US1373747A - Thread-cutting and thread-end-holding device for embroidery sewing-machines - Google Patents

Description

J. LINDSAY. THREAD CUTTING AND THREAD END HOLDING DEVICE FOR EMBROIDERY SEWING MACHINES.

APPLICATION FILED MAY I3, I9I=8-. 1,373,747. Patented Apr. 5, 1921.

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m mam Y J. LINDSAY. THREAD CUTTING AND THREAD END'HOLDING DEVICE FOR EMBROIDERY SEWING MACHINES. APPLICATION FILED MAY 13. l9l8.

73,747. Patented Apr. 5, 1921,

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JOHN LINDSAY, OF LUIRGAN, IRELAND, ASSIGNOR OF ONE-THIRD TO WILLIAM HENRY EVANS BROWN AND ONE-THIRD TO JAMES BELL, BOTH OF LURGAN, IRELAND.

THREAD-CUTTING AND THREAD-END-I-IOLDING DEVICE FOR EMBROIDERY SEWING- MACHINES.

Specification of Letters Patent. Patented Apr. 5, 1921.

Application filed May 13, 1918. Serial No. 234,279.

To all whom it may concern.

Be it known that. 1, JOHN LINDSAY, of Queen street, Lurgan, Ireland, a subject of the King of Great Britain and Irelanchhave invented certain new and useful Improve- ;ments Relating to Thread-Cutting and 1 proved means for cutting the threads above and below the material on which the sewing operation is being done, the cutting of the thread being efi'ected when the sewing operation has been completed at one part and it is desired to commence another sewing operation at a different place on the article being sewn.

The invention is particularly applicable to machine sewn embroidery, and like work, in which, at present, when one figure or portion of a pattern or design has been sewn, the upper and under threads are drawn along with the article on which the sewing is being done, to the point at which the next sewing operation is to be comumenced, and, so on, until the pattern or design has been completed, the portions of the thread between the various figures of the design having to be subsequently cut away. This invention obviates such subsequent cutting away or clipping, of the threads, thereby saving the cost of this operation and also saving the thread.

Under my invention the thread cutting means for embroidery and the like sewing machines is characterized by the cutting of the upper and under threads being effected by cutting mechanism which is brought into action on the completion of any particular sewing operation and is provided with safety locking means whereby the cutting mechanism can only be operated when the sewing needle is free of the cloth and also characterized by the mechanism for cutting the upper thread being caused to seize the thread above the cutting point and to hold same after the cutting operation and until several stitches have been made by the sewing mechanism whereby the cut thread is prevented from being drawn out of the eye of the needle by the take up mechanism, means being also provided to draw off the under thread ahead of the cutting operation 1n order to insure a sufficiency of thread below the cutting blade to take up the starting stitches of the next sewing operation.

In order that the invention may be clearly understood I have hereunto appended eX- planatory drawings, whereon, by way of illustration of example, the invention is shown applied to a l/Vheeler and lVilson 'sewing machine adapted for embroidery work. Figure 1 is a back elevation of the sewlng machine with my improvements applied thereto with the upper portion of the needle bar and appertaining parts broken off and shown separately in Fig. 1

Fig. 2 is a cross sectional elevation on the line 00, as, Fig. 1 and looking in the di rection of the arrow y.

Fig. 3 is an elevation looking on the driving end of the machine with the driving pulley removed to more clearly show the locking devices.

Fig. 4 is a detail plan V16W*Of the upper thread cuttingshears and showing them in the'out of action position.

Fig. 4: is a perspective view of the cutting shears in the out of action position as shown in Fig. 4.

Fig. 5 is a detail view corresponding to Fig. 4t but showing the cutting shears in the position which they occupy after cutting the upper thread.

