US1197797A - Thread cutting and clamping device for sewing-machines. - Google Patents

Description

G. COLE.

THREAD CUTTING AND CLAMPING DEVICE FOR SEWING MACHINES.

APPUCATION man MAR-17.19M-

1,197,797, Patented S t. 12,1916.

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G. COLE.

THREAD CUTTING AND CLAMPING DEVICE FOR SEWING MACHINES- APPLICATION FILED MAR 17, 1915.

Patented Sept. 12, 1916;

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UNITED sTAs PATENT orrrc.

GLENN COLE, or CHICAGO, ILLINoIs, ASSIGNOR To THE 'RE'ECE BUTToN HOLE MACHINE COMPANY, or BOSTON, MASSACHUSETTS, A CORPORATION or MAINE.

THREAD CUTTING AND CLAMPING DEVICE FOR SEWING-IIIACHIN Specification of Letters Patent. Patented Sept 12, 1916.

Application filed March-17,1915. Serial No.;15,025.

T 0 all whom it may concern Y Be it known that I, GLENN COLE, a citizen of the United States, residing at Chicago, county of Cook, State of Illinois, have invented an Improvement in Thread Cutting and Clamping Devices for Sewing-Machines, of which the following description, in connection with the accompanying drawing is a specification, like characters on the drawing representing like parts.

This invention relates to sewing machines and has for its object to provide a noveldevice for cutting the needle thread at the end of the stitching operation and for clamping the end of the thread leading to the source of supply until the stitching operation is started again thereby relieving the operator of this duty and insuring the correct formation of the first stitches when the machine is started.

While my invention is capable of use in connection with sewing machines of clifferent types, I have chosen herein to illustrate it as it would be employed in a buttonhole sewing machine of the well-known Reece type, examples of which are shown in the following United States patents: No. 49%,280, March 28, 1893; No. 655,687, August 7, 1900; No. 1,030,589, June th,-1912. Buttonhole sewing machines of this type are provided with worl'z-clamping means and stitch-forming mechanism which have a movement relative to each other not only to give the work a relative feeding movement during the stitching on the buttonhole, but also to move the parts from buttonholecutting position to stitching position before the stitching operation on the bnttonhole be gins and then to return the parts to buttonhole-cutting position from stitching position after the buttonhole has been completed. Said machines are also provided with a buttonhole-cutting device which operates to cut the buttonhole either before or after the stitching'operation and when the parts are in buttonhole-cutting position. The construction of machines such as illustrated in the above-mentionedpatents is such that the machine is brought to rest at the end of a predetermined. cycle of operations with the parts in buttonhole-cuttlng position, and when the machine is started the work-clamping means and stitch-forming mechanism are given a relative movement to bring them from buttonhole-cutting tonhole has been completed, the stitch-forming mechanism is brought to rest and the .work-clamplng means and, stitch-forming mechanism have a further final relative movement tobrin'g them into their initial position, during which final movement the work is automatically unclamped. The buttonhole-cutting mechanism operates to cut the buttonhole when the parts are in their buttonhole-cutting position and either before or after the stitching operation.

My present invention comprehends a novel thread-clamping device which is rendered operative automatically by the relative movement of the stitch frameand workclamping means to clamp theneedle thread above the work after the stitching operation has been completed on a buttonhole and during the final relative movement of the stitch-forming mechanism and work-clamp ingmeans by which theyare brought from stitching position into buttonhole-cutting position and to hold the end of the needle thread firmly clamped until the machine has been started for stitching the-next succeeding buttonhole and the initial stitches are being formed, after which the thread is antomatically released. Associated with the thread clamp is a thread cutter by which the needle thread is out after it has been clamped.

In my improved device the clamping of the needle thread is accomplished while the stitch-forming mechanism and work-holding means have one positionvrelative to each other, that is, while they are moving from their stitching to buttonhole-cutting position, and the unclamping of the needle thread is accomplished while they have an- .other position relative to each other, that is, while they are in stitching position. 'means which I have herein illustrated for actuating the thread-clamping device by The the relative movement between the stitch frame and clamp frame is such as to cause the needle thread to be clamped when the stitch frame and clamp frame have one position relative to each other and to cause the needle thread to be unclamped when they have another position relative to each other.

