US1946514A - Trimming attachment - Google Patents

Description

Feb. 13, 1934. J. P. WEIS TRIMMING ATTACHMENT 5 Sheets-Sheet 1 Filed Oct. 51, 1932 INVENTQR. J07; .Ph/ezs Feb. 13, 1934. R as 1,946,514

TRIMMING ATTACHMENT Filed Oct. 31, 1932 5 Sheets-Sheet 2 IN V EN TQR P Wei 5 14%EYS.

Feb. 13, 1934. 4 J. P, 515 1,946,514

TRIMMING ATTACHMENT Filed Oct. 31, 1952 5 Sheets-Sheet 3 INVENT0R.

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Feb. 13, 1934. J, p was TRIMMING ATTACHMENT Filed Oct. 51, 19:52 Sheets-Sheet 5 PINVENYTORJ Jo/m PM/e z 6.

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Patented Feb. 13,- 1934 TRIIVIMING ATTACHMENT John P. Weis, Nyack, N. Y., assignor .to The Metropolitan Sewing Machine Corporation, Nyack, N. Y., a corporation of Delaware Application October 31, 1932. Serial No. 640,490

23 Claims. (Cl. 112-124) This invention relates to sewing machines, more particularly toa trimming attachment therefor which may be applied readily to any of the well-known lock stitch machines in which the stitch is made with a needle and bobbin threads or with two needles and one bobbin thread.

The object of this invention is the provision of an improved feeding and trimming attachment 3. for producing a pinked edge adjacent the seam whereby the stitched article may have its edges pinked to prevent raveling of the threads of the trimmed edge, and which feeding and trimming attachment is so mounted that it can be quickly attached and detached from the machine, or be swung into and out of operative position to permit the machine to be used for plain stitching along the center of a piece of goods.

In the manufacture of dresses and similar articles, it is sometimes required that an operator do the entire work of making a garment, sewing of the pieces together, stitching on the trim, such as lace, binding, piping, cording and other stitching such'as sewing in pleats, tucks or folds frequently required by-the unlimited variations in designs and styles of the respective factories where such machines are used. To meet this requirement, it is essential that the feeding and trimming member be s'hiftable into and out of operative position or be attached and detached from the machine quickly and Without difficulty and, in the present improvement, I have shown.

panying drawings since the. invention is capable two ways by which this may be readily accom plished.

In the drawings accompanying and forming a part of this specification, Fig. 1 is a front e1eva-' tion of a well-known Willcox &- Gibbs machine with this improved auxiliary feeding and trimming attachment applied thereto.

Fig. 2 is a sectional View taken on line 2-2 of Fig. 1, looking in the direction of the arrow, the full lines showing the feeding andtrimming attachment in working position and the dotted lines illustrate it swung out of cutting position.

gether with a seam made with a two-needle lock ;sire to have it understood that the invention is Fig. 3 illustrates two pieces of goods sewn to mer applied thereto, a portion of the arm being broken away to show the eccentric for operating the feed or trimmer from the top shaft. Fig. 6 is a fragmentary sectional'view. of the stitching mechanism of the machine showing the an rotary hook and bobbin case, the feeding or cutting elements adjacent thereto being shown in section clearly to illustrate the mounting and co-operation of the parts of the attachment.

Fig. 7 is a detail view of the eccentric carried by the top shaft of the machine, the-connection operated thereby and a roller clutch for giving step by step movement to the feeding or pinking cutter.

Fig. 8 is a perspective view of the complete feeding and trimming attachment.

Fig. 9 is a sectional detail view of the swing bracket for the top feed and pinking attachment, and. illustrates the manner in which the parts are lubricated, and- Fig. 10 illustrates one form of a resilientTe'ed disk that may beused in place of the cutter when the attachment is used as an auxiliary feed mechanism, the sectional view showing a steel core carrying a rubber surface. w

Similar characters of reference indicate corresponding parts in the several views.

