US2400602A - Sewing machine - Google Patents

Description

C. F. RUBEL SEWING MACHINE May 21, 1946.

Filed Dec. 26, 1942 4 Sheets-Sheet l HI I V ATTORNEY Ma 21, 1946. c. F. RUBEL 2,400,602

SEWING MACHINE Filed Dec. 26, 1942 4 Sheets-Sheet 2 IN VEN TOR CHARLES F. RUBEL A TTORNE 0 May 21, 1946. c F RUBEL 2,406,602

' SEWING MACHINE Filed Dec. 26, 1942 4 Sheets-Sheet 3 INVENTOR CHARLES I". RUBEL A ATTOR Y INVENTOR C. F. RUBEL SEWING MACHINE May 21, 1946.

' Filed Dec. 26, 1942 4 Sheets-Sheet 4 CHARLES F. RUBEL ATTORN Patented May 21, 1946 SEWING MACHINE Charles F. Rube], Chicago, 111., assignor to Union Special Machine Company, Chicago, 111., a corporation of Illinois Application December 26, 1942, Serial No. 470,131 26 Claims. (01. 112-248) This invention relates to an improved takeup mechanism for sewing machines and more particularly to a take-up of the rotary type applied to a, lockstitch machine for the control of the needle thread thereof.

A primary object of the invention has been to provide a simple and inexpensive construction for the purpose indicated, with few parts and capable of providing the correct'take-up action at all points in a cycle of operation of the machine.

. Toward this end the machine is provided-with the needle thread from the source of supply to the needle and will thereby facilitate threading operations and reduce to a minimum the danger of thread tangling and breakage. Toward this end the axis of the rotary take-up member is located forwardly of the needle actuating shaft and a thread tensioning device is located at substantially the same elevation as the point of first engagement of the thread by the take-up means and is near and horizontally in line with certain thread guiding and retaining means. Improved control means for the thread tensioning device is also provided.

A further object of the invention has been to provide simple and efiective means for preventing the continuous winding of the needle thread about a part of the take-up means, in the event of breakage of the thread. This is accomplished by the particular construction of a thread engaging element, forming part of the take-up means, and by the provision, relation thereto, of a simple thread positioning finger which is efiective to sever the thread whenever the latter tends to wind upon said element. This element, moreover, is the only part of the take-up to which the thread is likely to attach itself. In this way any substantial wastage of thread, or loss of time in rethreading, after the thread has become broken, is avoided.

Other obJects,'-features andadvantages of the invention will appear from a detailed description of an illustrative form of the same which will in appropriate now be given in conjunction with the accompanying drawings, in which:

Fig. I is a view, largely in vertical section but partly in side elevation, disclosing a lockstitch machine embodying the invention, only a portion of the improved take-up mechanism, however, being shown;

Fig. II is an end elevation of the machine;

Fig. III is a vertical section through the needle head of the machine, taken along the line III--III of Fig. I, a portion of the take-up means to the left of said section being-indicated in dot-and-dash lines;

Fig. IV is a face view of the rotary take-up member;

Fig. V is a detail view showing a threadengaging element forming part of the take-up member, said view being partly in plan and partly in section along the line VV of Fig. IV;

Fig. VI is a sectional view through the takeup member on its supporting shaft, taken along the line VI--VI of Fig. IV;

Fig. VII is a view, in front elevation, showing the needle head and the rotary take-up means;

Fig. VIII is a horizontal sectional Iview along the line VIII-VIII of Fig. VII;

Fig. I is a detail view, in elevation, showing the thread positioning and severing means, and

Fig, X is a vertical section along the line X-X of Fig. VII, showing a detail of the threadtension controlling means.

