
tained thereby will be readily understood by
which? the threaded portion 15b of the bushing
those skilled in the art.
passes. The member I1 is provided with per
In the drawing,
Fig. 1 is a side elevation of a portion of a sewing
forated ears l8 and laterally off-set bifurcated
arms l9. Screws 20, passing through the aper
Fig. 2 is an enlarged horizontal sectional view 40 tures in the ears l8 and threaded into tapped
taken substantially on the line 2—-2 of Fig. 1,
ho1es~2l in the arm 2, draw the plate i1 into con
showing the intermittent tension device in re
tact wit-hthe outer face of the collar portion We
leased or ineifective position.
of vthe bushing and'force the inner face of the col
Fig. 3 is a View similar to Fig. 2 but with cer
lar into contact with the arm 2, thereby holding
tain of the parts in elevation and with the inter
the .member ll against movement. Slots 22
mittent tension device shown in thread engaging
formed in‘ the arms I9 serve as guides for
position.
the‘threads £9 passing to and from the inter
Fig. 4 is a sectional view taken substantially on
mittent
tension.
the line 4-4 of Fig. 2 showing, in full and in dot
‘ 'Slidingly mounted in a bore 15° in the bushing
ted lines, the time control element of the device
I5 is a plunger 23, the inner end of which is
‘in two positions of adjustment.
pivoted,
at 24, to a strap 25 which surrounds the
Fig. 5 is a disassembled perspective view of
eccentric l3. Rotation of the shaft 6, and. the
three of the principal elements of the improved
eccentric l3 thereon. causes the plunger 23 and
tension device, later to be described.
Referring more speci?cally to the drawing, the 55 parts carried thereby to be reciprocated in the
machine embodying the present invention.
2,413,277
4
3
bushing |5 for a purpose hereinafter to be ex
the clamping or tensioning period is relatively
plained.
small.
When the collar 26 is adjusted outwardly on the
plunger 23 to the position shown in dotted lines
Threaded upon the portion |5b of the collar l5,
outside the member I1, is a stop collar 26 which
affords a ?xed, but adjustable, abutment for one
of two relatively shiftable tension disks, as later
will be described. . This collar is split circumfer
in Fig. 4, the space between the tension disks is
reduced. Therefore, upon inward movement of
the member 38 and disk 32, the threads are
entially, as at 21, thus affording relatively yielda
clamped more quickly and remain clamped ma
terially longer than when the collar is in the po
through the wall 28, has its inner end bearing 10 sition shown in full lines. Thus it will be appar
against the wall 29, whereby rotation .of the
ent. that this construction affords means for
varying the time in the stitch forming cycle at
screw tends to distort one or both of the walls 28
and 29 thus causing the threads in the collar 26
which the intermittent tension becomes effective
and also the' length of time during which the
to bind on the threads on the portion |5b of the
ble walls 28 and 29.
A screw 30, threaded
bushing l5, thereby preventing accidental rota
tion of the collar on the bushing. Thus the collar
26 may be held in various positions of adjust
ment on the bushing.
Rotatably journaled on
the plunger 23, outside the collar 26, is a pair of
tension disks 3|, 32 between which pass the
needle threads 9.
The plunger 23 is provided with an axial bore
33 into the outer end of which is threaded a plug
or abutment block 34. Slidingly mounted in the
bore 33 is the head 353 of a rod 35. The outer
tension remains effective.
By adjusting the nut 36 on the rod 35, the
' head 35a may be adjusted toward or from the
abutment block 34, thus varying the compression
of the spring 40. It will be understood that the
more the spring is compressed the more rigid it
will be and therefore the more positive will be
the clamping of the threads between the two ten
sion disks. Adjustment of the nut 36 in the op
posite direction has the opposite effect. There
fore, this construction also provides means for
end portion of the rod passes freely through an
aperture in the plug 34 and has threaded thereon
an adjusting nut 36 and a lock nut 31.
Fitted upon the rod 35, intermediate the outer
end of the plunger 23 and the adjusting nut 36,
is a cup-like presser member 38 of which the in
ner circular edge bears against a washer 39 which,
in turn, is adapted to bear against the outer ten
sion disk 32.
A coil spring iii), surrounding the rod 35 in the
bore 33, has one end in contact with the rod head
358L and its other end in contact with the ?xed
abutment block 34. The spring 40 is under com
pression at all times and therefore tends to draw
the rod 35, nut 36 and member 38 inwardly until 40
member mounted on said bushing, a plunger re
the base of the member 38 engages the outer en
ciprocally supported by said bushing, a pair of
of the plunger 23, as shown in Fig. 2.
opposed tension disks mounted on said plunger, a
?rst one of said disks engaging said abutment
member, a yieldable thrust member carried by
'
'
As above stated, rotation of the shaft 6, and
the eccentric |'3 thereon, effects endwise recipro- _
cation of the plunger 23 and the parts carried
thereby. Rotation of the eccentric away from
the position shown in Figs. 2 and 4 causes the
plunger 23, and the parts'carried thereby, .to be
drawn inwardly. Inward movement of the parts
shifts the outer tension disk 32 into clamping
contact with the thread, or threads, passing >be—
tween the two tension disks; the inner ‘disk ‘3|
being held against inward movement by its con
tact with the stop collar 26. Inasmuch‘ as the _
throw of the eccentric I3 is greater than the space
between the tension disks, it follows that after ‘in
ward movement of the outer disk 32,‘ member’38
and rod 35 have been arrested,‘ continued rotation
of the eccentric will draw the plunger 23 and plug
34 inwardly away from the base of the member 60
38, as shown in Fig. 3.
