US1787928A

US1787928A - Sewing machine

Info

Publication number: US1787928A
Application number: US307948A
Authority: US
Inventors: Axel F Carlson
Original assignee: Reece Button Hole Machine Co
Current assignee: Reece Button Hole Machine Co
Priority date: 1928-09-24
Filing date: 1928-09-24
Publication date: 1931-01-06
Anticipated expiration: 1948-01-06

Description

Jan 6, 1931. A. F. cARLsoN SEWING MACHINE Original Filed Sept. 24 1928 lnvenTon Axel F Carlson Patented den. 6, 1931 enrich Alf-1E1 F. CARLSON, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNOB TO THE EJIECE BUT-361T HGLE MAOHZNE QGMPANY, OF BQSTON, MASSACHUSETTS, A CORPORATION OF MAINE SEVJ'ING MACHINE Application filed. September 24;, 1928, Serial No. 307,948. Renewed May 28, 1980.

lhis invention relates to two-thread sewirg machines of that type which are adapted to sew a short seam and then come to and which are also provided with means for cutting the under thread close to the work at end of the'sewing operation. One of the objects of the present invention is to nrovide a novel means for holding the cutond of the under thread until the next sewing operation has begun, the thread-holdmo; means being constructed so as to hold the under thread in proper position to ensure the correct formation of the first stitch upon the beginning of the next sewing operation.

The invention is herein illustrated as it might he embodied in a machine of the type shown in my cc-pending application Serial No. 162 890, filed January 22nd, 192. The sewing machine illustrated in tion is designed for sewing huttonholes and the devices by which the under thread is manipulated are carried by a turret which rotatably mounted beneath the work and which has a rotative movement at each end of the huttonhole. The turret in turn is prov vided with a threat plate having a sewing opening in which the upper needle operates and through which the under thread-is led. in accordance with my presentinvention the throat plate is provided with a thread retaining notch so situated that when the turret'is rotated at the end of the sewing op eration the length of under thread which passes tl'irough the sewing; opening to the work will be drawn into the notch. and thereby held.

The thread-cutting mechanism cuts the under thri-wul between the throat plate and the work and by means of my invention the cut ei'id thus held in proper position to en sure thit it will be properly concatenated with the upper thread during the iirststitchtorming operati n the beginning of the next seam. V

In order to give an understanding of the invention I have illustrated in the drawings a selected. embodiment thereof which will now be described after which the novel features will be pointed out in the appended claims. Fig. l is a fragmentary plan View of a por said appiicav tion of the machine carrying the turret, said view lllustrating the turret and under thread cutting mechanism;

* Fig. 2 is a somewhat diagrammatic view illustrating the manner in which the under thread is drawn into; the thread-receiving notch; i I

Fig. 3 a. plan view of the throat plate with the Under thre retained therehyi Fig. 4 a

Inasmuch as the present invent-ion relates simply to the manner of retaining the under thread at the end of the sewing operation I have not thought it necessary to illustrate a complete sewing machine but have only shown asuflicient part of such a machine to enable the invention to he understood.

' The see 7 tion is a .ied is of the two-thread type it having an upper needle 1 by which the upper thread 2 is manipulated and it aiso having under-thread manipulating devices in the form of ioopers 3 and 4C and loop Spreaders 5 by which the under thread 6 is manipulated. I i

The under-thread handling mechanism is mounted on a tu ret 7 which is situated heeath the work support and which is 1'0- This turret 7 is rotatably mounted in hearings 11 carried by the frame portion 1 of the sewing machine as usualj In some buttonhole sewing machines the frame 12 which carries the turret and the stitcl1-for1ning mechanism is movable baclrand forth on the had portioni18 of the machine to wl 'ch the work 10 is clampedfthe to-and-fro motion of the frame 12 carrying the stitching down one side of the huttonliole and back along the other side of the buttonhole.

The machine herein illustrated is provided with thread-cutting mechanism for cutting the under thread beneath the work at the end of the sewingfoperation and the thread -cute view of the throatplatea machine to which this men is acted on by 7 thread will ting mechanism illustrated is similar to that shown in my co-pending application fie-rial No; 162,890. In this sewing machine when the sewing on the buttonhole has been compl-eted and the stitch-forming mechanism has been brought to rest the frame 12 is given a forward movement or a movement toward the bottom of Fig. 1thereby to shift the-parts V relatively from buttonhole sewing position to buttonholescutting position. During this movement the throat plate 8 will be carried forwardly of that end 14 of the buttonhole 15 at which the stitching was completed and a length of under thread 6 will be drawn out from the source of supply through the throat plate 8 as shown by the dotted lines (So in Fig. 2. I

in sewing machines of this type the stitchforming mechanism is frequently so arranged that when it comes to rest there will be a loop 16 of u or thread 2 retained b one of the P loopers of the under thread mechanism and hence when the parts are carried from buttonhole stitching to buttonhole-cuttmg position there Wlll be a length of under thread 664 and also a double length of upper thread 2a extending from the work to the throat plate shown by dotted lines Fig. 2.

The sewing machine illustrated in the above-mentioned application is provided with pull-down

arms

17, 18 which seize the length of threads 2a, 6a and pull them down away from the work from the dotted to the full line position Fig.2. Said machine is also provided with two

cutting elements

19 and 20 which are carried by pivoted arms 21,

and which at the proper timeare swung from their inoperative position shown in Fig. 1 into thread-cutting relatlon, thereby. cutting thethreads 2a, (3a between the throat 8 J and the work and close to the work. 7 r

The parts thus far described are, or may be, all shown and described inmy abovementioned co-pending application and hence not need to be further described herein. In accordance with my present invention the throat 8 is provided with a thread-retain ing notch n3 which has a general L shape, it

having the vertical portion 24 extending downwardly from thetop of the throat plate and then the lateral or horizontal portion 25.

tion of the notch.

the pull-down a'rms17, 18 said e drawn into the vertical por- The horizontal portion 25 of the notch has such a dimension that when the turret is turned at the end of the sewing operation to restore it to its initial position the under thread 6 will be drawn into said horizontal portion and because of the relatively narrow dimension of this horizontal portion 25 the thread 6 will be firmly gripped therein as shown in Fig. 3. Hence when the thread cutters, 19 and 20 operate to out the thread the severed end will be firmly gripped in the portion 25 of the thread-receiving notch. This notch so positioned that the portion of the thread extending from the notch to the under thread mechanism will be held in proper position to ensure its being concatenated with the upper thread during the first stitch-forming operation at the beginning of the next seam.

I claim:

1. A sewing machine, having in combination, stitch-forming mechanism comprising upperand under-thread handling devices, a

turret on which the under-thread handling devices are mounted, a throat plate carried by the turret and having a sewing opening through which the under thread passes to the work, and means to cut the under thread between the throat plate and the work, said throat plate having a thread-receiving notch which is brought into position to receive the under thread by the turning movement of the turret at the end of the seam.

2. A sewing machine, having in combination, stitch-forming mechanism comprising upperand under-thread handling devices, a turret on which the under-thread handling devices are mounted, a throat plate carried by the turret and having a sewing opening through which the under thread passes to the work, means to pull off a length of under thread, and means to out said thread close to the work, said throat plate havinga right angular thread-gripping notch into which the under thread is forced by the combined AXEL F. CARLSON.