The invention has been illustrated in connection with a lockstitch sewing machine of the type shown and described in the Christensen and Rubel Patent No. 2,113,572, granted April 12,

1938. This machine comprises a main, frame having a base portion I0, providing a work supporting surface, and a vertical standard II from the upper end'of which extends a substantially horizontal, overhanging arm l2. Power is supplied to the machine through a combined hand wheel and pulley 13 secured to the outer end of a shaft l4 -mounted, at one end, in a bearing [5 in a wall of the vertical standard II and, at its other end, in a bearing [6 carried by the over hanging arm. Shaft l4 extends substantially the full length of the overhanging arm into a needle head I! at the free end of the arm. By means of a crank l8, carried by the shaft I4 at the needle head, power is transmitted through a pitman ill to a needle bar 20 adapted for vertical reciprocation in suitable bearings. At its lower end the needle bar is provided with a threadcarrying needle 2 I.

Power is also transmitted from the shaft l4 to various operating means within the base of the machine. For this purpose a, gear 22 secured to the shaft within the upper end of the standard meshes with an idler gear 23 which in turn meshes shaft 25. Accordingly, the rotary component of the hook will be given two revolutions for each reciprocation of the needle 2| in the formation of stitches. Also driven by the shaft 25, by connections not fully disclosed, but similar to those provided in said Christensen and Rubel patent, is a four-motion feed dog 38 mounted on a feed bar 34. The latter is pivotally connected with a feed rocker arm 32 adapted to be oscillated by ated by the shaft 25, are provided for lifting and lowering the feed dog in properly timed relation. For further details as to any of the foregoing construction, reference may be had to said Christensen and Rubel patent.

Cooperating with the feed dog is a presser foot 33, carried by a vertically disposed presser bar 34 the shaft to produce the feeding and return movements of thefeed dog. Other means, operwhich is 'yieldingly urgeddownwardly by a spring 35 acting against a block 36 secured to the presser bar. Lifting of the presser bar may be accomplished in any suitable manner to enable the introduction and removal of work. Means for this purpose may be controlled manually or by foot treadle operation, or both. Manual raising of the presser bar may, for example, be accomplished by a lever 31 having a cam portion cooperating with an arm 38 carried by a sleeve 39 slidable vertically on the presser bar. The initial movement of the arm and sleeve is idle but when the arm engages the block 36, it will lift the presser bar against the action of the spring 35. When raised suiliciently the presser bar and lever 31 will be retained, with the presser foot inactive, due to the form of the cam portion of the lever. Extending laterally from the arm 3815 another arm'40 (Fig. I) having a downwardly extending portion which carries a cam projection 4|. This cam projection is adapted to engage the inner end of aslidable pin 42 (Fig. X) carried by a sleeve 43 extending through the forward wall of the needle head. A conical shoulder 44 adjacent the other end of the pin 42 cooperates with the lower rounded end of a pin 45 disposed vertically in an upward extension 46 of the sleeve 43, At its upper end the pin is provided with a conical surface 41 adapted to be fo'rced upwardly between a pair of thread-tensioning discs 48 to cam the latter apart. A spring 49 normally urges the outer disc 48 against the inner disc. in a known manner. It will thus be seen that as the'presser bar is raised, the cam projection 4|, acting throughthe pins 42 and 45, will separate the discs 48 slightly and release the tension on the thread which passes between these discs, thereby facilitating removal of the work and cutting of the thread.

Turning now to the needle thread take-up mechanism, there is secured to the shaft l4, within the needle head, a gear 50 which meshes with a gear 5| secured to a take-up shaft 52 journaled in a bushing 53 carried by a bracket or block 54 secured to the under surface of the top of the needle head. The construction is such that for each revolution of the shaft l4 there will be one revolution of the shaft 52. The outer end of the latter is provided with an enlarged portion 55 which is'preferably integral with the shaft and has a flange 56 forming a disc-like member at the extreme end of .the shaft. To the disc-like member 55 is secured a rotary take-up member 51, the latter being attached in any suitable way, as

