US1001034A - Thread-controlling mechanism for sewing-machines. - Google Patents

Description

v 0. M. HORTON. THREAD CONTROLLING MECHANISM FOR SEWING MACHINES.

APPLICATION IILED MAB.5, 1909.

Patented Aug. 22, 1911.

I\ a SHEETS-SHEET 1.

INVENTOR WITNESSES ATTORNEY C. M. HORTON.

THREAD CONTROLLING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED MALE, 1909.

1,001,034. Patented Aug. 22, 1911.-

I alum :mm l W WITNESSES NTOB [NV 7; g 5144,4711. vk

Jay 7 z; ATTORNEY G. M. HORTON. THREAD CONTROLLING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED MAR. 5,1909

Patented Aug. 22, 1911.

3 SHEETS-SHEET 3.-

ATTORNEY COLUMBIA PLANOGRAPII (20., WASHINGTON. n. c.

CHARLES M. HORTON, 0F ELIZABETH, NEW JERSEY, ASSIGNOR TO THE SINGER MANUFACTURING COMPANY, A CORPORATION OF NEW JERSEY.

THREAD-CONTROLLING MECHANISM FOR SEWING-MACHINES.

To all whom it may concem:

Be it known that I, CHARLES M. HORTON, a citizen of the United States, residing at Elizabeth, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in Thread-Controlling Mechanism for Sewing-Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to an improvement in that class of sewing machines for produc ing detached groups of stitches, in which means are provided for severing the threads at the completion of each group of stitches; and it is designed more particularly for embodiment in the machine forming the subj ect of my United States Patent No. 807,676, dated December 19, 1905, and in my pending application Serial No. 340,826, filed October 27, 1906.

The invention has for its primary object to provide means for so handling the needlethread during the performance of the initial stitch-forming cycle of a series as to permit the use of a single-grooved needle without liability of breaking the thread in operating upon close-textured or hard fabrics, or those of such character that the thread end is clamped firmly between the surface of the needle and the adjacent wall of the needle puncture in the fabric during the descent of the needle to present a loop to the looptaker. In the mechanism disclosed in my said pending application, provision is made upon the lower end of the needle-bar for gripping the needle-thread preparatory to its descent for the initial stitch of a series and maintaining it gripped until the needle rises. lVhile this is practicable with the use of a double-grooved needle, through the rearward groove of which the end portion of the needle-thread may be drawn while the needle is in the work by the action of the shuttle, it is inexpedient for the stitching of the heavier materials of close texture, as the provision of a second longitudinal groove in the needle weakens the latter to such degree that it is liable to break in puncturing the material, while, as will be observed, the use of a single-grooved needle causes the clamping of the thread end between the ungrooved surface of the needle and the more or less rigid wall of the initial Specification of Letters Patent.

Application filed March 5, 1909.

Patented Aug. 22, 1911.

Serial No. 481,359.

needle puncture during the descent of the needle, so that the needle-thread remains nipped on both sides of the eye While requiring increased length as the needle descends beneath the Work, thereby causing breaking of the thread.

The terms single-grooved and doublegrooved as applied herein to the needles are thus used by the trade to designate needles having grooves upon one or both sides extending from the eye along the blade to the enlarged shank by which they are secured in their sockets in the needlebars. The needle represented in Fig. 8 is of the first-named class, although upon what is commonly called the ungrooved side it has a longitudinal recess extending from the needle-eye upward to afford clearance for the thread at the eye so as to prevent the crushing of the thread where it emerges from the eye and its consequent severing as the needle passes through the work.

By the present improvement, the twostage cam for actuating the thread-nipping device is replaced by two distinct cam recesses spaced apart by an intermediate portion adapted 'to maintain the nipper inactive while the needle-eye is below the face of the work. By this means, while the thread-end extending from the needle-eye upon the loop-seizing side of the needle is subjected to the above described nipping action between the needle and the work, the thread upon the opposite side of the needle is free to be drawn down through the needlegroove from the supply given up by the take-up during the descent of the needle, so that the objectionable strain upon the needle-thread is entirely avoided, while the needle is of such form that it may be made sufiiciently strong to effectively perform its work in puncturing the goods.

The present improvement also comprises certain other features which will be hereinafter described and set forth in the claims.

In the drawings, Figure 1 is a rear side elevation and Fig. 2 a bottom plan of a fiat button sewing machine of the Singer type embodying the present improvements. Fig. 3 is a perspective view representing the stitch-forming and thread-nipping and severing devices. Fig. 4 is a plan View and Fig. 5 a rear side elevation of the shuttle and its race with the thread-clampingand severing devices associated therewith. Fig. 6 is abottom view of the throat-plate of the machine and Fig. 7 is a perspective view of the stationary thread-clamping member. Fig. 8 is an enlarged sectional view showing the relation of the thread with the needle in its descent through the material for the initial stitch of a series.

As herein represented, the machine comprises the needle 1 carried by the vertically reciprocating needle-bar 2 operated from the driving shaft 3 which is journaled in the upper part of the arm 4, and an oscillating shuttle 5 fitted within the shuttlerace 6 depending from the bed-plate 7 and deriving its operative movements from the shuttle-driver 8 connected, through the oscillating shaft 9 to the driving shaft 3, which latter is shown provided with the loose pulley 10 and fast pulley 11, the fast pulley having an integral or rigidly attached stop-motion cam 12. Pivotally mounted at its lower end in a projection 13 from the upright portion 14 of the bracketarm is a start and stop-motion lever 15 provided with a belt-shifter 16 and with the springpressed plunger 17, said lever being adapted to assume its rearward or operative position under the action of a spring, and being detained in forward or inoperative position by. a detent lever 18 fulcrumed at 19 and maintained normally in operative engagement with the upper portion of the stop-lever 15 by means of the spring 20 in a manner well-known. The stop-lever 15 is so mounted within the projection 13 as to be capable of a slight sidewise motion which is yieldingly resisted in the stitching operations by the spring-pressed plunger pin '21, represented in end view only in Fig. 1.

As herein shown, the superposed tapered blades 22 and 23 are fixed upon an arm 24 attached to a sector-gear 25 which is journaled upon a pin 26 within a bracket 27 attached to the shuttle-race cover-plate 28. Meshing with said sector-gear is a rack 29 formed upon a lateral arm 30 carried by the sliding bar 31 supported beneath the work-plate of the machine and having near its rearward end the block 32 with lateral notch 33 entered by the contracted lower end 34 of the lever 35 pivotally mounted upon the fixed fulcrum-stud 36 carried by the bracket 37 attached to the bed-plate 7 and provided at its upper end with a pin or roller-stud 38 entering the cam-groove 39 in the rearward face of the rotary camwheel 40 mounted upon the fixed fulcrumstud 41 carried by the frame of the machine. The cam-wheel 40 has attached to its forward side, as indicated in dotted lines in Fig. 1, the worm-wheel 42 meshing with the worm 43 fixed upon the main-shaft 3. The block 32 has a rearward extension carrying a pin or roller-stud 44 embraced by the forked arm 45 of a bellcrank-lever fulcrumed at 46 and having a second arm 47 provided with a spring-pressed pin 48 entering the slot 49 in the lower end of the stop-lever 15. V

The two levers 35 and 45 47 serve, through the connections above described, to impart a plural-stage movement to the thread-cutters at the end of each series of stitch-forming operations, whereby needle and shuttle threads are positioned for severing during the final stitch-forming cycle of the series, and are severed by the lateral overthrow of the stop-lever in the final stopping of the moving parts, all as more fully explained in my prior Patent No. 807,676 before mentioned.

Rigidly attached to the arm 24 which carries the upper-thread cutting blade 22 and lower-thread cutting blade 23 is a segmental thread-clamping arm 50 formed with a hooked or barbed outer end 51 pref erably arranged at the level of or slightly above the point of the lower-thread severing blade 23. Adjustably attached to the front face of the shuttle-race 6 by means of fastening screws 52 entering elongated apertures 53 in its shank portion 54 is a stationary spring-clamping blade 55 whose forward operative edge is preferably formed with a. thread notch 56 and spaced slightly beneath the slide-plate 28 and adjacent the path of reciprocation of the needle. The stationary blade 55 is arranged to overlie the barb-pointed movable blade 50, and the vertical adjustment afforded by the fastening screws 52 and apertures 53 in the shank 54 permit it to be raised and lowered so as to vary the yielding pressure which it exerts upon the practically rigid movable member 50 in drawing the needle-thread into the notch 56 and between the adjacent faces of the clamping members in the initial stitchforming cycle of a series. As will be observed, the notched operative end portion of the blade 55 is in practice inclined clownwardly from the junction of the blade with its shank 54 in order to provide clearance for the body of the rigid clamping blade 50 in performing its operative movements with the cutting blades.

As described in my prior Patent No. 807,676, the needle-bar is provided at its lower end with a thread-nipper comprising a tension plate 57 attached thereto by means of a fastening screw 58 and provided with a thread-guiding slot 59 through which latter the thread passes between the lower end of the plate 57 and needle-bar 2 to the needle. The needle-bar also carries a lateral stud 66 upon which is pivoted a lever 61 whose lower end bears upon the lower portion of the tension plate 57, and whose upper arm is adapted to be engaged by an arm 62 secured upon the forward end of a reciprocating rod 63 connected at its rearward end with a depending arm 64 of a bellcrank-lever pivoted at 65 upon the bracket-arm and having the outer end of its lateral arm 66 formed with a tooth 67 which is pressed normally upon the periphery of the cam-wheel 4:0 by means of a spring 68. The cam-wheel 40, which is shown in the drawings formed with three sets of cam-paths so as to produce three distinct series of actuations of he connected parts for each rotation of the cam, has three pairs of peripheral recesses or depressions 69 and 70, with intermediate concentric peripheral portions 71, having a path of circular movement beneath the point of the tooth 67. The concentric peripheral portions 71 intermediate the jogs or depressions 69 and 70 are at the same distance from the axis of the cam-wheel 4:0 and have the same curvature as the longer circular port-ions between the closely spaced jogs or depressions, and hence their action upon the tooth 67 constituting the cam-fob lower is precisely the same as that of the longer circular peripheral portions. The relative depths of the cam recesses 69 and 70 correspond with those of the two connected pairs of the single double-stepped peripheral recesses described in my pending application Serial No. 340,826, in producing an initial drag on the thread during the cutting operation and a subsequent nipping action of greater intensity in the succeeding initial stitch-forming cycle; but they difi'er therefrom in being entirely separate and independent, so as to produce two distinct nipping actions of the plate 57 upon the needle-thread instead of a single twostepped action, the concentric peripheral cam-portion 71 being of such extent as to insure the inaction of the clamping plate 57 upon the needle-thread during the period of the reciprocation of the needle in which its eye is below the work, whereby the thread whose free end is nipped between the surface of the ungrooved side of the needle and the adjacent wall of the needle puncture in the work is adapted to accommodate itself to the descending movement of the needle by drawing upon the supply given up by the take-up through the grooved side of the needle.

The conditions referred to are indicated in Fig. 8 in which the end portion a of the needle-thread a is shown jammed between the adjacent wall of the needle puncture in the material on and the ungrooved side of the needle 1, while that portion of the thread extending from the needle-eye 1" upwardly through the long groove 1 in the opposite side of the needle-blade is free to move within the needle puncture to supply the increased length of thread below the work demanded by the continued descent of the needle.

As the needle starts to rise to throw out its loop, the latter is seized in the usual manner upon the ungroovedside of the needle by the point of the shuttle, and may be freely expanded by the same while the eye of the rising needle is still below the work, the additional thread required being readily 1 drawn through the long groove 1 in the side of the needle-blade for the purpose.

The face-plate 72 of the bracket-arm is provided with the usual lug 74 carrying the tension disks 75 which are mounted upon the usual threaded pin 7 6 having upon its outer end the nut 77 between which and the outer tension disk is interposed the spring 78. The tension device is provided with the usual check spring or slack thread-controller having a radial arm 79 with thread-engaging loop 80. In threading the machine, the needle-thread a is led from the source of supply through the usual guide in the faceplate downwardly between the tension disks 75 around the pin 76 and upwardly over the guide-wire 81 and through the guide-loop of the check spring 7 9 to the eye of the take-up 82, whence it is led downwardly through the usual guide-eye 83 into the slot 59 beneath the lower portion of the tensionplate 57 to the needle-eye.

As herein -represented, the machine is provided with a traveling work-clamp comprising the fiat lower member 84 and the upper button holding member 85 yieldingly supported upon the block 86 which is mounted upon the clamp-lever 87 having its rearward end fulcrumed upon a block 88 fitted to a slide-way 89 formed in the bed-plate 7 of the machine, and provided with wellknown means (not shown) for imparting to the work-holder jogging movements longitudinally of the machine. The sidewise movements of the work-holder are derived from the cam-wheel 40 which is provided with the cam-groove 90 entered by the roller-stud 91 upon the upper arm of the rock-lever 92 mounted upon a fixed fulcrum 93 and having its lower end adjustably connected beneath the bed-plate by means of the pit-man 94 with the lateral arm 95 of a bellcrank-lever fulcrumed at 96 upon the under side of the bed-plate and having a longitudinal arm 97 connected by means of the bent link '98 with a stud 99 carried by the slide-plate 100 connected by means of screws 101 passing through clearance apertures in the bed-plate with a slide-plate 102 attached to the clamp-lever 87. When the machine is at rest after the completion of a stitching operation, the needle is in a position slightly lower than its highest position, the thread-cutting blades 22 and 23 and movable nipping blade 50 being in the advance positions which they assume when partially retracted after the final stage of the previous cutting operation, as repre sented in Fig. 4:. In this position of the parts, the tooth 67 of the bellcrank-lever arm 66 rests in the bottom of the shallower cam recess 69, and the needle-thread is lightly gripped by the tension-plate 57 so as to overcome the action of the check spring or slack thread-controller adjacent the tension device so as to prevent its pulling the severed needle-thread end out of the needleeye at the time the needle-thread is cut by the sharpened portion 22 of the upperthread cutting blade 22 in its final advance under the lateral overthrow of the stoplever 15 at the end of the final stitch-forming cycle of the series. The initial nipping action of the tension-plate 57 occurs just prior to a thread-severing operation and during the final upward movement of the take up, the object of the initial drag thus produced upon the needle-thread being to prevent the 'unthreading of the needle due to the elasticity of the thread between the take-up and the point where the thread is severed, or the action upon the thread of the check spring permitted by the cutting operation.

As the machine is started, the needle begins to descend, and just about as its eye passes through the work, the point of the tooth 67 of the nipper-controlling bellcranklever rides up the inclined end of the cam recess 69, whereby the pressure of the lever 61 upon the tension-plate 57 is relieved and the needle-thread is permitted to pass freely through the same to the needle. As the needle continues to descend, it passes between the barb 51 of the clamping blade 50 and the notched forward end 56 of the stationary nipping blade 55, the thread assuming the position represented in Fig. 8 in relation to the needle and the material. As the needle begins to rise, the thread-loop thus formed is seized by the point of the shuttle and expanded sufficiently for the latters passage through the same, slack being provided for such operation by the partial descent of the take-up arm in this stage of the stitch-forming cycle. In this operation, especially with threads having a glaze, or those of a wiry nature, the rubbing act-ion to which the thread adjacent the cut end is subjected by the shuttle while the thread is maintained more or less taut beneath the work serves to obviate to a large degree the liability of kinking which would otherwise render the final clamping action of this stitch-forming cycle uncertain.

The thread-nipper having remained open while the eye of the needle was beneath the work, the point of the tooth 67 now rides down the inclined forward end of the deeper cam recess 70 and again closes the nipper firmly upon the needle-thread just about as the needle-eye emerges from the work, the

continued rise of the needle drawing upward the thread depending from the needle eye within a closed aperture formed by the throat of the barb 51 of the clamping arm 50 and the notch 56 in the forward edge of the stationary clamping blade 55, the knife-actuating mechanism having in the meantime partially retracted the cutting members, with the supporting arm 24, into the position represented in Fig. 3, thereby loosely embracing the end portion of the needle-thread. In practice, the needle reaches its highest position a little before the take-up reaches its highest or stitchsetting point, and in order that the latter may be perfectly free to perform its normal function, the thread-nipper is caused to open at about the time the needle reaches the end of its up-stroke. Just as the takeup reaches its highest position, the throat of the barb 51 moves under the forward edge of the stationary clamping blade 55 and nips the needle-thread close to its cut end where it is firmly held under the same conditions as if it were attached to the material while one or more initial stitches are formed in the latter, after which the continued return movement of the cutting blades and movable clamping blade to initial retracted position takes place and the thread end is released by passage of the throat of the barb 51 over the edge of the clamping blade 55 or over the extremity of the thread.

In the last described positions of the cutting and nipping members, the production of the remaining stitches of the series is effected until the advance of the needle-thread seizingand severing blade 22 just before the beginning of a final stitch-forming cycle, when the severing operations before described are repeated.

It will be observed that each stitch-forming cycle terminates in the setting of the stitch by the take-up arm as the latter reaches its highest position, and that while the initial drag produced by the tensionplate 57 upon the needle-thread occurs prior to the setting of the stitch in the final stitchforming cycle of each group or succession, the succeeding nipping action of the tension-plate occurs prior to the stitch-setting action in the initial stitch-forming cycle in the production of the preceding group or sucession.

The thread-clamp beneath the work afforded by the members 50 and 55 is necessarily somewhat sensitive in order to produce the necessary degree of pressure upon the cut end of the needle-thread without crushing the same, and it is therefore desirable that some relative adjustment be provided in order to insure a uniform clamping action upon threads of different thickness, and this is afforded by providing suitable means of adjustment for the shanlc clamping means may be increased to cover a larger range of movement in case the movable blade 50 should be made elastic, as formerly, so that both blades will yield and thus accommodate threads of different sizes without material variation in the clamping tion with closely spaced but independent acpressure applied to the thread.

Having thus set forth the nature of the portion corresponding in effect upon said invention, what I claim herein is 1. In a sewing machlne, the combination with stitch-forming mechanism including a reciprocating thread-carrying needle and acooperating loop-taker, a tension device, a thread-cutter, automatically acting means I for imparting to said thread-cutter a single cutting action for a series of stitch-forming '1 cycles, and a needle-thread clamp with auto- 5 matically acting means for causing it to grip the needle-thread end below the work" in the initial stitchforming cycle succeeding a thread-cutting operation, of a threadnipper reciprocating with the needle-bar and normally inactive in the production-of a succession of stitches, and automatically acting means for imparting to the same a plurality of independent thread-nipping actions in the consecutive stitch-forming cycles including and succeeding each threadcutting operation with an intermediate period of release continuing while the needleeye is below the work.

2. In a sewing machine, the combination with stitch-forming mechanism including a reciprocating thread-carrying needle and a cooperating loop-taker, a tension device, a take-up, a thread-cutter, and a needle thread clamp with automatically acting means for causing it to grip the needle-thread end below the work in the initial stitch-forming cycle succeeding a thread-cutting operation, of a thread-nipper reciprocating with the needle-bar and disposed intermediate said tension device and the needle, a slack-threadcontroller intermediate the tension device and said thread-nipper, and automatically acting means for operating said thread-nipper to impose a drag upon the needle-thread when the latter is severed and in the initial stitch-producing operation thereafter to re lease the thread while the needle is in the material and to subsequently firmly clamp with stitch-forming mechanism including a reciprocating thread-carrying needle and a cooperating loop-taker, a tenslon device, a

take-up, a thread-cutter, and a needle-thread clamp with automatically acting means for causing it to grip the needle-thread end below the work in' the initial stitch-forming cycle succeeding a thread-cutting operation, of a thread-nipperintermediate said tension device and the needle, a slack-thread-controller intermediate the tension device and said thread-nipper, a cam-follower, a connection intermediate said follower and the thread-nipper, and a rotary cycle-cam in operative relation with said follower and hav ing a substantially circular operative portive portions and an intermediate inactive operation, while remaining inoperative for a portion of a stitch-forming cycle intermediate said actuations' 4. In a sewing machine, the combination with stitch-forming mechanism including a reciprocating thread-carrying needle and a cooperating loop-taker, a tension device, a take-up, a slack thread controller intermedi ate the tensiondevice and take-up, a threadcutter, and automatically acting means for imparting to said thread-cutter an operative advance movement in the final stitch-forming cycle of a series and a return movement in the initial stitch-forming cycle of a subsequent series, of a movable thread-clamping blade rigidly connected with. and deriving operative movements from said thread-cutter and having an operative portion movable across the path of reciprocation of said needle, a stationary spring-clamping blade mounted upon a fixed support and cooperating with said movable clamping blade in gripping the needle-thread subsequent to a cutting operation, a thread-nipper intermediate the tension device and the needle, and a rotary cam having a path and a follower therefor with connections to said outter for imparting the said advance and return movements to the latter, and a second path comprising a substantially circular portion with spaced jogs and a follower there-- to said thread-cutter a single cutting action ing an operative movement to the movable thread-clamping member in the initial stitch-forming cycle immediately succeeding a thread-cutting operation.

6. In a sewing machine, the combination With stitch-forming mechanism including a reciprocating thread-carrying needle and a cooperating loop-taker, of a thread-cutter, automatically acting means for imparting to said thread-cutter a single cutting action in a series of stitch-forming cycles, a stationary thread-clamping blade adjustably mounted upon a fixed support and having an operative port-ion adjacent the needlepath, a thread-clamping member provided With a thread-engaging shoulder and movable in rubbing contact With said stationary blade, and automatically acting means for imparting an operative movement to the movable thread-clamping member in the initial stitch-forming cycle immediately succeeding a thread-cutting operation.

7. In a sewing machine, the combination With stitch-forming mechanism including a reciprocating thread-carrying needle and a' circularly moving shuttle, and a shuttle-race in Which said shuttle is mounted to operate, of a thread-cutter, a carrier therefor, automatically acting means for imparting to said thread-cutter a single cutting action in a series of stitch-forming cycles, and a return movement thereof in the stitch-forming cycle immediately succeeding that in Which said cutting action occurs, a stationary thread-clamping spring-blade secured upon said shuttle-race and having an operative portion adjacent the needle-path, and a thread-clamping member provided with a thread-engaging shoulder and fixed upon the cutter-carrier to move therewith in rubbing contact With said stationary thread-clamping blade. r

In testimony whereof, I have signed my name to this specification, in the presence of tWo subscribing Witnesses.

CHARLES M. HORTON. Witnesses:

VIoToR E. SMITH, HENRY J. MILLER.

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

' Washington, D. C.

Images