US1729241A - Thread-cutting mechanism - Google Patents

Description

Sept. 24, 1929.

J. M. BENJAMIN THREAD CUTTING MECHANISM Original Filed Oct. 28, 1920 4 Sheets-Sheet 1 Sept. 24, 1929. J. M. BENJAMIN 1,729,241

THREAD CUTTING MECHANISM Original Filed Oct; 28 1920 4 Sheets-Sheet 2 Sept. 24, 1929. J. M. BENJAMIN THREAD CUTTING MECHANISM Original Filed Oct. 28. 1920v Sheets-Sheet 5 Sept. 24, 1929. .1. M. BENJAMIN 1,729,241

' THREAD CUTTING MECHANISM I Orglginal Filed Oct. 28, 1920 4 Sheets-Sheet 4 Patented Sept. 24, 1929 UNITED STATES PATENT OFFICE JOHN BENJAMIN, F BEVERLY, MASSACHUSETTS, ASSIGNOR T0 UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEVJ' JERSEY, A CORPORATION OF NEW' JERSEY THREAD-CUTTING MECHANISM- Application fil-ed October 28, 1920, Serial This invention relates to machines for sewing together sections of sheet material and, more particularly, to a thread cutting mechanism for severing the thread after the completion of a seam.

The objects of the invention are to improve the construction and mode of operation of thread cutting mechanisms for machines of this class, and to produce a thread cutting mechanism which is simple in construction, reliable in operation, and which will operate automatically to sever the thread after the completion of a seam.

The invention is illustrated in the present application as embodied in mechanism arranged to sever the thread between articles or sections of material successively stitched upon the machine. It is to be understood, however, that the invention is not limited to this particular mode of operation, but certain features thereof may be embodied in mechanisms operating to sever the thread between the stitch forming devices and the Work.

An important feature of the present invention consists in the provision of means for moving the thread cutting device in the direction of feed with the work while said device is in operation. In the present construction the thread cutting device, when thrown into operation, is given several thread cutting movements and the movement of said device in the direction of feed with the work practically insures the severing of the thread before said device is thrown out of operation.

The thread cutting device of the present machine is mounted for lateral or horizontal movements on a suitable support, and an- 40 other feature of the invention consists in the provision of mechanism for actuating the thread cutting device which is thrown into and out of operation by the lateral movement of the support. The movements of the support are produced and controlled by a work carrier during the movement of the carrier through the machine. In the present embodiment of the invention the movement of the support not only throws the actuating mechanism for the cutting de No. 420,103. Renewed February 14, 1925;.

vice into operation, but also carries the thread cutting device from operative to inoperative position with relation to the thread to be severed. The above feature makes for simplicity in the construction and for lightness and easy running of the parts and enables the thread cutting device to be moved into operative position and to be thrown into operation in a certain and reliable manner with the expenditure of very little force or power.

The invention embodies various other important features, constructions, and combination of parts hereinafter described and particularly pointed out in the claims, the advantages of which will be readily understood and appreciated by those skilled in the art. r

The invention will be clearly understood from the accompanying drawings illustrating the invention in its preferred form, and the following detailed description of the constructions therein shown.

In the drawings Fig. 1 is a view in front elevation of a machine embodying the invention; Fig. 2 is a view in horizontal section of a port-ion of the machine; Fig. 3 is a detail View in side elevation, looking from the left and illustrating the thread severing mechanism and certain associated parts; Fig. 4 is a view in side elevation, looking from the right, of the mechanism shown in Fig. 3; Fig. 5 is a view in front elevation illustrating certain of the parts shown in Figs. 8 and 4; Fig. 6 is an underside plan view of certain parts, of the machine; Fig. 7 is an underside plan view illustrating particularly the thread severing mechanisms; Fig. 8 is a view similar to Fig. 7 illustrating certain of the parts in different positions; and Figs. 9 and 10 are detail views illustrating respectively different parts of the mechanism shown in Figs. 7 and 8 detached from the machine.

The machine illustrated in the drawings has the same construction, arrangement and mode of operation of parts as the machine illustrated and described in the application of Benjamin F. Mayo, Serial No. 368,025, filed March 23, 1920. The machine is especially designed to be employed in sewing a seam along the backedges of the two parts of an upper generally known as the quarters to attach the same together. By making certain relatively slight changes, however, the machine may be fitted for sewing other seams.

