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Патент USA US2857878

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Oct. 28, 1958
D. BAUM
2,857,868
METHOD FOR POSITIONING A SEWING MACHINE NEEDLE
Filed Dec. 10, 1953
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4:’- E
INVENTOR
0/! W0 BA UM
BY ‘\3 - 15-.
AT
NEY
Unite
atent 0 M1C6
2,857,868
Patented Oct. 28, 1958
2
Fig. 5 is the same as Fig. 3 and illustrates the third
or de?ecting phase of the sewing cycle, and
Fig. 6 is the same as Fig. 3 and illustrates the ?nal
or withdrawal phase of the sewing cycle.
2,857,868
Referring now to Figs. '5 to 6 of the drawing, I have
shown the device of the present invention ‘applied to a
conventional Union Special sewing machine which com
prises a needle "I threadedly engaged at 8 to a needle
METHOD FOR POSITIONING A SEWING
MACHINE NEEDLE
David Baum, Livermore Falls, Maine
Application December 10, 1953, Serial No. 397,438
3 Claims. (Cl. 112‘—-227)
bar 9. ‘Functioning synchronously with the operation of
needle 7 are a thread‘looper ill, a presser foot 11 and a
feed dog 12 between the latter two of which the work
to he sewed is fed. Presser foot 11‘ is secured in con
ventional manner to a presser arm 13 while feed dog
12 is secured to shank 14. Shank i4 is. connected to,
This invention relates to a method and apparatus for 15 and movable with, feed bar 15. Adjacent feed dog 12
positioning a sewing machine needle to prevent de?ection
is a throat plate support 16 which is secured to a station
thereof under stress exerted by the operator.
ary part of the machine by member 17.
Slidably mounted between guides 18, mounted on one
face of shank lid, is a mounting plate 19. Plate 19 is
the operators to push or pull the work through the 20 vertically adjustable by means of an adjustment screw
machine, which tendency has no deleterious effect on the
20 and nut 21, the former of which is threadedly engaged
needle so long as the work is ?rmly held between the feed
with a sleeve 22 secured to shank l4. Adjustably mounted
dog and presser foot of the machine. However, during
on plate 19 by means of a set screw 23 is a needle de
that portion of the sewing cycle when the feed dog drops
ilector 24 which may be L-shaped. As indicated at 25‘,
below the level of the throat plate out of engagement 25 one arm of de?ector 24 is centrally slotted from one
with the work and the point of the needle has passed
terminus to a point beyond its midpoint, for the reception
through the work, any pushing or pulling of the work
of set screw 23, thereby permitting horizontal adjustment
' will exert a stress on the needle causing the latter to spring
of de?ector 24. Thus de?ector 24’, may be horizontally
or bend. If the force applied to the needle is very great,
and vertically adjusted to accommodate di?erent sized
it will snap the needle in two. Even in the case where
needles and effect any desired ?exing of needle ‘7.
the needle is not sprung to the point of snapping, the
in operation, needle '7 is initially in the position shown
de?ection of the needle changes the relative positions
in Pig. 3, at which time presser foot 11 and feed dog
of the needle and the thread looper, resulting in “skipping”
i2 engage the work. The needle then passes through
or breaking of the thread, thereby producing an inferior
the work to the position shown in Pig. 4. Presser foot
35 Ill and feed dog 12 continue to grip the work, thereby
sewing job.
It is an object of this invention, therefore, to provide
preventing any movement of the work and consequent
a method for ?exing the needle of the sewing machine
bending of needle 7 under stress by the operator. Needle
a predetermined distance during that portion of the sew
7 continues its downward stroke to the lowermost point
ing cycle when the feed dog is disengaged from the work,
in its cycle, shown in Fig. 5, at which‘ time feed dog 12
and prior to the exertion of stress on the needle by 40 is disengaged from the work for the ?rst time. it is at
the operator, thereby preventing further springing of the
this point in the cycle that needle de?ector
operating
needle when the work is pushed or pulled through the
synchronously with feed dog 12, moves laterally into
machine and maintaining at all times the correct position
engagement with needle 7, springing the latter a predeter
of the needle with respect to the‘ thread looper.
