US1193906A

US1193906A - Apparatus for cutting thread in sewing-machines

Info

Publication number: US1193906A
Authority: US
Publication date: 1916-08-08
Anticipated expiration: 1933-08-08

Description

i A. E. LINDNER.

APPARATUS FOR CUTTING THREAD IN SEWING MACHINES.

APPL]CATION FILED JAN-2.1915.

l 1 93,996 Patented Aug. 8, 1916.

2 SHEETSSHEET I- A. E. LINDNER.

APPARATUS FOR CUTTING THREAD IN SEWING MACHINES.

APPLICATION FILED JAN.2. 1915.

l ,1 93,906. Patented Aug. 8, 1916.

2 SHEETS-SHEET 2.

III/0 3 vweutoz ARTHUR E. LINDNER, OF BROOKLYN, NEW YORK.

APPARATUS FOR CUTTING THREAD IN SEWING-MACHINES.

Application filed January 2, 1915.

To all whom it may concern Be it known that I, ARTHUR E. LINDNER, a citizen of Germany, and a resident of Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Apparatus for Cutting Thread in Sewing-Machines, of which the following is a specification.

This invention relates to apparatus for cutting thread in sewing machines, and particularly those known as button sewingand button hole machines.

An object of the invention is to provide a cutting means by which two only of the three limbs formed by the two threads below the cloth and button or below the button hole, are cut, the third limb connected to the needle being left whole.

A further object is to provide a cutting device by which after a button-is sewed on a sure close cutting of the threads is accomplished, and the correct lengths of thread are left from the needle and bobbin for the neXt sewing operation.

With these and other objects in view my invention consists of the novel features, construction and combination of parts, hereinafter more fully described and pointed out in the claims.

In the drawings, Figure 1 is a side elevational view of a button sewing machine embodying my invention, Fig. 2 is a top plan view of the bed plate thereof with button holding attachment removed, Fig. 8 is a sectional detail view showing the position of the threads at the beginning of the sewing of a button, Fig. 1 is a similar view showing the position of the threads when the sewing of a button is completed, Fig. 5 is an end view of the arrangement shown in Fig. 4, and Figs. 6, 7 and 8 are details of the cutting device.

Similar reference characters indicate corresponding parts throughout the several views.

Referring to the drawings and more particularly to Fig. 1 thereof, a button sewing machine 1 of well-known construction is provided with a needle 2, having reciprocating rectilinear movement, adapted to alternately pass through each hole of a button, and a button'holder 8 adapted to be raised and lowered from the cloth in a manner well-known. Longitudinally of the bedplate 4 of the machine is provided a slot 5 in which is sildably mounted a bar 6 at the Specification of Letters Patent.

Patented Aug. 8, 1916.

Serial N0. 238.

end of which is secured the cutting member 7 The said bar is reciprocated by means of a bell crank lever 8 pivoted to the bed plate at 9, and connected to the said bar by a lever 10 pivoted at 11 and a link 12. A screw 13 and wing nut 14 are fitted into the handle 15 of the lever 8 for adjusting the position of the bar 6. A spring 16 is secured between the said bell crank lever and the bed plate of the machine to hold the same in non-operating position, and 'a stop 17 is secured to the bed plate to limit the movement of the said bell crank lever. The end of the cutting member-7 projects into the opening 18 of the bed plate so that it rests under the cover plate 19 thereof just behind the longitudinal opening 20 therein for the passage of the needle 2. A longitudinal slot 21 is provided centrally of the cutting member in alinement with the opening 20, which embraces during operation the limb of thread from the needle, not to be out. At either side of the said slot are provided inwardly inclined knife edges 23 and 24 which recede to the base of the curved side walls of the forwardly projecting portions 25 and 26. Forwardly of the opening 20 is provided the thread guiding member 27 adapted to be moved rearwardly by operation of the bar 28. The said guiding member is provided with a short slot 29 in alinement with the slot 21 of the cutting member and the opening 20, and to either side of the said slot there are provided thread guiding surfaces for guiding the limbs of thread in the path of the cutting edges 23 and 24. The guiding surface 30 for the bobbin limbs of thread, which is cut by the cutting edge 24-, is arcuate in shape, the limb being guided. outwardly to the lower point of the are which is in the path of the said cutting edge 24. The guiding surface 31 for the needle limb of thread is inclined to a notch 32 in the path of the cutting edge 23, the limb being guided into the said notch where it is securely held to be cut. The center limb of thread from the needle is untouched during the cutting operation, the same being embraced by the walls of slots 21 of the cutting member, and 29 of the guiding member.