:Before explaining: in detail the present improvement and mode ofoperation thereof, 1 de.-

. not limited to the details of construction and arrangement of parts illustrated in the accomof other embodiments and that the phraseology which I employ is for the purpose of description and not of limitation,

Figs. 1 and 2 ofthe drawings illustrate the mounting of the top feed and trimming attach-'- ment so that it may be swung into and out of operative position.

Figs. 4, 5, 6 and 8 show another form of top feed and trimming attachment that can be readily placed in working position and removed by the operator, to adapt the machine to different kinds of work. v

In the regular base plate- 1 of the machine is mounted for operation the usual four-motion feeding mechanism, generally indicated by 2, and also the hook shaft 3 for operating a hook or shuttle 4 that carries the usual bobbin formak- 5 ing the well-known lock stitch. This part of the stitching mechanism is well known and a detailed description is deemed unnecessary. The control parts are indicated by 5.

The hook shaft 3 is driven by a belt 6, or its no the stitching mechanism, all of which form no part of this invention.

The bottom four motion feeding mechanism is alsooperated from the top shaft '7, and this top shaft is carried in an arm attached to the base I by the vertical trunk 16 in the usual manner. The present day lock stitch machines are capable of operation with a large bobbin by reason of the fact that the hook shaft 3 is usually operated at a ratio of 2 or 3 to one of the top shaft 7, either by belt or gears. Thus, the hook 4 makes two or three revolutions to each reciprocation of the needle and because of this, a short stroke take-up handlinga minimum of thread back 'and-forth through the eye of the needle is used. This feature has proven to be a decided advantage in high speed stitching, but it carries with it the disadvantage that nothing but the hook for co-operating with the needle can be operated from the hookshaft 3 because of this excessive speed. It must be absolutely free in its bearings, with the least possible friction. Otherwise, it will generate heat, the bearings will burn out and the machine quickly go out of commission. 1

The most perfect alignments, fitting and lubrication are required for these high speed hook shafts. Machines that operate at 4000 stitches per minute require that the hook shaft 3 turn in its bearings at the rate of 12000 revolutions per minute. Great difiiculty has been experienced in meeting this requirement, and because of this, the duty on these parts for merely operating the hook 4 is about all the mechanism will stand.

pose of bringing the cutting elements into proper working relation. Mounted on this eccentric is ahanging arm 21 of the trimming attachment, this arm fitting overand being clamped to the eccentric 18 by a cap 22, held in place by a clamp screw 23 and a binding bolt 24. By this means, the trimmer is adjustably supported by the eccentric for swinging movement thereon.

The lower end of the arm 21 is provided with bearings 25 and 26 (see Fig. 1), in which operates a cutter shaft 27 carrying a cutter 28 secured thereto in any suitable way as by means of a clamp screw 29 threaded into the shaft 2'? (see Fig. 6)2 The shaft 27 is provided with a collar 30 clamped thereto by a screw. This collar separates the bearings 25 and 26 and prevents end movement of the cutter shaft in the bearings.- The right-hand end of the shaft 27.has a reduced diameter 32 to which is secured by a screw 34 a member 33 of a roller clutch (see Figs."6 and '7). This clutch is provided with rollers 35 operating on cam surfaces 36.and are maintained inworking position by springs 37. The clutch has a banjo shaped face plate 38 (see Fig. 8), having a stem 39 secured to the cammed surface of the clutch by screws 40. While I have shown a roller clutch, any of the well known clutches capable of step by step motion may be used.

Clamped to the stem 39 is a sliding piece 41 (see Fig. '7), capable of adjustment along the stem 39 for increasing or decreasing the throw or step by step movement of the cutter 28. This sliding member 41 is clamped to the stem by a screw 42 to prevent it shifting during operation of the machine. shoulder screw 43 is the lower end of a pitman connection 44 which is operated by an eccentric 45 secured to the top shaft '7. The pitman connection is provided with a cap 46 forming half of the bearing on the eccentric, and the parts are secured together by screws 47. These screws are accessiblev for adjustment and replacement underneath the arm 15 as shown in Figs. 1 and 5, so that this pitman connection can be removed and replaced without disturbing the shaft 7 or the eccentric 45 on the arm 15 of the machine. The arm 15 is cut away at 48 to provide clearance for the pitman connection.