In order to give an understanding of my 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.

Figure 1 of the drawings is a side view of a portion of a buttonhole-stitching machine of the Reece type having my improvements applied thereto; Fig. 2 is a plan view of Fig. 1 with a portion of the overhanging arm of the stitch frame broken out; Fig. 3 is an enlarged side view of my improved thread cutter and clamp showing the parts in different positions; Fig. is a section on the line x50, Fig. 2; Figs. 5, 6, 7, 8 and 9 are fragmentary detail views of the clampactuating member showing the parts in different positions.

In the sewing machine herein illustrated, the stitch-forming mechanism is supported on a so-called stitch frame 1, and it comprises the usual upper and under threadhandling mechanism which cooperate to concatenate the edge stitches of the buttonhole. The under thread-handling mechanism is not herein illustrated, but is of the usual construction found in buttonhole sewing machines of the Reece type. The upper thread-handling mechanism is shown as comprising an eye-pointed needle 4 carried by the usual needle bar 3 which reciprocates in bearings in an overhanging arm 2 formed on the stitch frame 1. The workclamping means is herein shown as the usual work clamps 5 carried by arms 6 that are pivoted at 80 to a frame 7 hereinafter referred to as the clamp frame, all as usual in buttonhole sewing machines of the abovementioned type. The parts are shown in full lines in Fig. 1 in buttonhole-cutting position, that is, in the position they occupy when the machine has been brought to rest at the end of the stitching operation on a buttonhole, and as is well known to those familiar with buttonhole sewing machines of this type, when the machine is started the work clamps 5 are first operated to clamp the work in position and the cutter 90 is operated to cut the buttonhole. The stitch frame 1 and clamp frame 7 then have a relative movement to bring the needle into the dotted line position, Fig. 1, at which time the stitching mechanism is set in operation to begin the stitching of the buttonhole. During the stitching of the buttonhole, the stitch frame and clamp frame have a relative movement to insure the proper feeding of the work, and the stitch-forming mechanism also has a turning movement to enable the stitches to be formed around the ends of the buttonhole, and after the buttonhole has been completed, the stitch frame 1 and clamp frame 7 have a further relative movement to bring the parts into the relative position shown in Fig. 1, during which movement the work is unclamped automatically and the clamps 5 are raised. When the stitching on any buttonhole has been completed, the stitch frame has such position that the needle and needle bar occupy approximately the dotted line position, Fig. 1, and the final relative movement between the stitch frame and clamp frame by which they are carried from stitching position to buttonhole-cutting position, results in carrying the needle and needle bar from the dotted to the full line position, Fig. 1.

Inasmuch as the operation of a buttonhole sewing machine of the above type is well known to those skilled in the art, it is not necessary to further describe its construction or operation.

As stated above, I have provided herein a novel thread clamp which is rendered operative automatically by the relative movement between the stitch frame and clamp frame to grip or clamp the needle thread after the stitching operation is completed on any buttonhole and while the stitch frame and clamp frame are having their final relative movement from stitching position to buttonhole-cutting position, which thread clamp holds the end of the needle thread leading to the needle until the stitch-forming mechanism and work-holding means are again carried into stitching position relative to each other and the stitching has commenced on the next succeeding buttonhole thereby insuring that when the stitching operation is begun the first stitch will be properly formed without danger that the end of the needle thread will be drawn through the work when the needle loop is being formed during the first stitch.

My improved thread-clamping device is rendered operative to clamp the thread when the stitch-forming mechanism and work clamps are in one position relative to each other and to release the thread when they are in another position relative to each other.