This compresses the
spring 40 and clamps the threads between the
tension disks 3| and 32 thus producing the de
sired tensioning effect on the threads.
A
varying the degree of tension applied to the
thread.
It will be apparent that the adjustment which
controls the time and duration of the clamping
effect is wholly separate from and independent of
the adjustment which controls the degree of ten
sion applied to the threads and that, therefore.
either adjustment may be made independently
of the other.
Having thus set forth the nature of the in
vention, what I claim herein is:
‘
‘
1. In a sewing machine having a frame; an
intermittent thread tension device comprising a
bushing carried by said frame, an abutment
said
said
into
and
plunger and adapted by axial
plunger to force the second
thread-clamping contact with
means for reciprocating. said
movement of
of said disks
the ?rstdisk,
plunger dur
ing each stitch-forming cycle.
2. An intermittent thread tension device as
set forth in claim 1, including means for varying
the time of application of said tension, means
for varying the degree of tension‘ applied to the
thread, and means for varying the duration of
the applied tension.
3. In a sewing machine having a frame pro
vided with an aperture and a rotary shaft jour
naled in said frame; anintermittent thread ten
sion device comprising a bushing ?tted, into the
aperture in said frame, and provided With'a re
duced extension, a plate surrounding said Vcx~
tension and bearing against said, bushing to main
tain it in said aperture, an abutment member
mounted on the reducedextensiontof said bush
The time at which the disks 3|, 32 become ef
fective to grip the thread and the duration of the
tensioning effect are dependent upon the lost mo
ing, a plunger reciprocally mounted in said'bush
tion between the disk 3| and the movable disk 32.
Thus, with the stop collar 26 adjusted to the po
sition shown in full lines in Fig. 4, the spacebe
said abutment member, a yieldablethrust mem~
ber carried by said plunger and adapted by axial
ing, a pair of opposed tension disks’mounted on
said plunger, a ?rst one of said disks engaging
movement of said plunger to force the second of
said disks into thread-clamping contact‘ with the
tween the tension disks 3| and 32 is considerable
and therefore the gripping of the threads there
between will be delayed until the eccentric‘ |3 has
reciprocating said plunger.
made the major portion of'its rotation. Likewise
with the parts in this position, the duration of
4. In a sewing machine having a frame; an in
termittent thread tension device comprising a
?rst disk, and means actuated by said shaft for
'.
,
'
"
2,413,277
6
bushing carried by said frame, an abutment mem
ber‘ adjustably mounted on said bushing, a
plunger reciprocally mounted in said bushing, a
pair of opposed tension disks mounted on said‘
plunger, a ?rst one of said disks engaging said
abutment member, a yieldable thrust member
carried by said plunger and adapted ‘by axial
movement of said plunger to force the second ‘of
thread tension device comprising a bushin'g.car—
ried‘by said frame, an abutment'member mounted
on said bushing, a plunger reciprocally mounted
in said bushing and having an axial vbore‘, a plug
in the‘ outer end of said bore having a central
aperture, inner and outer tension disks mounted
on said plunger, the inner disk engaging said
abutment member, a rod extending through the
said disks into thread-clamping contact with the
aperture in said plug and having a head portion
?rst disk, means for adjusting said abutment 10 in the bore in said plunger, a coil spring sur-"
member on said bushing to vary the time and
rounding said rod and having one end bearing
duration of the thread-clamping action of said
on said head and its other end bearing on said
disks, and means for reciprocating said plunger.
plug and urging said rod inwardly, a pressure
5. In a sewing machine having a frame pro
member surrounding the outer end of said plung
vided with an aperture and a rotary shaft jour 15 er and operatively connected with said rod, and
naled in said frame; an intermittent thread ten
means actuated by said shaft for reciprocating
sion device comprising a bushing ?tted into the
said plunger and the rod therein to cause said
aperture in said frame and provided with a re
duced extension; a plate surrounding said ex
tension and bearing against said bushing to main
tain it in said aperture, said plate being provided
with a plurality of perforated ears and a pair of
laterally off-set arms affording spaced thread
guides, screws passing through said perforated
ears and threaded into said frame to secure said
plate thereto, an abutment member mounted on
the reduced extension of said bushing, a plunger
pressure member to apply pressure on the outer
of said tension disks to force it into thread
20 clamping contact with said inner disk.
