US1454500A - Stitch-forming mechanism for sewing machines - Google Patents

Description

May 8, 1923.

E. B. ALLEN STITCH FORMING MECHANISM FOR SEWING MACHINES Filed Feb. 18, 1922 \WENTOR ATTORNEY WITNESSES: v

Patented May 8, 1923.

FACTURING COMPANY, or JERSEY. a

STITCH-FORMING MECHANISM Fen SEWING-'MAGHINES. v

Application filed February 18,1922. Serial No. 537,382.

To aZZwZzom it'mag concern."

Be it known that I, EDWARD B. ALLEN, a citizen of the United States, residing at Newtown, in the county of F airfield and State of Connecticut, have invented certain new and useful Improvements in Stitch-Forming l\/Iechanisms for Sewing Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to overseaming stitch-forming mechanism more particularly of the type disclosed in the patent to Allen et al., N o. 1,372,st73, March 22, 1 921,

and adapted for buttonhole sewing. The

invention has for an object to provide the stitch-forming mechanism with means facilitating the setting of the purl close to the edge of the seam or, when sewing buttonholes, close to' the buttonhole slit. I

In stitch-forming mechanism of thecharacter under consideration, the concatenation of-the looper-thread with the needle-loops forms the purl and, in accordance with the present improvement a device is interposed between the looper and the "work for holding the looper-thread leading from the looper to the last stitch in'an elevated or more nearly horizontal position than heretofore, so that when the looper is retracted. to tighten the looper-loop, such loop willbe set over close to the buttonhole-slit without straining or-distending the previous needle loop. The purl or line of the interlocked needle and looper-threadloops willthus' be set over close to the buttonhole-slit.'

In the accompanying drawings, Fig. lis a front elevation of stitch-forming devices embodying the present improvement. Fig. 2 is a left side elevation of the same. Fig. 3 is a right side elevation of one of the loop detaining elements shown in Figs. 1 and 2 and Fig. 4 is a fragmentary View similar to Fig.2 but at a later stage in the stitch-forming cycle.

In the specific embodiment of the invention chosen for the purposes of the presentdisclosure 1 represents the reciprocating and laterally jogging needle of the well known type disclosed in said Allen et al.. patent. The needle 1 is so actuated as to pass alternately through the buttonhole-slit 2 in the Work 3 and at a distance from such slit. The work 3 is held clamped by the lower worksupporting plates '4: and upper clamping feet 5 of a suitable machine such as that dis closed in my Patent No. 1,372,472, of March 22, 1921'.

EDWARD B; A-IlLENyOF NEWTOWN, oom acrrounnssrenon r'o rr-IE srnennmanu- ELIZABETH, new JERSEY, A oonronarron or nnw- Cooperating with the needle 1 are the i I lower looping devices which aremounted on the usual turret 6 and comprise theithreaded-looper 7, non-threaded looper v8, and loop'f detainers 9 and 10. The loopers 7 and 8are carried by the arms 11 and post 14 rising from-the turret 6; The loop} The turret carries the. usual needle-throat or button 16.

12 of arocking looper-carrier which is pivotedat 13 to the Referring to, ig. 1 it will be observed that the needle 1 having in the ine'antime been advanced from,

dotted line position, Fig; 2, tofull' line or loop-seizing position. The looper-thread 19" leads downwardly from the workjto the threaded looper 7 and, during the retraction of the looper Ttothe position shown injFig.

1, a pull is exerted on the looper-thread. 'Heretofo re thispull was exerted in-a direction from the last'stitch straightto' theeye of the threaded looper, and such direction p is rising from-its:depthstitch Y descent; ts loop 17 havmgbeen seized and was inclined at an angle of 45 or moreto the plane of'th'e work, making'fit diflicult to set up the concatenated loops without disturbing or dis-tendingthe loops previously set up.

In accordance with the present improve-- ment provislon is made for'supporting the looper-thread between the looper and the work, so that the looperethread length adjacent the last stitch will extend away from the buttonhole-slitin a more-nearly liorie zontal direction than heretofore, whereby the pull on the vlooper-threadwill have a large lateral component and an insignificant.

vertical component. By so supporting the looper-thread, the purl may be effectively pulled over to the buttonhole-slit and a uttonhole of satisfactory-appearance produced even though the looper oscillates about a horizontal axis as iscustomary in turretmachines.

The means for supporting the looperthread may conveniently be made up in the form of a horn 2O rigid with or secured to the loop-detainer 9 and having a downturned point 21 projecting forwardly beyond and over the horn 18, so as to pass below the looper-thread 19 and lift the latter toward the work 3. The horn also serves to separate the looper-thread from the needle-loop 17 and hold the looper-thread 19 clear of the horn 18 so that as the horn 18 advances to seize the needle-loop 17 it will not catch the looper-thread. On the slit-stitch descent of the needle, Fig. 4;, it passes in front of the looper-thread 19 and into the needle-loop 17 which is held spread by the horn 18 of the loop-detainer 9.

The invention is not to be understood as limited to the form and arrangement of parts shown and described as it is believed to be broadly new to provide means cooperating with the threaded-looper of an overseaming stitch-forming mechanism to bend the looper-thread between the looper and the last stitch andthereby facilitate the setting of the url close to the edge of the work;

aving thus set forth the nature of the invention, what I claim herein is 1. In overs'eaming stitch-forming mechanism, the combination with needle and looper devices for concatenating needle and looper threads to form a purl stitch, of means for bending toward the plane of the work the length of looper-thread between the looper and the last stitch, thereby facilitating'the setting of the purl close to the edge of the seam. a

2. In overseaming stitch-forming mechanism, the combination with needle mechanism and looper mechanism including threaded and non-threaded loopers operating alternately about substantially horizontal axes to seize needle-loops, of means for bending the length of looper-thread between the threaded loope'r and the last stitch toward the plane of the work while the non-thread- 4C. Overseaming stitch-forming mechanism comprising, needle mechanism operating to pass depth-stitch and slit-stitch needle-loops alternately through the work, threaded and non-threaded loopers operating alternately to seize such loops, and a loop-detainer having a horn for seizing the depth-stitch needle-loop on the non-threaded looper, said detainer having a second horn disposed above and projecting forwardly of said first mentioned horn and adapted to separate the looper-thread from the depth-stitch needle-loop. i

5. O'vei'seaming stitch-forming mechanism comprising, needle mechanism operating to pass depthand slit-stitch needleloops alternately through the work in different paths, a threaded looper for seizing the slit-stitch needle-loop, a non-threaded looper for seizing the depth-stitch needleloop and a pair of loop-detainers for seizing the loops from their respective loopers and positioning them unassisted bysaidloopers for entry by the needle, the loop-detainer which cooperates with the non-threaded looper being formed with a loop-seizing horn and with a looper-thread deflecting'horn overhanging the loop-seizing horn.

In testimonywhereof, I have signed my name to this specification.

EDWARD B. ALLEN.

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