The sewing mechanism of the machine is of well-known construction, and comprises a vertically reciprocating straight-eyed needle 2, a presser foot 4 and a feed dog 6. All of these parts are actuated from a main shaft 8. The main shaft 8 is driven by means of a pulley 1O loosely mounted on the shaft and a belt 12 passing about the pulley and about a pulley 14 secured to a driving shaft I To enable the main shaft 8 to be started and stopped at suitable times, a friction hand arm of the lever 18 is held in its rearward position during the sewing operation by the engagement of a spring actuated latch 22 pivoted on the lever with a shoulder 24 formed on an arm on the frame of the machine. After the completion of the sewing operation the latch 22 is thrown out of engagement with the shoulder 24 and the left hand arm of the lever 18 is swung forwardly to cause the disengagement of the clutch by the action of a suitable spring.

In the present machine a series of work clamping carriers is provided, each carrier being constructed to hold two parts of an upper to be sewn together. Each of these carriers comprises a lower clamping plate 26 and an upper clamping plate 28 pivoted to the lower clamping plate by means of a pivot pin 30 and normally held by the force of gravity in closed relation to the lower clamping plate. The carriers illustrated in the drawings are especially constructed for use in sewing quarters, and are provided with gage devices to locate the parts in proper position between the clamping plates. When the quarters are in place between the two clamping plates and the upper clamping plate is closed, the rear margins of the quarters project uniformly beyond the clamping plates which conform to the curve of the quarters as clearly shown in Fig. 2.

The carriers of the present machine lie upon and are movable over the upper surface of a work table 32 and are moved over the table to carry them in succession through the machine, the carriers being held on the table merely by the action of gravity. l/Vhen the work is applied to a carrier the carrier is located at the front of the machine in what will be termed, for convenience, work receiv ing position, the upper clamping plate then being open to receive the parts of the upper. After the work has been placed in a carrier, the carrier is movedfrom work receiving position past the sewing mechanism, guiding devices for the carrier causing the carrier to move in a predetermined path during the sewing operation. After a seam is completed the carrier is moved back in two stages to work receiving position. Upon the completion of each scam, the sewing mechanism is stopped and the carriers come to rest and remain stationary until thenext operation.

The machine illustrated is provided with three work carriers which, when the machine is stopped after the completion of the sewing of a seam, occupy respectively the positions of the carriers A, B, and C, shown in Fig. 2.

The carrier A is illustrated in this figure in work receiving position, the carrier B in the position which each of the carriers assume after a seam is completed through the parts of the upper carried thereby, and the carrier C in the position which each of the carriers assume after the first stage in the bringing of the carrier back to work receiving position.

Vi hen in work receiving position the cari'iers 11 f the table 32, an extension being formed on the table to assist in supporting the carriers, and a. pair of pins 34 mounted on the lower clan'iping plate are engaged in a guiding groove or slot 36 1n said table.

The upper clamping plate is then held in open position by the engagement of a stationary cam plate 38 with a projection 40'on the upper clamping plate. When the parts of the upper have been placed on the carrier the carrier is released and is then moved from work receiving position toward the sewing mecha 'nism by means of a radial projection or arm formed on a rotary disk 44 and arranged to engage one of the pins 34. The disk 44 is rotated to move the carrier from work receiving position upon the release of the carrier by a suitable frictionally acting driving mechanism. When a carrier has been moved into work receiving position, the arm 42is engaged with a rearward or left hand pin in the guidim slot 36, as shown in Fig. 2, and the carrier and the disk 44 are then held from movement by the engagement of the forward pin 34 with the upper end of a vertically movable rod 46. To the lower end of the rod 46 is connected an actuating lever 48 which is norm ally held in elevated position by a spring 50. Then the two parts of the upper have been placed in the work carrier, the operator actu ates the lever 48 to depress the pin 46 and thereby release the carrier. As the carrier is thus released the disk 44 starts to rotate and the carrier is moved from work receiving po* sition toward the stitch forming mechanism by the action of the arm 42. The initial movement of the carrier from work receiving posis tion carries the pro ection 40 out of engagement with the cam plate 38 and the upper clamping plate is then closed on the work by the action of gravity.