Figs. 6 and 6 are detail views of the In carrying out the invention, as shown in the drawings, I provide a lever member 1 pivotally carried on the frame 2 of the machine, being connected therewith at the pivot point 3. The end 1 of the lever 1 is connected with a vertically slidable bar t connected with a foot treadle or equivalent (not shown) whereby the end 1 of the lever 1 can be pulled down against the action of a spring 5. A downward movement of the lever end 1 causes its end 1 (shown broken off) to be correspondingly raised. The end 1 of the lever 1 is connected with the presser foot lifting mechanism, being engaged ina slot in a vertically slidable bar 6 which connects with the presser bar 7 in such manner that the raising of the bar 6 by the end 1 of the lever 1 will effect a raising of the presser foot bar and so raise the presser feet of the machine. The raising of the end 1 of the lever 1 also presses back the cam-shaped end 8 (see also Fig. 2) of a lever 8 pivotally connected, at 8 with the machine head 9. This lever 8 is made, at its other end 8, with a slot 8 which, when the end 8 is pressed backward, as above described, is caused to come into the path of movement of a spring catch 10 provided at the top of the needle bar. 11. The needle bar 11 has a sleeve 11 surrounding it and connected directly with the needle operating mechanism, and the needle bar 11 can be connected with and disconnected from this sleeve 11 by means of the spring clutch or catch 10 which has a hook 10 adapted to engage a projection 11 at the top of the needle bar sleeve 11. While the machine is sewing, the hook 10 of the spring catch 10 remains in engagement with the projection 11 on the needle bar sleeve and so efiects the reciprocation of the needle bar 11 and needle 12. When, however, the lever 1 is operated for the purpose of actuating the cutting mechanism as hereinafter described, it is necessary that the needle should be held up clear of the cloth. For this purpose the catch 10 comes into operation to disconnect the needle bar 11 from its operating sleeve 11 by the raising of the end 1 of the lever 1, causing a forward movement of the end 8 of the lever 8 whereby the slot 8 therein is caused to engage the backwardly projecting portion 10 of the catch 10 sothat the catch 10, and the needle bar 11 connected therewith, are prevented from descending while the sleeve 11 continues in action during the thread cutting operation. Connected with the lever 8, at 8, is an end 13 of another lever 13 which is pivotally connected with the machine :head at 13 and has its other end 13 connected with the upper end 14 of a member 1 1- which, at its lower end 1 1 carries the upper thread cutting shears. The

member 14; is turnably supported on. a bracket 15 projecting from the bar 7 which carries the presser feet 7 and 7 and, atfthe lower end 149, the member 14 has a plate 14 pivotally connected to it and to which the cutting shears 15 and 15 (Figs. 1 1 and 5) are pivotally connected. The cutting shears 15 and 15 extend forward on each side of'the presser foot bar 7 and needle 12. When the shears 15 and 15 are moved back, by the raising of the front 7 end 1 of the lever 1, to the position immediately above the needle hole in the throat plate, the cutting members 15 and 15 of the shears are also moved toward one another from the position shown at Figs. 1 and 4 to the position shown at Fig. 5 this movement being obtained from a bar 16 which passes through thepresser bar 7 and has, at its lower end, arms 16 and 16 carrying pins 16 and 16 which engage in slots 15 and 15 in the shear members 15 and. 15 The upper end of the bar 16 is cranke-.. as shown at Fig. 2 and the cranked end 16 is connected by a link 17 with a member 18 pivotally connected with the lever 1 at 18 and projecting above the lever 1 andhaving a slot or opening. 18 therein. bar 16 is turned to efiect the cutting of the thread, the portion 15 of the cutting mem-' ber 15 pushes the thread under the cutting edge 00 and draws off a certain amount into the jaws of the cutting member 15 (Fig. 4) and after the cutting operation has taken place by the meeting of the cutting edges 22, m the upper thread is held between the members 15, 15 above the cutting point so long as the shearing members 15 and 15 remain in the position shown at Fig. 5. Immediately after the cuttingoperation the shears 15 and 15 close with the upper thread held between the meeting edges of the cutting members 15 and 15 to prevent the take up drawing the thread out of the eye of the needle, until a number of stitches have been made by the sewing mechanism. This holding of the upper thread is effected by a catch 19 which is pivotally connected at 19 with the plate 20 and has, atits end 19 a projecting pin 19. This pin 19 is capable of being engaged in the opening 18. of the member- 18 on the lever 1 and, when it is in engagement therewith, the shears 15 and 15 are closed, with themembers 15 and 15 holding the upper thread. The opening 18 in the member 18 allows the latter to move in the direction of the arrow 2 (Fig. 1) under the action of a spring 21. This movement of the member 18 effects a corresponding movement of the link 17 and cranked bar 16 whereby the pins 16 and 16 are turned in such manner as to close the shearing members 15%. and 15 and so cause the portion 15* to coiiperate with the cutting member 15 to hold the upper thread so long as the pin 19 remains in the opening 18. In order to hold the upper thread, after the cutting operation, and to release it when the predetermined number of stitches have been sewn, a slidably supported ratchet member 22 is provided having slots 22 and 22 engaging pins 19 and 19 on the catch 19. When the machine is running and the cutting device is not in act on the pm 19 of the catch 19 will bein the position shown at Fig. 1 and the ratchet member 22 will be out of engagement with the pawls and 24; when, however, the cutting mechanism has been operated and the end 1 of the lever 1 has been lowered so that the pin 19engages in the opening 18 in the member 18, the raising of the lever end 1 will bring the When the teeth of the ratchet member 22 into engagement with the pawls 23 and 24:. This upward movement of the member 19 is effected against the action of a spring 26. The pawl 23 is connected with the stud 25 of the cross over cam and the usual oscillation of the stud 25 causes the pawl 23 to move the ratchet member 22 toward the member 18 by a step-by-step movement, corresponding to the number of stitches required to be made before the release of the upper thread from the shearing members and, in completing this movement, the ratchet member 22 will tilt over the member 18 until the pin 19 is clear of the opening 18 whereupon the spring 26 will pull down the member 19 to the position shown at Fig. 1 and the re-action of the spring on the member 18 will cause same to open the shear members 15 and 15 so as to release the thread. During the forward movement of the ratchet member 22 the pawl 24 holds the ratchet member and prevents it moving back when the pawl 23 is lifted at each oscillation of the stud 25. The ratchet member 22 moves forward against the action of a spring 27 which re-acts to pull back the ratchet member 22 when the pin 19 has dropped clear of the opening 18 as above described.