by screws 58. .Member 51 is of fiat, plate-like- -construction and has its outer edge in the form of a smooth cam surface. The member is so shaped as to constitute a two-lobed cam, with a lobe 59 at the left end (Fig. IV) and a, lobe 60 at the right end. To reduce the weight of the member as much as possible, it is cut out to a substantial extent and may suitably be provided with two relatively large openings 8| and 62. Between the latter, and at one side of the axis of the take-up member, there is mounted directly on this member a thread engaging element 83, which may be attached to member 51 by means of rivet portions 64 at the base of the element, A slot 65, defined by walls-66 and 61 of arcuate form' (as best shown in Figs. II, IV, and IX), having their center of curvature at the axis of the shaft 52, is provided completely across the outer end of the element 63. This slot is quite deep and may suitably extend about two-thirds of the distance from the outer end of the element toward the member 51. The peripheral surface 'of element 63 is oval in cross-section and is of reduced circumference intermediate its ends. It tapers inwardly from the two ends of the element and thus provides a concavity or depression having its root or bottom 68 in a central plane into which the'thread will naturally fall as it is picked up by the element.

The take-up member is largely enclosed by a hood, one side of which is formed by a plate 69 secured to the end face of the needle'head by screws 18. Anarcuate band ll, extending over an arc of somewhat more than 180, surrounds the upper and rearward portion of the take-up member. It may be secured in any suitable way to the plate 69. Forming the outer face of the hood is a plate 12 secured by screws 13 to lugs 14 projecting inwardly from the member 1|. The lower front portion'of "the hoodis-largely closed by a plate 15 having an over-turned ear 15, at one side, secured by a screw 11, or the like, to the inner face of the plate 69. Plate 15 is provided with a long slot 18 through which the lobes 59 and 60 of the take-up member are adapted to project as the latter is rotated, Theslot extends substantially thefull length of the'pla'te 15, including not only its fiat, lower portion but also an arcuate or curved upper portion 19;" 'To .the outer face plate .12 of the hood a small plate is secured by a screw 8!. The plate 80 has a portion extending below the lower, forward edge of plate 12 and is provided beyond this edge with an in -turned finger or arm 82 which extends parallel with the axis of the take-up shaft, and

The upper portion of the head 83 is formed with an inclined surface 86 which serves to direct the thread, at certain times in a cycle, into proper position on the upper edge of the arm 82 for subsequent correct engagement by the element 83.

The operation of the device will now be briefly described. Thread T taken from any suitable source of supply is delivered to a guide bracket 81 secured to the front of, the needle head and, after traversing a series of eyelets in this guide, is passed between the discs 48 of the threadtensioning device. From the latter the thread is passed over a check wire 88, forming part of the thread-tensioning means, and thence through an opening 89 provided in the plate I along an edge formed by a lug 98, bent outwardly from the plate. The thread is then carried across the plate '55 to an opening 9! through which it is passed inwardly to and partly around the take-up element 63, or the positioning arm 82, or both, depending upon the position of the take-up memher and thence downwardly to a guide 92 secured to the plate 69, then to a guide 93 carried by the needle bar, and finall through the eye of the needle and to and through the work. In its passage between the openings 89 and 9|, the thread is engaged by the periphery of the take-upmember 51. The action of this take-up member, including the element 63 carried thereby, is substantially the same as the combined action of the elements 54 and 60 of the take-up means disclosed in the pending Rubel et a1. application Ser. No. 448,084 filed June 23, 1942. Reference may be had to said prior application for a fuller disclosure of the coaction of the several thread engaging means in producing the desired take-up effect upon the needle thread at all points in a cycle of operation. This coaction is such that at times the cam 59, 60 and the element 63 combine their effects additively and at other times subtractively. However, due to various differences between the present construction and that of the prior application certain distinct advantages are derived from the particular combination and arrangement forming part of the present invention. For example, the location of the take-up shaft 52 forwardly of the vertical plane through the shaft l4, and the location of the thread-tensioning device 48 closel adjacent to the plate and horizontally in line with the thread guiding apertures 89 and 9| thereof, serve to provide a more direct path for the thread from the source of supply to the needle so there is less likelihood of entanglement and less danger of breakage of the thread; That portion of the thread which extends between the take-up element 63 and the stationary guide 92 is swung to substantially equal extents forwardl and rearwardly of the vertical line through the needle. Furthermore, the construction embodying the present invention is simpler, less expensive, easier to thread and less likely to get out of order than prior take-up mechanisms.