My improved thread-clamping device is herein shown as carried by the work-clamp ing mechanism and it is illustrated as comprising two relatively. movable clamping jaws 8 and 9 carried by two arms 10 and 11, respectively. The arm 10 is fixedly mounted to one of the arms 6 of the work-clamping mechanism. in some suitable way, as by means of a screw 13, and the arm 11 is shown as pivotally mounted to the arm 10, as at 12, said arm 11 having a slot 14. therein in which operates a pin 15 carried by the arm 10, said slot operating to limit the swinging movement of the arm 11. The clamping jaw 8 is thus a stationary jaw, and theclamping jaw 9 is a movable jaw. Means are provided for closing the jaws together when the stitch frame and clamp frame are moving from stitching to buttonhole-cutting position, and these clamping jaws are so positioned that during such relative movement the needle thread t will be drawn between them. The closing of the jaws thus clamps the needle thread. Said means are also constructed so that they will hold the jaws closed until after the stitch-forming mechanism and work-holding means move from buttonhole-cutting into stitching position when the machine is again started, said means operating to permit the jaws to open to release the thread just as the initial stitches are formed on the next succeeding buttonhole. These means, therefore, close the thread-clamping jaws to clamp the thread when the stitch-forming mechanism and work-clamping means are in one position relative to each other and permit the jaws to open to release the thread when they are in another position relative to each other. In the illustrated embodiment of my invention the jaws are normally held open by a spring 25 which is secured to an arm 23 extending from the arm 11. For closing the jaws at the proper time and for holding them closed until the needle thread is to be released,'I have herein provided a clamp-actuating member 16 which is secured to the stitch frame and cooperates with the arm 11 as the stitch frame and clamp frame have their relative movement to move the jaw 9 against the jaw 8. This clamp-actuating member 16 is shown as adjustably secured to a bracket 17 by means of two screws 19 which extend through a slot 20 formed in the end of the member 16, and the bracket is secured to the stitch frame by a screw 18, this construction providing for any necessary adjustment of said clamp actuating member. The clamp actuating member 16 is preferably somewhat resilient, and it is formed at its end with a cam portion 21 and with a projection or extension 22 below the cam portion. This cam portion 21 and extension 22 coiiperate with the downwardly-extending portion 24 of the finger 23 which extends laterally from the arm 11 carrying the movable clamping jaw 9, thereby to clamp the needle thread 6 and to release the latter at the proper times in the cycle of operations.

As stated above, the parts are shown in Figs. 1 and 5 in the positions they assume when the machin has been brought to rest at the end of the stitching operation on a buttonhole, and it will be noted that the portion 24 of the finger is engaged by the cam portion 21 of the clamp-actuating member 16 and is above the extension 22. lVhen the machine is started the work clamps 5 are first depressed to clamp the work in position and the stitch frame and clamp frame are moved relative to each other to bring the needl 4 into the dotted line position, Fig. 1, at which time the stitching operation begins. When the stitching on the buttonhole has been completed the needle occupies substantially the dotted line position, Fig. 1, and the work clamps 5 are still depressed. During the stitching operation the threadolamping jaws 8 and 9 are separated from each other, as shown in dotted lines Fig. 2, this being accomplished by means of the spring 25, as above described.

The work clamps 5 are released automatically at the termination of the stitching operation and while the needle is in approximately the dotted line position Fig. 1, and this releasing movement of the clamps brings the portion 24 of the finger 23 into line with the cam 21 of the clamp-actuating member. WVhen the stitch frame and clamp frame have their final relative movement to carry the needle from the dotted to the full line position, Fig. 1, the needle thread is carried between the two jaws 8 and 9, which it will be understood are separated from each other by the action of the spring 25. This relative movement of the stitch frame and clamp frame also causes the clamp-actuating member 16 to move relative to the finger 23, thus bringing the cam 21 into engagement with the portion 24 of the finger, as shown in Figs. 1 and 5. The action of the cam 21 on the finger 24 is to force yieldingly the arm 11 laterally, thereby closing the clamping jaw 9 against the clamping jaw 8. This operation, as stated above, occurs after the stitch frame and clamp frame have had sufficient relative movement to bring the needle thread t between the clamping jaws so that the action of the cam 21 on the portion 24 resultsinclamping the portion of the needle thread between the needle and the work between the two clamping jaws S and 9. When the machine comes to rest in the full line position, Fig. 1, the needle thread is thus clamped between the jaws 8 and 9 and is held clamped by the action of the member 16 on the extension 24 of the finger 23.