In Figs. 3, A and 5 of the drawings I have shown a button 33 being sewed to a piece of cloth, and I have shown diagrammatically the circular bobbin 85, oscillating shuttle 36 and oscillating driver 37 of the well-known type. The two limbs of thread forming the loop from the needle are indicated in the drawings as A and B, the former being the center or uncut limb and the latter the limb to be out, and the bobbin limb of thread is indicated as C.

The operation of my improved cutting device is as follows :-The button 33 is sewed on to the cloth in the well known manner, the position of the limbs of thread at the beginning of the operation being indicated in Fig. 3 and at the end of the operation in Figs. 2, 4, 5 and 6, the limb A being in the center and the limbs of thread B and C at either side thereof. When the proper number of stitches have been made to sequre the button to the cloth, the needle 2 is auto-' matically stopped, the guiding member 27 is brought from the position shown in Fig. 6 to that shown in Figs. 7 and 8, and the button holder is lifted to release the cloth, by operation of the cam wheel 38 shown in Fig. 1, which revolves once for each button sewed. At the end of its revolution a projection 39 thereon pushes upward the end of a rod 40 loosely mounted on the shaft 41, thereby causing the forward end of the rod to be lowered and releasing the lever 42 normally held in position in the recess 43 of the rod 40 by a pin 44 thereon. The movement of the rod 40 causes the forward movement of the belt shifting member 61 which shifts the belt 62 from the pulley 63 to the pulley 64, causing the automatic stopping of the needle. The lever 42 is connected by a link 42 to an arm 42 which is keyed to the shaft 41. The lower end of the said lever is connected to a shiftable shaft 46 provided at the ends with

beveled gears

47 and 48. When the lever 42 is released, the said shaft 46 is shifted by means of a spring 49, so that the beveled gear 47 meshes with a beveled gear 50, which is constantly driven by the driving mechanism, and the bevel gear 48 meshes with a beveled gear 51 carried by a cam disk 52, which is then caused to rotate. An eccentric cam groove 53 is provided in the disk 52, which is engaged by an anti-friction roller 54 carried on the end of the bar 28, so that when the disk 52 is rotated the bar 28 and the guide member 27 are moved forwardly. Simultaneously with this action, an arm 55 also keyed to the shaft 41, is moved forwardly. This arm 55 is connected by means of a rod 56 to one arm of an elbow lever 57 pivoted at 58 to the frame, 1. The other arm is provided with a forked end 59 which engages an upwardly extending portion 60 of the button holder, and causes the same to be raised.

As the guiding member 27 is being brought forward it engages the limbsof thread A, B and G, embracing the center limb A and guiding outwardly the limbs B and G into the path of the cutting edges 23 and 24. The handle 15 of the lever 8 is operated to thrust the cutting member 7 forwardly, thereby cutting the limbs B and C and leaving the thread A whole, by reason of the slot 21. WVhen so cut, the spring 16- serves to draw the cutting member back into position, and a handle 45 shown 111. Fig. 1

which is connected to the shaft 41 is de-- pressed to reset the machine for sewing on the next button.

I have shown a preferred and satisfactory embodiment of my invention, but it is obvious that changes may be made therein without departing from the spirit and scope thereof as defined in the appended claims.

I claim:

1. A thread cutting device for sewing machines, comprising a cutting member consisting of a single plate, provided with an elongated slot therein, adapted to embrace one limb of thread notto be cut, cutting edges at either side of said slot adapted to cut limbs of thread not embraced by said slot and means for moving said cutting member into engagement with the said thread. p

2. A thread cutting device for sewing machines, comprising a cutting member provided with a longitudinal slot adapted to embrace one limb of thread not to be cut, inclined cutting edges at either side ofsaid slot adapted to cut limbs of thread not em-.

braced by said slot and means for reciprocating sald cutting member.

3. A thread cutting device for sewing chines, comprising a cutting member, provided with a longitudinal slot, adapted to embrace one limb of thread not to be cut, in clined cutting edges at either side of said slot adapted to cut limbs of thread not. 8111-.

braced by said slot, means for reciprocating said cutting member, and guiding means adapted to move said limbs in the path of said slot and cutting edges.

4. A thread cutting device for sewing machines, comprising a cutting member having as my invention, I have signed my name in presence of two subscribing witnesses. I

ARTHUR E. LINDNER. Witnesses:

F. Hose, D. LnwIs MATTERN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner .of Patents;

Washington, D. C.