In the event of needle-thread breakage, considerable difliculty has heretofore been encountered, due to the tendency of the thread to wrap around one or another of the elements of the rotary take-up. If the thread breakage is not observed promptly, a substantial amount of thread may be wound about the take-up element before the .machine is stopped. This has led to excessive wastage of thread and also a loss of time in removing the wrapped thread and rethreading the machine. These difficultie are overcome by the present construction through the simple coaction of the thread positioning and severing arm 82 and the take-up element 83. It

will be apparent from the nature of the take-up means that in the event of thread breakage only the element 63 is likely to produce the objectionable winding action. Assuming now that the thread has broken in the region of the guide 92 while the take-up means is in the position of Fig. II and the'loose end of the thread, upon the release .of tensior. at this time, becomes wrapped about the element 63 in the plane of reduced diameter, this element will draw a-slight addi tional amount of thread from the source of supply until the element 63 is brought into the position shown in Fig. IX. At this time the portion of the thread which spans the upper end of the slot 65, in wrapping about the element 63, will engage the lower edge of the arm 82, at the apex of the sections 84 and 85, and as the take-up element continues its rotation, this portion of the thread will be severed by the arm 82. The free end of the thread extending through the aperture 9| will then be too short for further winding about the element 83 and it will simply be deflected idly upon each movement of the element around its orbit. It should be observed that no sharp cutting edges are required on the arm 82 or the element 83 and a reasonable clearance may be provided between the arm and the walls of the slot 65, thus facilitating the construction and assembly of the parts. In fact,

it has been found that if the leading edges of the slot 65 are left sharp and only a small clearance is left with respect to the arm 82, there is an objectionable tendency for .the loose end of the broken thread to be drawn into the slot again.

While an illustrative embodiment of the in-'- vention has been disclosed in considerable detail,

it will be understood that various changes may be made in the construction and arrangement of the, several parts without departing from the general principles and scope of the invention. The terms and expressions used herein have been used as terms of description and not of limitation.

What I claim is: 1. Needle thread take-up means for a sewing machine which comprises a rotary take-up memher having a cam edge adapted -to engage the thread, fixed guides at opposite sides of said member arranged to cause the same to impart a takeup action to the thread, and an element carried by said member adapted to engage the thread and impart another take-up action thereto.

2. Needle thread take-up means for a sewing machine which comprises a rotary take-up member having a cam edge adapted to engage the thread and impart a gradual take-up and releasing action thereto, and an element carried by said member adapted to engage the thread and impart another gradual take-up and releasing action thereto, said member and element being arranged to combine their take-up and releasing actions additively in a'portion of a cycle and substractively in another portion of the cycle.

3. Needle thread take-up means for a sewing adapted to engage the thread and impart another gradual take-up and releasing action thereto, said cam edge being so constructed and arranged as to have two take-up actions upon the thread on v each revolution of said member.

4. Needle thread take-up means for a sewing machine which comprises a rotary take-up member having a cam edge adapted to engage the carried by said arm, complementary stitch forming means beneath said work support, a needle operating shaft in said overhanging arm, a rotary take-up shaft disposed above and forwardly of said needle operating shaft and'parallel therewith and connected for rotation with the latter, and needle-threadtake-up means mounted upon said take-up shaft adapted to provide the entire and only take-up actions imparted to said thread.-

6. In a sewing machine having a work support and an overhanging arm, a reciprocatory needle carried by said arm, a needle operating shaft in said overhanging arm, a rotary 100p taker beneath said work support cooperating with thread, fixed guides at opposite sides of said member arranged to cause the same to impart a takesaid member to retain a portion of the thread in cooperative relation therewith, and a thread tensioning device adjacent said guide cooperating with the thread Just in advance thereof.