When the machine is set in operation for' sewing the neXt succeeding buttonhole the work clamps 5 are first depressed, thus carrying the portion 24 of the finger 23 down wardly into the position shown in Fig. 6. This movement does not, however, release the thread clamps 8 and 9 because the portion 22 of the member 16 is still in engagement with the downwardly-turned end 24 of the finger 23. After the thread is clamped the stitch frame and clamp frame have a relative movement before the stitching operation begins to bring the needle into the relative position shown in dotted lines Fig.

1, and during this movement the downwardly-extending portion 2 1 of the finger 23 is in engagement with the inner face of the extension 22 of the member 16, as shown in full lines Figs. 2 and 3. At the time that the stitching operation begins the parts are in approximately the position shown in Figs. 2 and 3 and the end of the needle thread is still clamped between the jaws 8 and 9 so that when the first stitch on the buttonhole is formed the end of the needle thread will be firmly held in the thread clamp to insure the correct formation of the first stitch. As the stitching operation proceeds the stitch frame and clamp frame have a relative feeding movement to stitch down one side of the buttonhole, and during this movement the extension 22 is withdrawn from the portion 2 1 of the finger 23, as shown in Fig. 7. The disengagement of these parts, however, does not actually take place until after the first stitch has been formed. As soon as the extension 22 has been withdrawn from the portion 24 of the finger 23, the spring 25 acts automatically to open the thread-clamping jaws thereby to release the end of the needle thread, but as stated above, this does not occur until after the first stitch at least has been formed. During the further operation of stitching the buttonhole, the stitch frame and clamp frame have a relative movement to still further withdraw the member 16 from the finger 23 as the stitching is carried down one side of the buttonhole. When the stitching is carried around the end of the buttonhole and up the other side, the member 16 will be moving toward the finger 23, but as the thread-clamping jaws are opened the portion 2% of the finger 23 occupies the dotted line position in Fig. 2. As a result, the projection 22 of the member 16 will pass in behind the portion 24L of the finger 23.

Wl1en the stitching operation is completed the relative movement between the stitch frame and clamp frame has brought the parts into substantially the position shown in Fig. 8. At this time the work is unclamped automatically and the raising of the clamps and their arm 6 carries the por tion 24: of the finger 23 upwardly in front of the cam 21 as shown in Fig. 9. At this time the clamping jaws S and 9 are opened and in position to receive the needle thread If between them when the stitch frame and clamp frame have their final relative movement to carry them into the relative posi tion shown in full lines Fig. 1. During this relative movement the cam 21 engages the portion 24: of the finger 23 and forces the arm 11 laterally thereby shutting the clamping jaw 9 against the jaw 8 and clamping the needle thread as above described.

It will thus be seen that I have provided a thread-clamping device which is rendered operative by the relative movement of the workclamping means and stitch-forming mechanism to clamp automatically the needle thread at the end of the stitching operation and to release said needle thread when the stitching has begun on the next succeeding buttonhole. It will also be seen that the device herein illustrated is so constructed that the clamping of the needle thread is accomplished when the stitchforming mechanism and work-clamping means are in one position relative to each other while the release of the needle thread is accomplished while they are in another position relative to each other. With my device the operator is relieved entirely of the duty of holding the end of thevneedle thread when the stitching operation is commenced.

Associated with my thread-clamping device is a thread cutter by which the needle thread is automatically severed. This thread cutter is shown as a blade 26 fastened to the underside of the clamping jaw S. The thread is cut by the operation of shifting the work into position to have a fresh buttonhole stitched. When a buttonhole is completed and the needle thread has been clamped, as above described, the needle thread extends from the clamp directly to the work. After the work has been unclamped the operator shifts it laterally into correct position to have the next buttonhole stitched, and this lateral shifting movement of the work brings the needle thread 25 against the edge of the cutter 26, as shown by the dotted lines Fig. 4, thus automatically severing the needle thread.

While I have illustrated herein a selected embodiment of my invention, I do not wish to be limited to the constructional features shown. Further, I wish to state that while the invention is shown as applied to a buttonhole sewing machine of the Reece type, yet it is equally applicable to other types of sewing machines.