The hanging arm 21 is shown in dotted lines, Fig. 2, shifted to a non-cutting position. To hold the parts in that position, the clamp screw 24 is tightened and thus securely fastens the parts against fiuther swinging movement. At the bottom portion of the swinging arm adjacent to the bearing 25 is a projecting hub 48 (see Figs. 1 and 2). This hub is bored to receive a locking bolt 49 which has an end 50 threaded into the base 1 of the machine. The top of this locking bolt is also threaded to receive adjusting lock.nuts 51 and wing nut 52. The lock nuts clamp against the top surface of the hub 48 while the shoulder of the threaded portion 50 clamps'against the bed plate of the machine. This locking bolt securely fastens the parts in cutting position and also ties the top arm 15 to the base 1 to prevent deflection of the arm from the base under the cutting pressure of the cutter 28, the pressure for severing ordinary fabrics being over fifty pounds, and when crossing seams of any thickness the pressure is even greater so that, without this binding bolt 49 there would be a tendency forthe top arm 15 to spring upward under this excessive pressure, throwing the needle out of alignment and preventing proper registration with the loop taking hook carried in the base. Therefore, in tying the arm to the base, the'entire strain on these members is taken care of and suflicient rigidity obtained to meet the requirements exactly where the pressure occurs while leaving sufiiicent Attached to this clamp by a space to the right of the needle for clearance of the work so that a fair margin can be trimmed therefrom.

To shift the cutter from the full line position shown in Fig. 2 to the dotted line position, it is only necessary to release the binding bolt 49 by means of its wing nut 52 and shift it to the dotted line position and then tighten the wing nut 24. With the parts in this position a free workspace is provided underneath the arm for handling bulky work and stitching into and away from the edge thereof and the machine can thus be used for'any stitching operations with-out trimming.

To lubricate the cutter shaft 2'7 I provide a lubrication of the shaft 27 (see Fig. 1'). Thus,

ing '75 of the machine base 1.

the trimming attachment is not only shiftable into and out of working position but it can also be readily removed by simply unscrewing the screws 23 and .24, removing the cap 22 and by unscrewing the screws 47 the pitman 44 is also detached. Thus, by this simple means, the entire mechanism may be removed from the machine.

The feeding and trimming attachment may also be clamped to the bed l of the machine as by two threaded bolts 56 (see Fig. 4) having wing or clamping nuts 57 either above or below the base 1. In this form the attachment comprises a bracket 58 (see Figs. 4 and 8) drilled to receivea shaft 59 on which is mounted for swinging movement an arm 60. This arm is provided with two hubs 61 and 62 (see Figs. 8 and 9) supported by the shaft 59. This arm also carries bearings 25 and 26 for the feed and cutter shaft 2'7, the collar 30 and the clutch 33. The attachment bracket 58 has an extending portion 63 projecting under the arm and an overhanging arm 64 threaded to receive an adjusting means 65, in which is located one end 67 of a pressure spring 66 (see Fig. 6), while theibottom end engages at 68 against the bearing 25 to give downward pressure to the cutter 28. I

When the feeding and trimming attachment forms a part of the cloth plate of a sewing machine, it is necessary in orderto convert the machine from an auxiliary feeding or a pinking and seaming machine to a plain stitcher,.to remove the cloth plate and substitute another plate therefor. However, in the present improvement, the auxiliary feeding or trimming attachment shown and described can be applied to any of the machines now in use and can thereafter be converted at the will of the operator for auxiliary feeding or pinking and seaming or plain stitching whenever necessary. In the present improvement, the cutter is driven from the top shaft of the machine, the connection for this drive being also detachable.