10. In a machine of the class described a rotary thread take-up member having a thread enga ing element adapted to be carried. bodily around an orbital path and having a take-up action in said path, and a stationary thread severing element in said orbital path, said thread engagin element having a slot 'and said thread severing element having a portion extending into said slot during relative movement of said elements.

11. In a machine of the class described a rotar thread take-up member having a thread enga ing element adapted to be carried bodily around an orbital path and having a take-up action in said path, and stationary thread severing means in said orbital path, said element being slotted to provide radially spaced parts for receiving said severing means therebetween during relative movement thereof.

12. In a, machine of the class described a, rotary thread take-up member having'a thread engagsaid needle in stitch formation, means for rotating said loop taker at twice the angular speed of said needle operating shaft, a rotary take-up shaft disposed above and forwardly of said needle operating shaft and parallel therewith and connected for rotation with the latter, and needlethread take-up means mounted upon said takeup shaft adapted to provide the entire and only take-up actions imparted to said thread.

7. In a sewing machine having a work support and anoverhanging arm, a reciprocatory needle I carried by said arm, complementary stitch forming means beneath said work support, a needle Operating shaft in said overhanging arm, a rotary take-up shaft disposed above and forwardly of said needle operating shaft and parallel therewith and connected for rotation with the latter, and needle-thread take-up means mounted upon said take-up shaft adapted to provide the entire and only take-up actions imparted to said thread, said take-up means being constructed and arranged to swing the thread approaching the needle to substantially the same extent on opposite sides of the path of the needle. I

8. In a sewing machine having a work support and an overhanging arm, a reciprocatory needle carried by said arm, complementary stitch form- 'ing means beneath said work support, a needle operating shaft in said overhanging arm, a rotary take-up shaft disposed above and forwardly of said needle operating shaft and parallel therewith and connected for rotation with the latter. needle-thread take-up means mounted upon said take-up shaft adapted to provide the entire and only take-up actions imparted to said thread, means adjacent said thread take-up means for guiding and retaining the needlethread, and a tensioning device adjacent said guiding means.

ing element adapted to be carried bodily around an orbital path and having a take-up action in said path, and stationary thread severing means a in said orbital path, said element having an arouate slot having its depth in an axial direction' adapted to cooperate with a portion of said severing means during the orbital movement of said element.

13. In a machine of the class described a rotatable shaft, a thread take-up member carried by said shaft, said member having its edge of varying radius from the axis "of said shaft, guide means for directing the thread into cooperation with said edge, a take-up element carried by said member through a circular orbit upon rotation of said member, said element having spaced thread engaging portions, and stationary thread 9. In a sewing machine having a work support and an overhanging arm,: a reciprocatory needle carried by'said arm, complementary stitch forming means beneath said work support, a need e operating shaft in said overhanging arm, a rotary take-up shaft disposed above and forwardly of said needle operating shaft and connected for rotation with the latter, needle-thread take-up means mounted upon said take-up shaft adapted to provide the entire take-up actions for said thread, said take-up means including a member having a camming edge, a guide cooperating with severing means disposed Within the path described by the space between said thread engaging portions.

14. In amachine of the class described a rotatable shaft, a thread take-up member carried by said shaft, a take-up element-carried bodily by i said member through a circular orbit upon rotation of said member, said element having spaced thread engaging portions,'and stationary thread severing means disposed between the paths described by said thread engaging portions, the

spacing of said portions of said element being sufficient only to permit the free passage thereof at opposite sides of said severing means.

15. In a machine of the class described a rotatable shaft, a thread take-up member carried by said shaft, said member having its edge of varying radius from the axis of said shaft, guide means for directing the thread into cooperation with said edge, a take-up element carried by said member through a circular orbit upon rotation of said member, said element having an arcuate groove in its outer face,- and stationary thread severing means arranged to traverse said groove upon each revolution of said member.

16; In a machine of the class described a rotatable shaft, a thread take-up member carried by said shaft, said memberhaving its edge of severing means arranged to traverse said ,groove upon each revolution of said member, the outer surface of said element being so formed as to direct any thread winding about it into a vertical plane intersected by said thread severing means.