mined amount. Since presser foot Ill and feed dog 12
Another object of this invention is to provide a sewing 45 no longer prevent movement of the work under urging
machine attachment for ?exing or springing the sewing
of the operator, any pulling or pushing force on the work
machine needle during a portion of the sewing cycle, the
will be transmitted to needle “7. However, needle de?ec
movement of which attachment is synchronized with
tor 24 positively precludes the movement of needle 7 in
the operation of the other moving components of the
the direction of shank M and, by springing needle 7
machine.
in the direction opposite shank 14-, to a degree approach
A further object of the invention is to provide a
ing the elastic limit of the needle, the latter is able to
sewing machine attachment for ?exing or springing the
withstand any lateral stress that may be exerted on it by
sewing machine needle, which attachment may be readily
the work. Experiment has shown that optimum results
attached to the machine and is easily adjustable both in
are obtained ‘when the needle is de?ectedjapproximately
55 one-sixteenth of an inch. As the needle ascends, it en~
the vertical and horizontal directions.
The invention, together with its objects and advantages,
gages thread looper ill which is so adjusted to engage
will be best understood by reading the following detailed
the needle while the latter is in the de?ected position.
description with reference to the accompanying drawing
in Fig. 6 there is shown the Withdrawal. phase of the
in which is illustrated a presently preferred embodiment
cycle in which needle 7 rises out of engagement with
60 needle de?ector 24 and feed dog 12 reengages the work
of the invention, and wherein:
Fig. 1 is a perspective view of the sewing machine at~
to once again retain the latter against movement under
tachment forming a part of the present invention;
force exerted thereon by the operator.
Fig. 2 is a similar view of the same, looking at the
While the present invention has been shown and de
front of the de?ector;
scribed in connection with a Union Special sewing ma
Fig. 3 is a fragmentary side elevational view of a 65 chine, it is to be understood that such has been done for
sewing machine illustrating the application of the present
purposes of illustration only and not by way of limitation,
device and showing the initial position assumed by the
and therefore only such limitations are to be imposed
in the use of numerous types of sewing machines it
has been found that there is a tendency on the part of
moving components of the machine, the throat plate and
thereon as may reasonably come within the scope of the
appended claims.
work support being removed to disclose details of struc
ture;
Fig. 4 is the same as Fig. 3 and illustrates the second
or work-engaging phase of the sewing cycle;
70
What I claim is:
1. A method for positioning a sewing machine needle
to prevent de?ection thereof under stress exerted on the
2,857,868
3
Work by the operator, comprising the steps of springing
the needle a predetermined amount in the plane of stress
exerted on the needle by the ‘work, when the feed dog of
the machine drops out of engagement with the work, and
releasing the needle when the feed dog re-engages the
work.
2. A method for positioning a sewing machine needle
to prevent de?ection thereof under stress exerted on the
work by the operator, comprising the steps of springing
4
ing stress exerted on the work by the operator, compris
ing the steps of springing the needle in the direction
exerted thereon by the pulling stress when the feed dog
of the machine drops out of engagement with the work,
locating the thread looper to take the needle loop when
the needle is in the sprung position, and releasing the
needle when the feed dog re-engages the work.
References Cited in the ?le of this patent
the needle in the plane of stress exerted on the needle 1O
by the work to a point approximating the elastic limit
of the needle, when the feed dog of the machine drops
out of engagement with the work, and releasing the needle
when the feed dog re~engages the work.
'
3. A method for positioning a sewing machine needle 15
to prevent de?ection thereof under the pushing and pull~
UNITED STATES PATENTS
657,400
898,403
934,954
1,134,528
2,496,243
Dimond et al. ________ __ Sept. 4,
Corey ______________ __ Sept. 8,
Woodward __________ __ Sept. 21,
Hansen ______________ __ Apr. 6,
Clayton ____________ __ Jan. 31,
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