To have the trimming attachmentfunction not onlyas a trimmer but as an auxiliary feed I substitute a resilient disk for the cutter for in feeding the work, it is desirable to provide means to coaot with the-cutting knife or resilient disk 28 to .freely rotate therewith with a minimum of friction and this whether the'cutter is acting as a cutter or as a feed as the work passes through the machine. Therefore, I have provided a cylindrical member 69 overlapping a portion of the rotary hook '4 so as not to interfere with the forming of the stitches (see Figs. 1, 2 and 6).

This member takes the pressure of the top feed disk or the cutter at '70 (see Fig. 6), the top surface in contact with the knife or resilient disk being flush with the top surface of the bed plate 1 and the throatplate 71 of the machine so as to form no obstruction for free passage of the work being stitched. This cylindrical member 69 is provided with a stem 72 which has mounted thereon ball bearings 73 and 74 in spaced relation so as to prevent tipping or rocking movement of the cylindrical member under pressure of the cutter 28 and these ball bearings rest in the bear- A spacing collar '16 fits freely on the stem '72 for clamping the ball bearings. The right hand end 77 of the stem is threaded to receive a lock nut 78 to clamp against a similar nut '79 and this provides a means bearing is also a felt washer 81 to prevent grit and foreign substances entering the bearing.

The hook shaft 3 rotates freely in the stem 77 of the cylindrical member and is properly lubricated through the opening 82 which has a felt wick 83to exclude grit from the hearing. The lubricant passes through suitable openings in the spacing collar 76 and the stem 77 which forms the bearing for the shaft 3. 1

To prevent a lateral shifting of the ball bearings and the cylindrical member 69, I provide a clamping collar 84 secured by a screw 85 to hold the right hand ball bearing in exact location. This, together with the spacing collar 76 resting against the two ball bearings, holds the left hand ball bearing in proper working position to limit the end movement of the cylindrical member 69. The arrangement of these parts is such as to fit the standard machine with a minimum of alteration. The only change necessary is to enlarge the present bearing for the hook shaft 3 to accommodate the ball bearing mounting for the cylindrical member 69 and when these parts are arranged in the machine, they do not interfere in any way with the ordinary use thereof as a plain stitcher. After this has been done, the-attachment of-the trimmer parts is a simple matter which can be accomplished by the ordinary operator in a few. minutes.

While I have shown and described the invention as attached to a Willcox 8; Gibbs sewing machine, it is not limited'thereto. The attachments can be applied toany of the well known machines now in use for producing lock stitch seams and, moreover, can also be used in connection with machines making other forms of stitches.

In Fig. 3, I have illustrated the work that the machine is capable of doing. A represents the top piece of fabric; B the bottom piece secured together by stitches C and D. These stitches are made by two needles in tandem relation as shown in Fig. 4, one needle being mounted in advance of the other. The loops of needle threads are entered by the hook 4 and cast around the usual bobbin. The top surface of the work showing the stitches made by the needle threads 0 and D indicates that they are lying in parallel relation side by side. This is due to the fact that the needle threads are round and even though the stitch is made in tandem relation, they slide off one another and lie more or less side by side. The pinking cutter makes the toothed edge E which is useful to prevent raveling of the fabric and, at the same time, produces an ornamental efiect. It will be understood that by substituting a round or plain disc knife in place of the pinking knife 28, a straight out edge would be produced,

the change from one to the other merely requiring the substitution of the one knife for the other.

In the construction of the attachment shown in Figs. 1 and 2,- fixed relation of the members is provided without the use of a spring togive pressure to the ,cutter. Instead, I provide an eccentric adjustment through which the cutter is brought into cutting relation with the cylinder 69, while in the construction of the attachment shown in Figs. 4, 5, 6 and 8 a spring pressure is provided to keep the members in cutting relation. Provision for adjusting the cutter to and from the needle by shifting the cutter shaft 2'? in the bearings enables the width of the seam to be regulated from the stitch line to the pinked edge; the width of the cylinder face 69 against which the cutter 28 has contact being suflicient for all widths of seams required.