The carrier is guided during its movement from work receiving position toward the sewing mechanism by the engagement of the pins 34 in the guide slot 36. The movement of the carrier produced by the disk 44 carries the carrier over a sectional belt mounted on shafts 52 and 5 1 which feeds the carrier through its frictional engagement with the lower clamping plate. The guiding groove 86 terminates some distance forwardly of the sewing mechanism so that the pins 34 are dis engaged therefrom before the seam is started.

During the sewing of the seam the carrier is guided by the engagement of pins 56 and 58 mounted on the upper clamping plate in cam grooves 60 and 61 formed in a block 62 secured to the frame of the machine, these cam grooves being constructed to impart the proper angular movements to the work carrier to cause the needle to operate along a line substantially parallel with the reversely curved back edges of the quarters secured in the carrier.

As the carrier approaches the sewing mechanism a block 64 mounted on the upper clamping plate engages a roll 66 carried by a vertical movable rod 68 and lifts the rod. The rod 68 controls. through certain connections, the mechanism for swinging the left hand arm of the lever 18 rearwardly to engage the clutch for connecting the pulley 10 with the shaft 8, this mechanism being thrown into operation by the vertical movement of the rod. The

lever 18 is held in position during the sewing operation by the engagement of the latch 22 with the shoulder 24. During the sewing operation the work is fed by the action of the feed dog 6 and the carrier is advanced by the action of the feed belt 50 and by the action of feed rolls 7 0 and 72 which are mounted below the table 32 and project slightly above the table so as to engage frictionally the lower clamping plate. hen the seam has been completed, the latch 22 is disengaged from the shoulder 24 allowing the left hand arm of the lever 18 to be swung forwardly by its actuating spring to disengage the driving clutch for the shaft 8 by the engagement of a pin 74. carried by the upper clamping plate of the carrier with the rear end of the latch.

The sewing mechanism is preferably stopped with the needle in the work adjacent the lower edge of the quarters, as shown in Fig. 2, and the part of the work carrier which is then at the left continues to be advanced by the feed rolls 70 and 72 thereby swinging the carrier. about the needle as a fulcrum into substanti ally the position of the carrier B, so that when the carrier finally comes to rest it will be out of the way of the succeeding carrier. To permit this movement of the carrier the rear portion of the right hand wall of the groove 61 is formed on a lever 7 6 pivoted at 78 on the block 62. As the left hand arm of the lever 18 is swung forwardly upon stopping the sewing mechanism, the lever 76 is lifted to disengage this part of the wall of the cam groove 61 from the pins 56 and 58 by the engagement of the lever 18 with a projection 80 on the lever 76. i

As the sewing mechanism is started, the carrier containing the parts of an upper upon which the sewing operation has just been completed and which then occupies the position of the carrier B, Fig. 2, is released by the disengagement of the needle from the material, and the thread between the work carried respectively by this carrier and the succeeding carrier is severed by a thread severing mechanism. The latter carrier is then fed rearwardly first by the action of feed roll 72 and then by the action of feed rolls 82 mounted below the table 32 and projecting upwardly through slots in the table so as to engage frictionally the lower clamping plate, similarly arranged anti-friction rolls 84: and 86 being provided to enable the carrier to be fed readily. This brings the latter carrier into substantially the position of the carrier C, Fig. 2, the carrier stopping at this point because of the fact that it is carried out of the range of action of the feed rolls 82.

During the movement of a carrier from the position of the carrier to the position of the carrier B, and the movement of another carrier from the position of the carrier B to the position of the carrier C, the third carrier, which occupied the position of the carrier C, is carried forwardly into work receiving position. The mechanism for thus actuating the third carrier is fully described in the Mayo application referred to above and need not be described in the present application.

After a carrier starts to move from the position of the carrier B away from the sewing mechanism, and after a seam is started .in the parts of an upper secured in the succeeding carrier, the thread extending "etween these parts and the parts secured in the preceding carrier is severed automaticat ly. The mechanism for severing the thread comprises a lever 88 secured to one end of a rock shaft 90 and a thread cutting knife 92 mounted on the lever. The rock shaft 90 is mounted to turn in a bearing in a support 94 secured to the lower end of a rod 96 which is supported at its upper end to swing in any direction by a universal joint 97. The thread cutting knife is thus supported so that it may be moved forwardly and rearwardly and laterally of the machine. The rock shaft 90 is acted upon by a coiled spring 98 which tends to turn the shaft in a direct-ionto retract the thread cutting knife. The rod 96 lid is acted upon by a coiled spring which tends to swing the same and the thread cutting knife forwardly or opposite to the feed and toward the right, Fig. 1, and maintains the knife normally in the position shown in Fig. 7, the movement of the support 9 1 and the knife, toward the right under the action of the spring being limited by the engagement of a pin 102 mounted on the support with a ledge 10st formed on a bracket 106 secured to the frame, and their forward movement being limited by the engagement of the pin with a shoulder 108 located adjacent the forward end of said ledge.