17. In a machine of the class described a rotatable shaft, a thread'take-up member carried by said shaft, said member having its edge of varying radius from the axis of said shaft, guide means for directing the thread into cooperation with saidedge, a take-up element carried by said member through a circular orbit upon rotation of said member, said element having an arcuate groove in its outer face, and stationary thread severing means arranged to traverse said groove.

upon each revolution of said member, the outer surface of said element being inclined inwardly from both ends toward an intermediate plane, said plane being intersected by said severing means.

18. In a machine of the class described a rotatable shaft, a thread take-up member carried by said shaft, said member having its edge of varying radius from the axisof said shaft, guide means for directing the thread into cooperation with said edge, a take-up element carried by said a thread-severing element extending transversely of saidplane of rotation of said take-up member and disposed to traverse said slot in the rotation member through a circular orbit upon rotation,

of said member, said element having an arcuate groove in its outer face, and stationary thread severing means arranged to traverse said groove upon each revolution of said member, the outer surface of said element being inclined inwardly from both ends toward an intermediate plane,

said plane being intersected by said severing means, and said severing means having a thread severing edge inclined in opposite directions toward the point of intersection of said means with said plane.

19. In a sewing machine, a thread take-up'device comprising, adjacent thread-engaging members rotatable in a common plane about a common axis, and about which members the thread may abnormally wind, said members being spaced one from the other on a common radius and providing therebetween an arcuate severing-element clearance slot concentric with the paths of rotation of said members, and a thread-severing element extending transversely of said plane and disposed to traverse said slot in the rotation of said members. Y

20. In a sewing machine, a rotary thread takeup device comprising, adjacent threadengaging members rotatable in a common plane about a common axis, and about which members the thread may abnormally wind, said members being spaced one from the other on a common radius and providing there-between an arcuate knife clearance slot concentric with the paths of rotation of said members, and a thread-severing element extending transversely of said plane and disposed to traverse said slot in the rotation of said members, said thread-severing element having a knife-edge at the side thereof flrst approached by the leading end of said slot.

21. In a sewing machine, a rotary thread takeup member having an orbital path of rotation and about which member the thread may abnormally wind circumferentially, said member being provided between the radially outer and inner faces thereof with a slot extending depthwise of said member.

' 22. In a sewing machine, a thread take-up device comprising, a diskrotatable about a fixed axis, a thread-engaging member extending from a side face of said disk eccentrically to said axis, said member being provided in the side face thereof opposite to said disk with a severingelement clearance slot, and a, thread-severing element extending transversely of said side face of the disk and disposed to traverse said slot in the rotation of said member.

23. In a sewing machine, a thread take-up device comprising, a disk rotatable about a fixed axis, a thread-engaging member extending from a side face of said disk eccentrically to said axis, said member being provided in the side face thereof opposite to said disk'with an arcuate severing-element clearance slot having said axis as its center of curvature, and a stationary threadsevering element disposed to traverse said slot in the rotation of said member.

24. In a sewing machine, a rotary thread takeup member having an orbital path of rotation and about which member the thread may abnormally wind circumferentially, said member being provided between the radially outer and inner faces thereof with a slot extending depthwise across the plane of rot tion of said member, means for confining the bread for engagement by said member, and a thread-severing element disposed to traverse said slot in the rotation of said member.

25. I a sewing machine, a thread take-up device comprising, a disk rotatable about a fixed axis, a thread-engaging member extending from a side face of said disk eccentrically to said axis,

,said member being provided in a side face thereof for rotation therewith, said take-up shaft being positioned forwardly of said needle actuating shaft, thread take-up means carried by said takeup shaft, thread guiding means adjacent said take-up means forwardly thereof, thread tensioning means adjacent and horizontally in line with said thread'guiding means, said tensioning means comprising a spring urged disc having its axis disposed at substantially a right angle to said take-up shaft, the construction and arran ement being such that the thread is led in a. substantially straight horizontal line from said tensioning means through said guide means and across the path of said take-up means.

CHARLES F. RUBEL.

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