In place of the means 56 and 57 for securing the attachment to the base plate 1 of the machine, a clamping means such as 90, illustrated in dotted lines, Fig. 4, maybe used. This form of clamping means facilitates the removal of the attachment without the necessity of tipping the machine back when nuts such as 57 are used.

Experience has shown that this improved trim ming attachment is also useful. as an auxiliary feeding mechanism since the pinking cutter or knife, because of its zig-zag cutting surface acts einciently as a feed for many kinds of work.

For other kinds of work, a resilient disk or cylinder 91 of rubber, cork or similar material that will yield under pressure and conform to the variations in thickness of the work such as that illustrated in Fig. 10 may be used in place of the cutter 28. Thus for certain kinds of work, by this simple change, the attachment is readily converted from a trimming means into a feeding means and forms an auxiliary rotary top and bottom feed, and since both members 28 and 91 have a step by step rolling action synchronized with a movement of the work by the regular four-motion feed, a feeding attachment is provided having advantages for quite a variety of stitching operations, especially as different feeding members such as 91 may be readily substituted for the cutter 28.

By reason of the fact that a rolling action on the work is obtained, there is always a constant grip on the work, no pounding or reciprocating action as with the ordinary feed where it must lift the presser foot each time the work is moved a stitch length. The tension or pressure on a presser foot ranges from eight tofifteen pounds and has a tendency to load up the ordinary machine so that the rolling action of this improved auxiliary feed will have a smooth contact when a resilient feeding member is used in co-operation with the cylinder 69 operating on ball bearings almost-entirely free from friction. Thus the parts form a rolling feed acting in place of a presser foot, this rolling feed in the present improvement being driven from the top shaft.

- The organization of the parts is such that sufficient space for feeding the work to the right of the member 28 is provided, making the improvement practical on many stitching operations.

It is to be understood that, by describing in arrangement, it is not intended to limit the in' vention beyond the terms of the several claims or the requirements of the prior art.

Having thus explained the nature of my said invention and described a way of constructing f n arm and a shaft in said arm. an armsuspended from said top arm for swinging movement-arm tary trimmer carried at the lower end of said and using the same, although without attempting to set forth all of-the forms in which it may be made, or all of the modesof its use, I claim:

1. In a sewing machine having a top arm and a shaft therein, a trimming attachment supported for swinging movement into and out of operative position and. having a rotary cutter, and a pitman connection between said shaft and cutter for rotating it. i J

2. In a sewing machine having a top arm and a shaft therein, a trimming attachment supported for swinging movement on-said top arm in a vertical plane transverse to the top arm into and out of operative position and having a rotary cutter, and means between said shaft and cutter for rotating it. 3. In a sewing machine .having a top arm and a shaflt therein, the combination of a rotary trimmer, and a pitman connection between the top shaft and trimmer for rotating it.

4.v In a sewing machine having a top arm and a shaft therein, a rotary trimmer, a shaft therefor, means for supporting said trimmer shaft, an eccentric carried by the top shaft, and means connecting said eccentric and trimmer shaft for rotating it. 5. In a sewing machine having a base, atop arm and a shaft in said top arm, the combination of a rotary trimmer, means for rotating it, and

means for positioning the trimmer in operative position and comprising an arm connected with the top arm and connected with the base for tying the top arm and base together. I

6. In a sewing machine having a base, a top arm and a shaft in said top arm, the combination of a rotary trimmer, means for rotating it, and means for positioning the trimmer in operative position and comprising an arm connected with the top arm and connected with the base for tying the top arm and base together, said arm supported on the top arm for swinging movement and detachably connected with the base whereby the trimmer may be swung intoand out of its operative position.

7. In a sewing machine having a base, a top arm and a shaft in said top arm, the combina-,

tion of a rotary trimmer, means for rotating it, and means for positioning the trimmer in operative position and comprising an. arm connected with the top arm and connected with the base for tying the top arm and base together, said arm eccentrically supported on the top arm for swinging movement and detachably connected with the base whereby the trimmer may be swung into and out of its operative position.