In order to prevent the possibility of the cutting mechanism being operated, when the needle is in the cloth, I provide an automatic locking device as shown at Figs. 1 and 3. This locking device consists of a cam member 28 secured on the machine shaft 29 and adapted to act on a locking member 30 having a portion 30 which normally projects under a portion 1 at the end 1 of the lever 1 so as to lock same except at such times as the cam 28 moves the locking member 30 clear of the part 1 of the lever 1. The cam 28 is arranged to move the lever member 30 clear of the part 1 when the take up is at its highest point with the needle clear of the cloth. I also provide a locking lever 31 which has a portion 31- normally under the projecting part 1 of the lever 1 so as to prevent the operating of the lever 1 and cutting mechanism but which, by a pull on its end 31*, can be moved by the operator so as to be clear of the part 1 of the lever 1 in order to allow of the cutting mechanism being operated when required. The end 31 of the locking lever 31 would be connected to a suitable operating treadle or equivalent. A spring 32 keeps the locking member 30 in contact with the cam 28 and a spring 31 keeps the locking lever 31 normally in the locked position.

The under thread is cut simultaneously with the upper thread, or slightly later, by means of a cutting blade 33 which cooperates with a cutting edge or cutting portion 3 1 on the underside of the throat plate 34. This cutting blade 33 is actuated by the ting operation is adapted to push the thread ahead of the cutting edge 33 and to draw off suflicient thread below the shearing point to provide a sufficiency of under thread for the starting stitches at the next sewing operation.

Although I have described the cutting mechanism as operated by the foot it may be operated by hand or by the knee.

Having now fully described my invention what I claim and desire to secure by Letters Patent is 1. In or for sewing machines for doing embroidery or like work on cloth, cutting mechanism for cutting the upper and lower sewing threads, means connected with the pressure bar of the machine, for operating said upper thread cutting mechanism, means for operating said under thread cutting mechanism, and a pivotal catch and sliding member whereby the upper thread, after being cut, is held and prevented from being drawn out of the eye of the machine needle until several stitches have been made by the machine.

2. Thread sewing devices for embroidery sewing machines comprising a lever pivoted to the head of the machine, a lever connected with the first mentioned lever and connected with another lever supported by the pressure bar of the machine, a plate on the last mentioned lever, a pair of horizontally disposed levers pivotally supported on the plate, thread cutting and holding devices for the upper thread carried by the horizontally disposed levers and means whereby 'the operation of the levers to efiect the cutting of the thread is prevented except when the needle of the machine is clear of the cloth.

3. In or for sewing machines for doing embroidery or like work on cloth, cutting mechanism for cutting the upper and lower sewing threads comprising upper cutting blades, means for operating same, an under cutting blade, means for operating same, means preventing the blades operating when the needle is in the cloth and an extension .on the under cutting blade for drawing oil? a sufficiency of thread for the starting stitches of the next sewing operation.

In testimony whereof I aflix my signature in presence of two witnesses.

JOHN LINDSAY. Witnesses:

ANDREW HAMILTON, J orm Knox.

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