I claim:

1. In a sewing machine, the combination with stitch-forming mechanism, of workclamping means situated above the work, said stitch-forming mechanism and workclamping means having a movement relative to each other in a direction parallel to the work held by said work-clamping means to effect a predetermined cycle of operations including a stitching operation, a thread-clamping device carried by the work-clamping means, and means rendered operative by said relative movement to cause the thread-clamping device to clamp the thread at the end of the stitching operation.

2. In a sewing machine, the combination with stitch-forming mechanism, of workclamping means situated above the work,

said stitch-forming mechanism and workclamping means having a movement relative to each other in a direction parallel to the work held by said work-clamping means to effect a predetermined cycle of operations including a stitching operation, a thread-clamping device carried by the work-clamping means, and means rendered operative by said relative movement to cause the thread-clamping device to clamp the thread at the end of the stitching operation and to release the thread immediately after the formation of the initial stitches of the next succeeding stitching operation.

3. In a buttonhole sewing machine, the combination with stitchforming mechanism, of workclamping means situated above the work, said stitch-forming mechanism and work-clamping means having a movement relative to each other during which the stitching around a buttonhole is performed, thread-clamping jaws carried by the work-clamping means, and a clampactuating member secured to the stitch frame and adapted to actuate said jaws to clamp the thread therebetween during such relative movement at the end of a stitching operation on a buttonhole.

l. In a sewing machine, the combination with stitch-forming mechanism, of workclamping means situated above the work, said stitch-forming mechanism and workclamping means having during each cycle of operations a movement relative to each other both during and after a predetermined stitching operation, a thread-clamping device carried by the work-clamping means, and means rendered operative by said relative movement to cause the thread-clamping device to clamp the thread at the end of the stitching operation when the stitch-forming mechanism and work-clamping means are in one position relative to each other and to release the thread as the initial stitches of the next succeeding stitching operation are being formed and when the stitch-forming mechanism and work-clamping means are in another position relative to each other.

5. In a sewing machine, the combination with a stitch frame carrying stitch-forming mechanism, of a clamp frame, said frames having a movement relative to'each other, a work-clamping member carried by the clamp frame and movable relative thereto into and out of operative position to clamp and unclamp the work, thread-clamping means carried by said work-clamping member, and means rendered operative by the relative movement of the frames to clamp the thread in said thread-clamping member at the end of the stitching operation.

6. In a sewing machine, the combination with a stitch frame carrying stitch-forming mechanism by which predetermined stitching operations are performed, of a clamp frame, said frames having a movement relative to each other both during and after each stitching operation, a Work-clamping member carried by the clamp frame and movable relative thereto into and out of operative position to clamp and unclamp the work, thread-clamping means carried by said work-clamping member, and means rendered operative by the relative movement of the frames to clamp the thread in said thread-clamping member at the end of the stitching operation and to release the thread immediately after the formation of the initial stitches of the next succeeding stitching operation.

7. In a sewing machine, the combination with a stitch frame carrying stitch-forming mechanism, of a clamp frame, said frames having a movement relative to each other, a work clamp carried by said clamp frame, two thread-clamping jaws both secured to the work clamp and capable of movement relative to each other, and a clamp-actuating member secured to the stitch frame, relative movement of said frames causing the clampactuating member to move the thread-clamping jaws relative to each other to clamp the thread therebetween at the end of the stitching operation.

8. In a sewing machine, the combination with a stitch frame carrying stitch-forming mechanism, of a clamp frame, said frames having a movement relative to each other, a work clamp carried by said clamp frame, thread-clamping jaws secured to the work clamp, and a clamp-actuating member secured to the stitch frame, relative movement of said frames causing the clamp-actuating member to move the thread-clamping jaws relative to each other to clamp the thread therebetween at the end of the stitching operation and to release the thread immediately after the formation of the initial stitches when the machine is again set in operation.

9. In a buttonhole sewing machine, the combination with a stitch frame carrying stitch-forming mechanism, of a clamp frame, said frames having a movement relative to each other, work clamps pivotally mounted to the clamp frame, thread-clamping jaws secured to the work clamps, one of said aws having a projection associated therewith, and a clamp-actuating member secured to the stitch frame and provided with means which is brought into engagement with said projection during said relative movement at the end of the stitching operation thereby to clamp the thread between said jaws and to maintain operative engagement with saidprojection during the further movement of the frames and until the initial stitches have been formed at the beginning of the stitching operation.

10. In a sewing machlne, the combination with a stitch frame carrying stitch-forming mechanism, of a clamp frame, a work clamp pivotally mounted to said clamp frame, tl'iread-clamping jaws carried by the work clamp, one of said jaws having a projection,

a clamp-actuating member secured to the stitch frame and provided with a cam portion situated to engage said projection when the work clamp is opened and at the end of the stitching operation thereby to clamp the thread and also provided with an extension which acts on said projection. to hold the thread clamped after the work clamp is in operative engagement with the work and until the initial stitches are formed at the beginning of the next stitching operation.

11. Ina sewing machine, the combination with a stitch frame carrying stitch-forming mechanism, of a clamp frame carrying workclamping means, said stitch frame and clamp frame having a movement relative to each other in a direction parallel to the work held by the work-clamping means, a threadclamping device carried by the work-clamp ing means above the work, means actuated by the relative movement of said frames to cause said thread-clamping device to clamp the thread at the end of the stitching operation, and a thread-cutting device associated with said thread-clamping device.

12 In, a buttonhole sewing machine, the combination with a stitch frame carrying stitch-forming mechanism, of a clamp frame carrying work-clamping means, threadclamping jaws carried by the work-clamping means above the work, a clamp-actuating member secured to the stitch frame and operating through the relative movement of said frames to actuate said jaws to clamp the thread therebetween at the end of a stitching operation on a buttonhole and to release said thread after the initial stitches have been formed on the next succeeding buttonhole, and a thread-cutter associated with one of said thread-clamping jaws.

13. In a buttonhole sewing machine, the combination with stitch-forming mechanism, of work-clamping means situated above the work, said stitchforming mechanism and work-clamping means having a relative movement during which the edge stitches of a buttonhole are formed and the parts are moved from stitching position to buttonhole-cutting position, and means carried by said work-clamping means and actuated by said relative movement to clamp the thread at the end of a stitching operation when the stitch-forming mechanism and work-clamping means are in one position relative to each other and to release said thread as the initial stitches of the next succeeding stitching operation are being formed and when the stitch-forming mechanism and work-clamping means are in another position relative to each other. 1

14. In a buttonhole sewing machine, the combination with stitch-forming mechanism, of work-clamping means situated above the work, said stitch-forming mechanism and work-clamping means having a relative movement during which the edge stitches on a buttonhole are formed and the parts are moved from stitching position to buttonhole-cutting position, a pair of thread.- clamping jaws carried by the work-clamp ing means above the work and situated so that the needle thread is carried between them during the relative movement of said stitch-forming mechanism and work-clamp ing means from stitching to buttonholecutting position, and means actuated by said relative movement to close said jaws thereby to clamp the needle thread and to release said jaws thereby to release the thread after the work-clamping means and stitch-forming mechanism have been moved into stitching position.

15. In a sewing machine, the combination with stitch-forming mechanism, of work-clamping uneans situated above the work, said stitch-forming mechanism and work-clamping means having a movement relative to each other in a direction parallel to the work held by the work-clamping means to effect a predetermined cycle of operations including the stitching operation, and a thread-clamping device carried by the work-clamping means and actuated by said relative movement to clamp the thread at the end of the stitching operation.

16. In a sewing machine, the combination with stitch-forming mechanism, of work-clamping means situated above the work, said stitch-forming mechanism and work-clamping means having a movement relative to each other in a direction parallel to the work held by the work-clamping means to efiect a predetermined cycle of operations including the stitching operation, and a thread-clamping device carried by the work-clamping means and actuated by said relative movement to clamp the thread at the end of the stitching operation and to release the thread during the formation of the initial stitches of the next succeeding stitching operation.

In testimony whereof, I have signed my name to this specification.

GLENN COLE.

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

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