As one carrier is carried away from the sewing mechanism after the completion of a scam in the parts of an upper carried there by, and after a seam is started in the parts carried by the succeeding carrier, the thread cutting knife is moved rearwardly with the carriers and to the left by the movement of the second carrier into position to engage the thread between the two sets of upper parts carried by the respective carriers. and the. knife lever 88 is then rapidly oscillated to cause the knife to sever the thread. The knife is moved rearwardly by the carriers at the proper time by the engagement of a pin 110 mounted on each of the carriers with a latch 112 pivoted at 114 on the support 9st. During the rearward movement thus imparted to the support, the support is moved to the left by the engagement of the pin 102 with a switch cam 116 pivoted at 118 on the bracket 106. The switch cam is normally held by a spring 120 in the inclined position shown in 7 and 8 with the free end thereof in engagement with the ledge 10 1. When in this position as the support 94 is moved rearwardly the pin 102 engages and is carried along the face of the switch cam and the support is thereby moved to the right in F ig. 7 or left in Fig. 2. This movement of the support carries the knife into the position shown in Fig. 8. As the pin 102 passes beyond the switch cam the spring 100 moves the support to the left in Fig. 8 and the latch 112 is then swung on its axis to disengage the same from the pin 110 by the engagement with the latch of a pin 122 secured in the bracket 106. The spring 100 then moves the support 91 forwardly to its normal position. the switch cam 116 yielding and allowing the pin 102 to pass.

The knife lever 88 is actuated to oscillate the knife by means of a pin 124 formed on a bracket secured to the needle bar and engaging in a slot 120 in the knife lever. The knife lever, when the support 9% is in its normal position, is locate-c. in the angular position shown in Fig. 1 and in full lines in Fig 5, the slot 120 then lying substantially parallel with the direction of reciprocation of the pin 12 1. lVith the lever in this position, the pin 12 1 reciprocates idly in the slot 126.

The movement of the support 94 to the left, however, causes the knife lever to assume a position in which the slot lies at an angle to the direction of movement of the pin 12 1 so that the lever is then oscillated by the recip ried by the preceding carrier. The knife thus makes several cutting strokes at the same point in the thread and the severance of the thread is practically insured.

The driving mechanism for the disk 14:, the belt 50 and the feed rolls 70, 7 2, and 82 is lv described in the above Mayo applicam, and a description of the same is unnecesfor an understanding of the present inmtson. The disk 4/1- is driven intermittently in the manner above described. The feed belt 50 and the feed rolls T0, 7 2, and 82 are driven continuon. y through suitable connections from the main oriving shaft 16.

Hm ilained the nature and object of I and having specifically dem chine en'ibodying the invenform, what claimed is:

l. A machine for sewing together sections o? sheet terial having, in combination, stitch 'l'ornnng mechanism, a thread cutting "ice, mechanism for actuating the cutting "'cc, and a movable work carrier arranged y the cutting device with it from in-. operative to operative position with relation to the thread to be severed and to throw the actuating mechanism into operation during in movement wi h the carrier.

2. A niachine for sew' ig together sections of sheet material havin in combination, st g-ch forming mecl'ianism, a thread cutting device movable in the direction of the feed, and a work carrier bodily n'lovable with the work during the formation of a series of stitches a nged to carry the cutting device in the direction of the feed while said device is operated to cut the thread.

3. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism, a series of movable work carriers each provided with means for embracing a plurality of sections of sheet material and holding them in superposed relation, means for moving the carriers successively past the stitch forming mechanism, a thread cutting device, and means on each of the carriers for controlling the operation of the thread cutting device.

4-. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism, a series of unconnected carriers each provided with means for retaining the plurality of sections of sheet material in superposed relation, means for moving the carriers successively past the stitch forming mechanism, a thread cutter, and means on each carrier for throwing the cutter into operation to cut the thread between that carrier and the next preceding carrier.

5. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism, a series of work carriers, a thread cutter for cutting the thread between the carriers, and means for throwing the cutter into and out of opera tion and for giving it several thread cutting movements in each cutting operation.

6. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism. a work carrier, means for moving the work carrier pastthe stitch forming mechanism, a thread cutter, and means for bringing the cutter into cutting relation to the thread and for giving it several cutting movements in each cutting operation.

7. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism, a series of work carriers, means for moving them in succession past the stitch forming mechanism, a thread cutter for cutting the thread between the carriers, and means for rendering the cutter active on the thread and for giving it several thread cutting movements in each cutting operation. 7

8. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism, a thread cutting device, a movable work carrier arranged to carry the thread cutting device with the work during the cutting operation of the cutter on the thread.

9. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism, a series of movable carriers for such material, means for moving the carriers in succession past the stitch forming mechanism, a device for severing the thread between the parts of the work carried by successive carriers, and means on the carriers for moving the thread severing device in the direction of feed with the carriers and for shifting said device transversely of the direction of feed to throw the same into operation.

10. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism, a series of movable carriers for such material, means for moving the carriers in succession past the stitch forming mechanism, a device for severing the thread between the parts of the work carried by successive carriers, means on the carriers for moving the thread severing device in the direction of feed with the carriers, and mechanism for actuating said destitch forming mechanism, a movable carrier for such material, a thread severing device, a movable support for the thread severing device, means on the carrier for moving said device in the direction of feed, a switch for shifting said device laterally during this movement, arranged to allow the return of said device after a predetermined movement thereof, mechanism for disconnecting said device from said means, and a spring for returning said device to its initial position.

12. A sewing machine having, in combination, stitch forming mechanism, a thread severing device movable in the direction of feed and in a direction transverse thereto in a plane substantially parallel to the plane of the work, mechanism for moving the thread severing device in the direction of feed with the Work, and means for moving said device in a direction transverse to the direction of feed in a plane substantially parallel to the plane of the work during its movement in the direction of feed to throw the same into operation, to cut the thread 13. A sewing machine having, in combination, stitch forming mechanism, a thread cutting knife, a pivoted knife carrier, a reciprocating member, a pin mounted on said member, a slot formed in the knife carrier in which said pin engages, means normally maintaining the knife carrier in position with the slot parallel to the direction of reciprocation of said pin, and means for moving the carrier to locate the slot at an angle to the direction of reciprocation of said pin, and thereby cause the pin to oscillate the knife carrier and knife.

14. A sewing machine having, in combination, stitch forming mechanism, a thread severing knife, a pivoted knife carrier, a reciprocating member, a pin mounted on said member, a slot formed in the knife carrier and arranged to receive the pin, a support movable in a direction transverse to the direction of feed on which the knife carrier is pivoted, means for maintaining the knife carrier in position with the slot substantially parallel to the direction of reciprocation of the pin, and means for moving the knife carrier in a direction transverse to the direction of feed to place the slot at an angle to the direction of reciprocation of the pin. and thereby cause the oscillation of the knife carrier and the knife and to locate the knife in position to sever the thread.

15. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism, a movable carrier for such material, a thread severing device, a movable support for said device, means on the carrier for moving the support to carry said device in the direction of feed, and a switch for shifting the support during the movement of the support in the direction of feed to move said device in a direction transverse to the direction of feed.

16. A sewing machine having, in combination, stitch forming mechanism, a thread severing device, means for moving said device in the direction of feed with the work, and means for imparting an additional movement to said device to sever the thread during the movement of said device in the direction of feed.

17. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism, a movable carrier for such material, a thread severing device, a movable support for said device, means on the carrier for moving the support with the carrier, and a switch for guiding the support during its movement.

18. A machine for sewing together sections of sheet material having, in combination, stitch forming mechanism, a thread cutting device, a work carrier provided with means for holding thereon a plurality of such sections and arranged to carry the cutting de vice in the direction of the feed while said device is operated to cut the thread, said carrier being bodily movable with the work during the formation of a series of stitches.

19. A sewing machine having, in combination, stitch forming mechanism, a thread cutting device and a movable work carrier arranged to carry the cutting device with the work while said device is operating to cut the thread, said carrier being bodily movable with the work during the formation of a series of stitches. I

JOHN M. BENJAMIN.

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