US1532535A - Sewing machine - Google Patents

Description

April 7, 1925.

1,532,535 G. J. KILIGAS v SEWING MACHINE Filed Dec. 9, 1921 IN VEN TOR Mb w vw A TTORNE Y5.

?atented Apr. 7, 1925.

- 1,532,535 PATENT OFFICE.

GUSTAV J. KILIGAS, OE BROOKLYN, NEW YORK.

SEWING MACHINE.

Application filed December 9, 1921. Ser al No. 521,078.

To all whom it may concern:

Be it known that I, GUSTAV J. KILIGAS, a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Sewing Machines, of which the following is a full. clear, and exact description.

This invention relates to sewing machines, and more especially to the thread take-up devices therefor. Particularly on sewing machines employing a looper, means must be provided to take up and maintain the proper tautness of the thread during the movements of the looper, and one of theicommon expedients for this purpose isa rotary takeup cam on the main or cam shaft cooperating with a stationary take-up and cast-off wire. The main shaft rotates at a high rate of speed and when the thread breaks, as frequently happens, it is likely to be wound around the shaft and becomeentangled in the take-up mechanism before the machine can be stopped. Considerable time is then necessary to untangle the thread, and

thread the take-up device and looper before the machine can again be operated.

The purpose of this invention is to provide an improved take-up mechanism for the looper thread of sewing machines w1th which breakages of the thread are lessened,

with which entangling of the thread with the mechanism is prevented when a breakage does occur, which can be quickly and easily rethreaded when a breakage occurs,

- which maintains the proper tautness of the looper thread during all the movements of the looper, which has a minimum of parts, which can be quickly and easily attached to present machinesdwithout any radical changesin their construction, and which is durable and effective in use and simple and inexpensive in construction. Other objects and advantages will be apparent from the following description and the novel features of the invention will be particularly pointed out in claims. 7 w

In the practice of the invention, I contemplate providing athread guidethrough which the thread passes directly to the looper movable with the looper operating rod, so that the guide will move simultaneously in the same directions with the looper. Upon the frame if the machine and between the guide and the looper, Iplace a second or stationary guide. through which the In the illustrated embodiment, a suitable frame 1 is provided for supporting the operative parts of the mechanism. A needle holder 2 carrying a. needle 3 is mounted for reciprocationon the frame 1. A bell crank lever 4 is pivoted to the frame at 5 and has an arm 6 pivotally connected by a link 7 to :1 lug 8 carried by the needle holder 2, whereby when the bell crank lever is: oscillated the needle holder and needle will he reciprocated. A main or cam shaft 9 passes through the base of the frame and is continuously driven from any suit-able source of power through a pulley 10. The shaft 9 carries an eccentric 11 which operates an cecentric rod12 that is connected to an arm 13 of the bell crank lever 4, so that as the shaft 9 is rotated through the medium of the pulley 10, the bell crank lever 4 will be. oscillated about its pivot 5. A U-shape frame 14 is pivoted at the ends of its arms to and between spaced uprights 15 and 16 on the base of the frame, the pivots of the frame l i'being parallel with the shaft 9. A looper arm 17 is pivoted at one end to the intermediate part-of the frame 14 by a pivot 18 and at its upperend carries a looper nose 19 having spaced apertures 20 therein I through which the thread is passed. A. connecting link or element 21 ispivotally connected at 22 to the looper arm 17 at a point between the looper nose and the pivot 18, so that-the connecting link and looper nose will move simultaneously in the same direction and at the same time. The looper arm partakes of a swinging movement with frame 14 to the upright 16 comprises a shaft 24 which is afiiK-ed to the frame and rotates in a. bearing in the upright- 16 and also in a bearing in another spaced upright 25. The portion of the shaft'24e between the up rights 16 and 25*is provided with a forked arm 6 ai'iixed thereon and embracing the opposite sides of an eccentric cam 27 on the main shaft 9, so that as the shaft 9 rotates the eccentric cam 27 will oscillate the frame Li and impart to the looper a movement transverse to the reciprocations of the needle.