9. An intermittent thread tension as set forth
in claim 8 in which means is provided for vary
ing the compression of the coil spring in said
plunger thereby to vary the pressure capable of
being transmitted to said tension disks by said
pressure member.
10. In a sewing machine, an intermittently ac
tuated thread tension device operative during
each stitch-forming cycle, including a pair of
a ?rst one of said disks engaging said abutment 30 opposed tension disks, means operative periodi
cally for urging said disks together to grip a
member, a yieldable thrust member carried by
said plunger and adapted by axial movement of
thread passing therebetween, means for varying
the time in the stitch-forming cycle at which
said plunger to force the second of said disks into
tension is applied to the thread, means for vary
thread-clamping contact with the ?rst disk, and
means actuated by said shaft for reciprocating 35 ing the degree of tension applied to the thread,
reciprocally mounted in said bushing, a, .pair of
opposed tension disks mounted on said plunger,
said plunger.
6. In a sewing machine having a frame and a
rotary shaft journaled therein; an intermittent
thread tension device comprising a bushing car
ried by said frame, an abutment collar threaded
on said bushing, a plunger reciprocally mounted
in said bushing, a pair of opposed tension disks
and means for varying the duration of the ap
plied tension.
11. A sewing machine intermittent tension de
vice including an outer member, a plunger recip
rocally mounted in said outer member, means
for reciprocating said plunger during each stitch
forming cycle, a pair of thread tension disks
mounted on said plunger, and tension varying
means carried by said plunger accessible from
engaging said abutment collar, a yieldable thrust
member carried by said plunger and adapted by 45 one end thereof for regulating the degree of ten
sion applied to thread passing between said disks.
axial movement of said plunger to force the sec
12. A sewing machine intermittent tension de
ond of said disks into thread-clamping contact
vice including an outer member, a plunger recip
with the ?rst disk, means for adjusting said collar
axially of said bushing to vary the thread-clamp
rocally mounted in said outer member and hav
ing an axial bore, means for reciprocating said
ing action of said disks; and means actuated by .
plunger during each stitch-forming cycle, a pair
said shaft for reciprocating said plunger.
7. In a sewing machine having a frame and
of thread tension disks mounted on said plunger,
and tension varying means located mainly with
a rotary shaft journaled therein; an intermittent
thread tension device comprising a bushing car
in said bore and accessible from one end of said
ried by said frame and/having a reduced ex
plunger for regulating the degree of tension ap
tension, a split abutment collar mounted on the
plied to thread passing between said disks.
extension of said bushing, a plunger reciprocally
13. A sewing machine intermittent tension de
mounted in said bushing, a pair of opposed ten-i
vice including a pair of thread-engaging tension
sion disks mounted on said plunger, a ?rst one
disks, means for supporting said disks, means op
erative periodically for urging said tension disks
of said disks engaging said abutment collar, a
mounted on said plunger, a first one of said disks
yieldable thrust member carried by said plunger
and adapted by axial movement of said plunger
into thread-engaging relation, and regulatable
means effective to vary the time of engagement
to force the second of said disks into thread
of said disks with the thread and to vary the
duration of the applied tension on the thread.
clamping contact with the ?rst disk, means in
cluding complemental threads on said bushing 65
14. A sewing machine intermittent tension de
vice including a pair of thread tension disks,
and in said collar for adjusting said collar axi
ally of said bushing to vary the thread-clamping
means for supporting said disks, means opera
tive periodically for urging said tension disks
action of said disks, means for de?ecting one por
into thread-engaging relation, and regulatable
tion of said collar relative to another portion
means including a threadedly mounted abutment
thereof to cause it to bind on the threads of said
effective for varying the time of engagement of
bushing thereby to maintain said collar in its ad
justed position, and means actuated by said shaft
said disks with the thread and for varying the
for reciprocating said plunger.
duration of the applied tension on the thread.
15. An intermittent tension device for sewing
8. In a sewing machine having a frame and
a rotary shaft journaled therein; an intermittent 75 machines, comprising, opposed tension-disks sup
2,413,277
ported for relative axial movement, an endwise
reciprocatory member having a ?xed amplitude
of reciprocation, means 'for reciprocating said
member during each stitch-forming cycle, means
yieldingly vcarried by and movable bodily with
said member for relatively moving said disks into
thread-tensioning position, and means for vary
ing the degree of tension imposed on the thread.
16. An intermittent tension device for sewing
machines, comprising, opposed tension-disks sup- 10
8
ported for relative axial movement, an endwise
reciprocatory member having a ?xed amplitude
of , reciprocation, means for reciprocating said
member, means yieldingly carried by said member
for relatively moving said disks into thread-ten
sioning position, and means for varying the ten
sion application time and the tension duration
time.
FREDERICK F. ZEIER.
Документ
Категория
Без категории
Просмотров
0
Размер файла
633 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа