US2310176A - Needle-vibrating mechanism for sewing machines - Google Patents

Description

1=eb. 1943. ANHALE 2,310.1"

NEEDLE-VIBRATING MECHANISM FOR SEWING MACHINES Filed May 9, 1941 4 Sheets-Sheet 1 A. N. HALE NEEDLE- VIBRATING MECHANISM FOR SEWING MACHINES Filed Mays, 1941 4 Sheets-Sheet 2 gin/0W L/Zrthur L/l fJfaZe Feb. 2, l943.- A. N. HALE NEEDLE-VIBRATING MECHANISM FOR SEWING MACHINES v Fileqi May 9, 1941 4 Sheets-Sheet E mo" Feb. 2, 1943. A N, HA E v 2,310,17

NEEDLE-VIBRATING MECHANISM FOR SEWING MACHINES Filed May 9 194] 4 Sheets-Sheet 4 I v l ll llllllllllllllllll Qqrthwr av: Ofale cla Patented Feb. 2, 1943 NEEDLE-VIBRATING MECHANISM FOR SEWING MACHINES Arthur N. Hale, Bridgeport, Conn., assignor to The Singer Manufacturing Company, Elizabeth, N. J a corporation of New Jersey Application May 9, 1941, Serial No. 392,685

24 Claims.

This invention relates to needle-vibrating mechanisms for sewing machines and has for an object to provide a high speed needle-vibrating mechanism effective to maintain the needle substantially free from lateral movement while entering and leaving the work. The invention also has for an object to provide a needle-vibrating mechanism adapted for operation at high speeds and for the production of wide bight zig zag stitch seams.

A further object of the invention is to provide a needle-vibrating mechanism whichmay be conveniently and accurately regulated to control the reciprocation of the needle in different and in variably spaced paths in the production of ornamental stitching effects.

It has been a common practice in sewing machines of prior construction to employ irregular cams for transmitting lateral movements to endwise reciprocatory needles against lateral movement while in the work. Cams employed for this purpose are a definite speed-limiting factor, are subject unduly to wear, and are noisy. To provide for higher speeds of operationof the machine, it has also been common to impart lateral vibratory movements to a needle by means of an actuating eccentric, regardless of the fact that the continuously vibrated needle has been thereby moved laterally while entering and leaving the work.

For certain classes of work it is undesirable to impart any substantial lateral movement to the needle while entering and leaving the work, and the present invention aims to provide needlevibrating mechanism which has the advantage of being adapted for high speed operation and, nevertheless, properly controlling the lateral movements of the needle.

Other and more specific objects of the invention will be apparent from the following description and claims.

The invention consists in the devices, combinations and arrangements of parts hereinafter described in connection with the accompanying drawings which illustrate a preferred embodiment of the invention and in which:

I Fig. 1 is a vertical longitudinal section of a sewing machine containing the improved needlevibrating mechanism. Fig. 2 is a bottom plan view of the machine. Fig. 3 is an enlarged, substantially vertical section transversely of the bracket-arm of the machine, the section being taken in a plane containing the axes or rotation of the cross-shafts journaled in said bracketconstrained arm. Fig. 4 is an enlarged rear side elevation, with the cross-shafts in section, of the needlebar frame vibrating mechanism. Fig. 5 is a front elevation of a portion of the bracket-arm of the machine. Fig. 6 illustrates, diagrammatically, the path of needle-vibration derived by compounding the simple harmonic motions imparted to the connections employed for vibrating the needle laterally.

The sewing machine containing the present improvement is in general constructed substantially as fully disclosed in the U. S. patent to C. F. Gray, No. 1,020,089, March 12, 1912. The frame of the sewing machine comprises a bedplate I, supporting at one end thereof a standard 2 of a hollow bracket-arm 3 which overhangs the bed-plate l and terminates at its free end in a head 4.

Rotatably journaled in the bracket-arm 3 to extend lengthwise thereof is a horizontally disposed main actuating shaft 5, carrying at one end a combined belt-pulley and balance-wheel 6. At its opposite end, the shaft 5 carries a counterbalanced crank-disk I operatively connectedby a link 8 to impart endwise reciprocatory movements to a vertically disposed needle-bar 9.

The needle-bar 9, which carries at its lower end an eye-pointed needle 10, is journaled for endwise reciprocation in a swinging needle-bar guide or frame l I hung at its upper end upon a fulcrum-pin l2 supported by the bracket-arm head 4 and lengthwise extending transversely of the main-shaft 5. At its lower end, the swinging frame H is provided with an arcuate slot I3 to receive a guide-stud M which confines the frame to swinging movements in a single plane.

Complemental to the needle I0 in the formation of lock stitches is a loop-taker l5 of the horizontal-axis rotary hook type and having its axis of rotation substantially parallel to the fulcrum axis of the swinging frame I 1, whereby the loop-taker rotates in a plane substantially parallel to the plane of vibration of the needle Ill. The loop-taker I5 is carried by a horizontally disposed shaft l6 lengthwise extending transversely of the bed-plate l and suitably journaled for rotation in a bearing-lug l'l depending from the'bed-plate. The loop-taker shaft l6 carries a bevel-gear l8 driven by a similar gear l9 secured upon one end of a loop-taker actuating shaft 20 extending horizontally lengthwise of the bed-plate l and rotatably disposed in a tubular feed-lift rock-shaft 2| journaled in suitable bearings at the under side of the bed-plate. At its other end, the loop-taker actuating shaft 26 carries a pulley 22 connected by a clip-belt 23 to a pulley 24 carried by the mainor armshaft 5. The pulleys 22 and 24 are proportioned so that the loop-taker actuating or bed-shaft 20 performs two rotations for each rotation of the arm-shaft 5. As the loop-taker l rotates in a plane substantially parallel to the plane of Vibration of the needle-bar frame H, the looptaker is adapted to accommodate a limited am plitude of vibration of the needle H! in the absence of compensatory movements of the looptaker.

The present sewing machine has the usual work-feeding mechanism comprising a feed-do 25 operating through a suitably slotted throatplate 26 supported by the bed-plate the feeddog being opposed by the usual spring-depressed presser-foot 21. The feed-dog 25 is carried by a feed-bar 28 operatively connected to a feedrocker 29 of a feed-advance rock-shaft 30. The rock-shaft 36 is journaled in suitable bearing lugs depending from the bed-plate and is provided with a crank-arm 3| pivotally connected to the lower end of a pitman 32. The pitman 32 extends upwardly into the arm-standard 2 and, at its upper end, has a strap embracing a feed-advance eccentric 33 carried by the arm-shaft 5; the eccentric 33 being suitably adjustable as to eccentricity.

In order to impart rising andfalling movements to the feed-dog 25, the feed-bar 28 is operatively connected to a crank-arm 34 of the feed-lift rock-shaft 2|. Suitably secured to the feed-lift rock-shaft 2| is a crank-arm 35 pivotally connected to the lower end of a pitman 36. The pitman 36 extends upwardly into the arm-standard 2 and, at its upper end, is provided with a strap embracing a feed-lift eccentric 31 carried by the arm-shaft 5. Obviously, any other suitable feeding mechanism may be employed and, in fact, the feeding mechanism may be omitted from the machine.

The present invention relates more particularly to mechanism for laterally vibrating one of the complemental stitch-forming elements. To this end, the rotary arm-shaft 5 of the machine is. provided with a gear 38 in driving mesh with a gear 39 relatively proportioned to rotate at onehalf the speed of rotation of the gear 38. The driven gear 39 is secured, by a screw 4|), upon a horizontally disposed cross-shaft 4| for rotation therewith. The cross-shaft 4| extends lengthwise substantially at right angles to the armshaft 5 and the rearward end of the cross-shaft 4| is rotatably journaled in a suitably apertured bearing-boss 42 formed upon the rear wall of the bracket-arm 3. At its forward end, the crossshaft 4| is journaled in a horizontally apertured boss 43 of a cover-plate 44 which is removably secured by screws 45 upon the front side of the bracket-arm 3 to close an opening 46 in the front wall of the bracket-arm.

A secondary cross-shaft 4! is disposed below and in parallelism with the primary cross-shaft 4|; the cross-shaft 4! being likewise rotatably journaled in a horizontally apertured bearingboss 48, formed upon the rear wall of the bracket-arm 3, and in another suitably apertured bearing-boss 49 of the cover-plate 44. The primary cross-shaft 4| carries a driving spur-gear 50 for rotation therewith, which spur-gear 56 is in mesh with a pinion 5| secured upon the secondary cross-shaft 41. The secondary cross-shaft 41 therefore rotates in a direction opposite to that of the primary cross-shaft 4 I. The ratio of the spur-gear 50 and pinion 5| is such that the secondary cross-shaft 41 is rotated thrice for each rotation of the primary cross-shaft 4|, i. e., the secondary cross-shaft 4'| performs one and one-half rotations for each rotation of the armshaft 5. It will therefore be understood that the angular velocity of the cross-shaft 4! is divisible by that of the cross-shaft 4|.

Secured for rotation at uniform angular velocities with the cross-shafts 4| and 41, respectively, are primary and secondary actuating elements or eccentrics 52 and 53, which eccentrics are individually adjustable as to eccentricity. The supporting and adjusting means of the two eccentrics 52 and 53 is substantially the same; said eccentrics structurally corresponding with the needle-vibrating eccentric disclosed in the Gray Patent No. 1,020,089 hereinbefore mentioned. The description of one of the eccentrics 52 and 53 therefore applies equally to the other.

In general, a driver-disk 54 has its hub secured by a screw 55 upon the cross-shaft for rctation therewith. Pivotally secured to a side face of the driver-disk 54, by a screw 56, is an eccentric-carrying frame 51 provided with an arcuate slot 58 for a frame-confining screw 59. The screw 59 is threaded into the driver-disk 54 to permit of limited swinging adjustment of the frame 51 about the pivot-screw 56. The eccentric 52, or 53, extends from the side of the frame 5! opposite the driver-disk 54; the eccentric having a cylindrical periphery and, preferably, an eccentric shaft-clearance aperture 60.

The eccentric-carrying frame 51 is provided with radially opposed apertures 6| and 62 lengthwise extending transversely of the fulcrum-axis 56 of the frame 51. Endwise slidable in the frame-aperture 6| is a plunger 63 yieldingly pressed into engagement with the respective cross-shaft 4| or 47 by a spring 64 compressed by a screw 65 threaded into the frame-aperture 6|. The spring 64 biases the eccentric-carrying frame 57 to swing about the fulcrum-axis 56 thereof to an extent limited by a screw 65 threaded into the frame-aperture 52. The screw 66 passes through a suitable clearance opening in the cross-shaft 4|, or 47, and the inner end of said screw 66 is adapted to engage an adjusting screw 67 threaded into an axial bore 68 of the cross-shaft. The adjusting screw 6'! has an inner tapered end 61, so that by endwise adjustment of the screw Bl, the eccentricity of the eccentric 52, or 53, may be minutely changed. At its outer end, the adjusting-screw 61 has a peripherally knurled head 66 provided with an annular flange 10 embracing the boss 43, or 49, of the cover-plate 44. The adjusting-screw 6! is preferably yieldingly retained in set position by a suitable frictionspring II. The described arrangement provides for individual and minute adjustment of the actuating eccentrics 52 and 53 from zero to maximum.

Embracing the actuating eccentric 52 is a split strap 12 of a follower in the form of a pitman 13, of which the free end is connected by a pivotscrew 74 to a link 75 lengthwise extending transversely of the pitman 73. The link 15 is provided with a plurality of apertures 16 to receive, selectively, a pivot-screw TI joining the link 75 to a connection-bar 18; said connection-bar being provided with corresponding apertures. The connection-bar 18 has one end thereof attached by a pivot-screw 19 to the lower end of the needlebar frame I i, whereby endwise movements of the connection-bar 18 are converted into swinging movements of the needle-bar frame. The eccentric 52 is therefore connected to'the needle-bar frame II by an endwise extensible multiple-section connection-element or pitman including the follower-section I3 and the section 18; said sections 1'3 and 13 being connected by the link 1'5 to permit of relative endwise movements of the sections.

The pitman 13 is also connected by a pivotscrew 86 to another link 8| disposed substantially parallel to the link 15 and likewise connected, by a pivot-screw 82, to the connection-bar 18, thereby providing a four-bar linkage connection between the pitman 13 and the connection-bar 18. The link 8| and the connection-bar 78 are provided with a plurality of apertures 83, selectively to receive the pivot-screw 82 and corresponding in spacing to the apertures 16 of the link 15. The link 8| comprises one arm of a lever 8|, 84, having its other arm 84 connected by a pivot-screw 85 to the free end of a pitman 85. The pitman 86 has a split strap 81 embracing the eccentric 53.

The primary and secondary actuating elements, comprising the two eccentrics 52 and 53, are therefore connected by means of the pitmans 13, 85 and the described four-bar linkage or motioncompounding mechanism to a common actuated element comprising the needle-bar frame connection-bar 18. By rotating the eccentrics 52 and 53 at diiferent frequencies, the endwise movements imparted to the pitmans i3 and 86 are at times unidirectional and at other times oppositely directed. The four-bar linkage connection between the pitmans i3, 85 and the connection-bar 18 therefore results, at times, in additively transmitting the endwise movements of the pitmans T3, 86 to the connection-bar I3 and, at other times, in reducing or substantially nullifying the motiontransmitting action of said pitmans. In the present machine, the timing and eccentricities of the eccentrics 52 and 53, and the proportions of the connection-elements actuated thereby are such that lateral movements are in the main imparted to the needle while out of the work.

The compounding of the efiective motions derived from the eccentrics 52 and 53, andthe consequent reduction of vibration of the needle while in the work are graphically illustrated in Fig. 6 of the drawings. The simple harmonic motion derived by its follower from the primary eccentric 52 is represented by the sine curve A; the line Z-Z representing the zero or central position of the needle medianly of its width of throw. The simple harmonic motion derived by its follower from the secondary eccentric 53 is represented by the sine curve B. The motion-compounding connections described have the effect of superimposing the sine curves A and B, thereby forming the composite curve C which represents the lateral movements of the needle in the present machine.

. The needle-reciprocation is timed so that the needle enters the Work at substantially the points D and leaves the work at substantially the points E of the composite curved line C. It will be particularly noted, from the shape of the line C, that the needle has no substantial lateral movement at the time that the needle enters and leaves the work. The reentrant portion of the curve C between the points D and E thereof shows that, while in the work, the needle has a slight compensating or return lateral movement in each of the oppositely directed main lateral movements of the needle. The compensating movement referred to attains its maximum slightly before the rising needle ID, reaches its position F in which the needle-thread loop presented by the needle is seized by the loop-taker 15.

When, as in the present machine, the looptaker rotates in a plane parallel to the plane of needle vibration and is confined to rotate about a fixed axis, without being accelerated or retarded, the loop-taker can accommodate a limited amplitude of vibration of the needle, as is well understood in the art. The described compensating movements imparted to the needle l8 provide for increasing the lateral movements of the needle while out of the work, inasmuch as the needle may descend outside of the loop-seizing range of the loop-taker and thereafter move back into range before reaching loop-presenting position. As this compensating movement occurs at each extreme of lateral movement of the needle, the width of the zigzag stitches capable of being formed by employment of a given size of looptaker may be substantially increased.

While the present improvement has been devised, prirnarily, to minimize vibration of the needle while in the work and to provide for increasing the width of the stitches produced by a high speed zigzagsewing machine, it will be apparent that the needle-vibration may be varied by changing the phase relationship of the primary and secondary actuating eccentrics,or by relatively changing the frequencies of rotation of the eccentrics, or by relative adjustments of the eccentricities of said eccentrics, or by changing the leverage connections between the eccentrics and the common actuated element. The present improvement thus provides convenient means for readily adapting the machine for producing various kinds of ornamental stitching effects.

Having thus set forth the nature of the invention what I claim herein is:

1. In a sewing machine, the combination with complemental stitch-forming members including an endwise reciprocatory needle and a loop-taker, of means for imparting bodily lateral movements to one of said members, said means comprising a plurality of rotary actuating elements each having a uniform angular Velocity of rotation, means for rotating said actuating elements at different frequencies, and interconnected motion-compounding connections with the respective rotary actuating elements for transmitting lateral movements to said one of said members.

2. In a sewing machine, the combination with complemental stitch-forming members including an endwise reciprocatory needle and a loop-taker,

of means for imparting bodily lateral movements to one of said members, said means comprising a pair of rotary actuating elements each having a uniform angular velocity of rotation, means for rotating said actuating elements in opposite directions, and interconnected motion-compounding connections between said bodily movable member and the respective rotary actuating elements.

3. Stitch-forming mechanism for sewing machines, including an endwise reciprocatory and laterally vibratory needle, a plurality of rotary actuating eccentrics having different frequencies and uniform angular velocities of rotation, pitmans having straps embracing the respective rotary actuating eccentrics, and motion-compounding connections with said pitmans for transmitting lateral vibratory movements to said needle.

4. In a sewing machine, an endwise reciprooae tory and laterally vibratory needle, means for reciprocating said needle, an endwise extensible of connected to transmit lateral vibratory movements to said needle, a primary rotary actuating member operatively connected to another section V of said pitman, a secondary rotary actuating member, and connections with said secondary rotary actuating member for transmitting relative endwise movements to the pitman sections, thereby automatically modifying the effective action of said primary rotary actutaing member.

5. In a sewing machine, an endwise reciprocatory and laterally vibratory needle, means for reciprocating said needle, and endwise extensible multiple-section connection-element having one section thereof connected to convert endwise movements thereof into lateral vibratory movements of said needle, means for maintaining the sections of said connection-element in parallel relation, and actuating mechanism for transmitting endwise movements to the first named section of the connection-element, said actuating mechanism including motion-compounding means for imparting relative endwise movements to the sections of said connection-element.

6. Stitch-forming mechanism for sewing machines, including an endwise reciprocatory and laterally vibratory needle, a plurality of rotary actuating elements having uniform angular velocities of rotation, means for rotating said actuating elements at different frequencies, and interconnected connection-elements including a four-bar linkage for transmitting lateral vibratory movements to said needle from said rotary actuating elements.

'7. Stitch-forming mechanism for sewing machines, including an endwise reciprocatory and laterally vibratory needle, a plurality of rotary actuating elements each havin a uniform angular velocity of rotation, means for rotating said actuating elements at different frequencies, pitmans having straps embracing the respective rotary actuating elements, and a four-bar linkage connecting said itmans and connected to transmit lateral vibratory movements to said needle.

8. In a sewing machine, an endwise reciprocatory needle-bar, a laterally vibratory guide for said needle-bar, a rotary shaft having a uniform angular velocity of rotation and connected to reciprocate said needle-bar, a primary needle-bar vibrating eccentric rotating with said rotary shaft in one-to-two timed relation, a secondary needlebar vibrating eccentric rotating in timed relation with said rotary shaft at a uniform angular velocity different from the angular velocity of rotation of said primary eccentric, and followermeans connected to compound the motions produced by said eccentrics and to transmit the resultant motion to said laterally vibratory needlebar guide.

9. In a sewing machine, an endwise reciprocatory and laterally vibratory needle, a rotary shaft connected to impart endwise reciprocatory movements to said needle, a primary actuating element having a uniform angular velocity of rotation at one-half the speed of rotation of said shaft, a secondary rotary actuating element having a uniform angular velocity of rotation greater than that of said primary actuating element, the angular velocity of said secondary actuating element being divisible by the angular velocity of said primary actuating element, and follower connections with said actuating elements for compounding the motions produced thereby and for transmitting the resultant motion to laterally vibrate said needle.

10. In a sewing machine, an endwise reciprocatory needle-bar, a laterally vibratory guide for said needle-bar, a rotary shaft having a uniform angular velocity of rotation and connected to reciprocate said needle-bar, a primary needlebar vibrating eccentric rotating once for two rotations of said shaft, a secondary needle-bar vibrating eccentric rotating thrice for each rotation of said primary eccentric, and followermeans connected to compound the motions produced by said eccentrics and to transmit the resultant motion to said laterally vibratory needlebar guide.

11. In a sewing machine, an endwise reciprocatory needle-bar, a laterally vibratory guide for said needle-bar, a rotary shaft connected to impart endwise reciprocatory movements to said needle-bar, a primary needle-bar vibrating eccentric rotating with said rotary shaft in oneto-two timed relation, a secondary needle-bar vibrating eccentric rotating in timed relation with said rotary shaft at a speed different from the speed of said primary eccentric, and follower-means including a parallelogram linkage to compound the motions produced by said eccentrics and to transmit the resultant motion to said laterally vibratory needle-bar guide.

12. In a sewing machine, an endwise reciprocatory and laterally vibratory needle, means for reciprocating said needle, a primary rotary actuating element having a uniform angular velocity of rotation and performing a fractional portion of one complete rotation for each complete reciprocation of said needle, a secondary rotary actuating element having a uniform angular velocity of rotation with a frequency different from that of said primary actuating element, follower-devices actuated by the respective rotary actuating elements, and motion-compounding connections with said follower-devices for transmitting lateral vibratory movements to said needle.

13. In a sewing machine, an endwise reciprocatory and laterally vibratory needle, means for reciprocating said needle, a primary rotary actuating element having a uniform angular velocity of rotation and performing a fractional portion of one complete rotation for each complete reciprocation of said needle, a secondary rotary actuating element having a uniform angular velocity of rotation, means for rotating said actuating elements in opposite directions, follower-devices actuated by the respective rotary actuating elements, and motion-compounding connections with said follower-devices for transmitting lateral vibratory movements to said needle.

14. In a sewing machine, an endwise reciprocatory and laterally vibratory needle, means for reciprocating said needle, an endwise extensible multiple-section connection-element having one section thereof connected to convert endwise movements thereof into lateral vibratory movements of said needle, parallel links pivotally connecting the sections of said connection-element, and actuating mechanism connected to impart endwise movements to the respective sections of said connection-element, thereby to transmit vibratory movements to said needle.

15. In a sewing machine, an endwise reciprocatory and laterally vibratory needle, means for reciprocating said needle, an endwise extensible two-section pitman having one section thereof connected to transmit lateral vibratory movements to said needle, parallel links pivotally connecting the sections of said pitman, a primary rotary actuating element operatively connected to impart endwise movements to the other section of said pitman, a secondary rotary actuating element, and connections with said secondary rotary actuating element for transmitting relative endwise movements to the sections of said pitman.

16. In a sewing machine, a vibratory frame, a needle-bar journaled in said frame for endwise reciprocation, means for reciprocating said needle-bar, a primary rotary actuating eccentric, a pitman having a strap embracing said eccentric, a connection-bar pivotally connected to said vibratory frame, a lever pivotally connected to said pitman and connection-bar, a secondary rotary actuating eccentric, and means actuated by said eccentric for rocking said lever.

1'7. In a sewing machine, a vibratory frame, a needle-bar journaled in said frame for endwise reciprocation, means for reciprocating said needle-bar, a primary rotary actuating eccentric, a pitman having a strap embracing said eccentric, a connection-bar connected to said pitman for endwise movement relative thereto and pivotally connected to said vibratory frame, a secondary rotary actuating eccentric, a pitman having a strap embracing said secondary rotary actuating eccentric a lever operatively connected to the secondary eccentric pitman, and means pivotally connecting said lever to said connection-bar and first named pitman.

18. In a sewing machine having an endwise reciprocatory and laterally vibratory needle, a plurality of actuated elements, means for imparting simple harmonic motions of different frequencies to said elements, and motion-compounding means actuated by said elements and connected to laterally vibrate said needle.

19. In a zigzag-stitch sewing machine, the combination with a vibratory needle-bar guideframe, a needle-bar journaled in said frame for endwise reciprocation, a needle carried by said needle-bar, means for reciprocating said needlebar, a loop-taker'cornplemental to said needle in the formation of stitches, and means for actuating said loop-taker, of mechanism for vibrating said needle-bar guide-frame in timed relation to the movements of reciprocation of said needle, said mechanism embodying means for holding said frame substantially stationary at its opposite extremes of lateral movement while the needle is entering the Work and to move said needle laterally while in the work away from its extreme positions of lateral movement preparatory to presenting the needlethread loop for seizure by said loop-taker.

20. In a zigzag-stitch sewing machine, the combination with a vibratory needle-bar guideframe, a needle-bar journaled in said frame for endwise reciprocation, a needle carried by said needle-bar, means for reciprocating said needlebar, a loop-taker complemental to said needle in the formation of stitches, and means for actuating said loop-taker, of mechanism for vibrating said needle-bar guide-frame in timed relation to the movements of reciprocation of said needle, said mechanism embodying means for holding said frame substantially stationary at its opposite extremes of lateral movement while the needle is entering and leaving the work, and to move said needle laterally while in the work away from its extreme positions of lateral movement.

21. In a zigzag stitch sewing machine, the combination with a vibratory needle-bar guideframe, a needle-bar journaled in said frame for endwise reciprocation, a needle carried by said needle-bar, means for reciprocating said needlebar, a rotary loop-taker having a needle-thread loop seizing beak rotating in a plane substantially parallel to the plane of vibration of said needle, and means for rotating said loop-taker, of needle-bar frame vibrating mechanism including means for holding said frame substantially stationary at its opposite extremes of lateral movement while the needle is entering and leaving the work, and for moving said needle laterally while in the work away from its extreme positions of lateral movement preparatory to presenting the needle-thread loop for seizure by said loop-taker.

22. In a zigzag stitch sewing machine, the

combination with a vibratory needle-bar guideframe, a needle-bar journaled in said frame for endwise reciprocation, a needle carried by said needle-bar, means for reciprocating said needlebar, a rotary loop-taker having a needle-thread loop seizing beak rotating in a plane substantially parallel to the plane of vibration of said needle, and means for rotating said loop-taker, of actuating mechanism for vibrating said frame laterally from one extreme to the other while the needle is out of the work, said actuating mechanism including means for maintaining said frame substantially stationary while the needle is entering and leaving the work, and for imparting reversely directed lateral movements to said needle while in the work.

23. In a sewing machine, the combination with an endwise reciprocatory and laterally vibratory needle, means for reciprocating said needle, a loop-taker rotating in a plane substantially parallel to the path of lateral vibratibn of said needle, said loop-taker including a needlethread loop seizing beak having a limited range of cooperation with said needle in laterally spaced positions of the needle, of mechanism for vibrating said needle to enter the work in paths spaced more widely than the limited range of cooperation of said needle and loop-taker, said mechanism including means for laterally moving said needle while in the work into the effective range of action of said loop-taker.

24. In a sewing machine, the combination with an endwise reciprocatory and laterally vibratory needle, means for reciprocating said needle, a rotary loop-taker including a loopseizing beak rotating in a plane substantially parallel to the field of lateral vibration of said needle, said loop-seizing beak of the loop-taker having a limited range of needle-thread loopseizing positions in laterally spaced positions of said needle, and means for rotating said looptaker, of mechanism for laterally vibrating said needle to enter the work in paths outside of said range and at the opposite extremes of lateral movement of the needle, said mechanism including means for moving said needle laterally while in the work away from said opposite extreme positions and into the range of effective action of said, loop-taker beak.

ARTHUR N. HALE.

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