8. In a sewing machine having a base, a top arm and a shaft in said top arm, the combination of a rotary trimmer, means for rotating it, and means 'for positioning the trimmer inoperative position and comprising an arm connected with the top arm and connected with the base'for tying the top arm and base together, said arm eccentrically supported on the top arm forswinging movement and detachably connected with the base whereby the trimmer may be swung into and out of its operativev position, said eccentric support being adjustable toregulate pressure on the trimmer. detail herein any particular form, structure or i 9. In a sewing" machine having a base, a top arm, and a shaft in said arm, an arm supported on said top arm for swinging movement, a rotary swinging arm, means for rotating the trimmer from the top shaft, and means for exerting pressure on the trimmer.

11. In a sewing machine having abase, a top arm and a shaft in said arm, an arm supported on said top arm for swinging movement, a rotary member carried at the lower end of said swinga ing arm, means for rotating the'member, and means for detachably and rigidly securing the member in position.

12. In a sewing machine having a toparm and a shaft therein, an arm eccentricallys'upported on said top arm for swinging movement, a rotary trimmer carried at the lower end thereof, and means for rotating the trimmer.

13. In a sewing machine having a top arm and a shaft therein, an arm eccentrically supported on said top arm for swinging movement, a rotary trimmer carried at the lower end thereof, and means for rotating the trimmer and including an eccentric carried by the shaft.

14, In a sewing machine having a top arm and a shaft therein, the combination of a rotary trimmer, means for exerting pressure thereon, and a pitman connected with the top shaft and trimmer for rotating the trimmer.

15. In a sewing machine having a top arm and a shaft therein, the combination of a rotary trimmer, means for exerting a pressure thereon, and a pitman eccentrically connected with the top shaft and trimmer for rotating the trimmer.

16. In a sewing machine having a top arm and a shaft therein, the combination of a rotary trimmer, a pitman connected therewith and with the top shaft for rotating the trimmer, a hook-carrying shaft, and a freely rotatable cylinder on said hook-shaft and co-operating with the rotary trimmer.

17. In a sewing machine having a base and a top arm, a hook-carrying shaft carried by the base, a shaft carried by the top arm, a rotary trimmer, a freely rotatable cylinder partially enclosing the shuttle and co-operating with the rotary trimmer, and means operative from the top shaft for rotating said trimmer.

30 18. In a sewing machine having a top arm and a shaft therein, the combination of a rotary trimmer, a pitman connected therewith and with the top shaft for rotating the trimmer, a hook-carrying shaft, a freely rotatable cylinder on said hook shaft and co-operating with the rotary trimmer, and means for supporting the trimmer for swinging movement into and out of its operative position.

19. In a sewing machine having a top arm and a shaft therein, arotary trimmer, a shaft therefor, means for supporting said trimmer shaft, an

eccentric carried by the top shaft, means con necting said eccentric and trimmer shaft for rotating it, and eccentric means carried by the top arm for adjustably and swingingly supporting said trimmer shaft supporting means.

20. In a sewing machine having a base plate, a top arm, and a shaft in said arm, a pair of cooperating rotary members located one above the other adjacent to the needle of the machine, one supported above and the other below the base plate, the lower member being loosely mounted for rotation with the top member, and means operated from the top shaft for rotating the top member.

21. In a sewing machine having a base, a top arm, and a shaft in said arm, a pair of co-operating rotary members located one above the other adjacent to the needle of the machine, the lower member being loosely mounted for rotation with the top member, and means operated from the top shaft for rotating the top member, said top member and its operating means being supported for swinging movement into and out of operative position.

22. An attachment for sewing machines having a base plate and comprising a pair of rotary cooperating members located one above the other adjacent to the needle of the machine, one supported above and the other below the base plate, 1:35 the top member having a resilient formation and the lower member being loosely mounted for ro- 7 tation with the top member, and means for r,otating the top member.

23. In a sewing machine, a trimming attach- 11; ment eccentrically supported for swinging movement in a vertical plane and having a rotary cutter andeccentrically operated means for rotating said cutter.

JOHN P. WEIS.

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