The needle thread (not shown) is conducted through a tension device 23. to a loop 29 on the frai'ne 1, then through a loop 30 on the arm 6 of the bell crank lever at, thence to loop 31 upon the needle holder and then through the usual eye of the needle 3. The looper thread 32 is conducted through a tension device similar to tension device 28 and carried by the frame 1, but hidden by device 28 in Figure 1, then through a small aperture 33 in the frame 1, then over a guide 3% carried by the frame 1 between the aperture 33 and the looper. The looper thread in leaving the guide 34 passes in a direction away-from the looper and over a guide 35 carried by the connecting link 21 at its point of. connection to the arm 23 of the bell crank lever l, and then is carried directly to the looper and passes through the apertures 20 thereof. The attachment of the guide 35 to the connecting link is conveniently accomplished by providing the guide with an eye 36 through which is passed the pivot .bolt 37'by which the link is secured to the arm 23.

Int-he formation of the single needle double thread stitch, the needle carried its the fabric forward, the looper is rocked by the cam 27 across the path of the needle and then returns toward the right forming av triangular spacebetween the back of the looper, the looper thread on the left and the needle thread on the rightinto which the needle descends with its thread. The looper continuing to return toward the right leaves the stitch on the needle. As the needle again ascends the stitch is released from the needle and tightened in the fabric'by the action of the looper as it forms the next stitch.

During the movement of the looper it is desirable. that the looper thread be maintained in a sufficiently taut condition to avoid loose movement of the looper thread with the looper, since the arc of movement of the looper nose is greater than the are of movement of the guide 35. When the looper begins its movement to the right, the guide 35 also moves to the right and prevents slack ness in the thread between the looper nose and this guide and because of the fact that the guide 35 is moving away from the guide 34, the looper thread will be pulled through its tension device, through aperture 33 and Over the guide 34, so that enough thread is brought through the tension device in this movement to provide for the next movement of the looper. The slackness in the looper thread between the guides 34 and 35 during the forward movement of the looper permits the movement of the looper thread freely through the apertures 20 of the looper nose as the fabric is carried-forward.

WVith this arrangement, it will be seen i that the looper thread is taken up andreleased at the propertimes and that the thread is pulled through the tension device during the return movement of the looper. With the mere addition of the guides 34 and 35 to the'frame in the positions illustrated and described and with the addition of the aperture 33, the take-up and let-off operations are efficiently accomplished and the use of the more complex and troublesome takeup and let-off mechanism heretofore provided upon the rotary shaft!) is eliminated.

It will be understood that the embodiment herein described and illustrated is for; the purpose of explanation only, and that various changeslin the details and arrangements may be made by those skilled in the art within the principle and scope ofthe invention.

I claim: 7

1. In a sewing machine a frame,a=recip rocating needle, a 'looper,'meansfor reciprocating the needle, a link connected to said looper to operate-the same and in turn reciprocated by said means in timed relation to the movement of the needle, a thread guide through which the thread passes to the looper movable with said ,link, a stationary thread guide through which the thread passes to the first guide, said staionary guide beingdisposed between the first guide and. the looper, --said :frame' having a third guide for directing the thread to the stationary guide and located further from the looper than the stationary guide but in the same direction.

2. In a sewing machine having a frame, a reciprocating needle, a looper, and means including a link for operating the looper in timed relation to the movement of the needle, a thread guide through which the thread passes to the looper movable with the link, a second guide through which the thread passes to the first guide, said second guide being stationary and disposed be tween the first guide and the looper, and means for conducting a thread under ten sion to said second guide in a direction towards the looper.

3. In a sewing machine, a frame, a pivoted arm carrying a looper nose, an element for oscillating the arm connected to the nose carrying side of the pivot thereof, whereby the element and looper nose move simultaneously in the same directions, a thread guide through which the thread passes to the looper nose, said guide being movable with said element, a second thread guide through which the thread passes to the first guide, said second guide being stationary and disposed between the first guide and the looper nose, and means for supplying a thread to said second guide and retarding its movement.

' i. In a sewing machine, a frame, an arm carrying a looper nose, an element for operating the arm whereby the element and looper nose move simultaneously in the same d rections, a thread guide through which the thread passes to the looper nose, said guide being movable with said element, a second thread guide through which the thread passes to the first guide, said second guide being stationary and disposed between the first guide and the looper nose, said frame having an aperture for guiding the thread to said second guide, the aperture being located at a further distance from the looper arm than the second guide and in the same direction, and a device for frictionally retarding movement of the thread to said aperture.

In witness whereof I hereunto subscribe my signature.

GUSTAV J. KILIGAS.

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