US2801602A - Attachment for blindstitching - Google Patents

Description

1957 v. J. SIGODA ETAL 2,801,602

ATTACHMENT FOR BLINDSTITCHING Filed March 25, 1953 3 Sheets-Sheet 1 INVENTORS V/c TOR a 5 6004 By Amm/mer /aom a firm? 1957 v. J. SIGODA ETAL 2,801,602

v ATTACHMENT FOR BLINDSTITCHING Filed March 23, 1953 S Sheets-Sheet 2 L W m1. Y/A 34 36 31 4 20 )9 4 IN V EN TORS 1957 v. J. SIGOHDA ETAL 2,801,602

ATTACHMENT FOR BLINDSTITCHING Filed March 23, 1955 a Sheets-Sheet s 'siaai-faz" 74 25 .79 a 75 5 INVENTORS w: 70/? LS/cow: Aw (/[RRY 5/600 United States Patent 0 ATTACHMENT FOR BLINDSTITCHING Victor J. Sigoda, Great Neck, and Jerry Sigoda, Bronx, N. Y., assignors to Man-Sew Corp, New York, N. Y., a corporation of New York Application March 23, 1953, Serial No. 344,640

9% Claims. (Cl. 112-440) This invention relates to attachments for sewing machines for applying a folded strip of material, commonly known as piping, either to the raw edge of garment materials to form a piped binding or upon the surface of such materials for ornamental purposes. More particularly, it relates to that class of attachments in which the stitching is concealed within the folds of the piping so that it is not visible on the normally viewed outer surface.

This manufacture is done in one operation by utilizing a folder which bends the longitudinal edges of the stripinto reverse folds and then into U form. If desired, while in this U form, an additional layer of material such as the raw edge of the bottom of a skirt may be inserted between the folded over edges and then stitched together. By feeding the folded over strip to the needle so that only the inner ply ofthe top fold is nipped, and then directing theneedle through the remaining plies, it is possible to obtain an effect in which the stitching does not show on the outer or right side of the fabric. Apparatus whereby this may be accompl-ished has been shown in the patent to Seaman and Braf, 1,756,036 of April 29, 1930, and in the patent to Sigoda 2,527,582, of October 31, 1950.

When attachments as disclosed in said patents are operated at comparatively slow speeds, satisfactory results are obtained. However when the speed of operation is raised, as has become increasingly necessary in these days of high speed production, several difiiculties :are met which prevent successful operation. In pending continuation application Serial No. 373,850, filed August 12, 1953 (originally filed as Serial No. 168,355

on June 15, 1950, of which this is a continuation-inpart), the problems encountered due to undesired needle .defiections arising in high speed machine operation which .cause the needle point to dance about in an irregular pattern, are discussed, and corrective means are disclosed.

In pending application Serial No. 306,631, filed Aug- :ust 27, 1952, of which this is also a continuation-in-part, *Ithrea-d breakage resulting from nipping of the thread by 'the needle point as the thread is whipped about during 'high speed operation is discussed and means to counter- .act this by shifting the line of stitching are disclosed.

Previous efforts in this field have been directed to mounting the shoe over which the folded plies are bent for 'needle penetration on a flat spring, the theory being that the resilient mounting allows the needle to rub against the shoe through the work and deflect the spring 'sufliciently so that accuracy of positioning of the nose of the shoe 'with respect to the needle is not too critical. At slow speeds, it may be "appreciated that the slowly descending needle can move the shoe sufficiently with out harmful effects. However, as the. speed of operation is increased, it is found that such a degree of accuracy cannot be tolerated and increasingly finer means assrsoz Patented Aug. 6, 1957 ice of adjusting the position of the nose of theshoe with respect to the needle have been resorted to. A

One fault inherent in the resilient mounting of the shoe which was not recognized at slow speeds because it did not show up, was that machine vibration shock excites the flat spring into oscillation of a non-uniform and varying nature resulting in flexing; and warping of the flat spring section supporting the shoe and conse'- quent fluctuating shifting of the position of the shoe nose with respect to the needle. Unsatisfactory needle pene tration and thread and needle breakage therefore occur with such frequency as to make such. shoe mountings unsuitable for high speed operation.

This fault was recognized and the rigid mounting of the shoe (and the folder) shown in Serial No. 373,850 was devised. While it was an object to provide the great convenience of an attachment readily, detachable from the foot-bar as a whole, there was the further advantage that the rigid mounting of the footbar and its constant relationship to the needle bar would, help maintain the accuracy of registration between the nose of the shoe, the folder outlet and the needle required for high speed operation. While provisions have always been made for initially positioning these cooperating elements with respect to each other, the preservation of their spatial foot-bar guide bushings from machine to machine.

In some machines this maybe due to the tolerances set in manufacturing and in others it is undoubtedly due to subsequent wear or abuse. The net effect is that the foot-bar tends to move about its axis acrossthe line of feed and to and from the needle at high operating speeds and this is fatal to successful operation of the device. This shifting of the presser foot-bar is not constant and is only of a small magnitude. However when it is borne in mind that the desired needle penetrations must take place within a fabric which is literally less than the thickness of two hairs and that the section of the needle about its eye is usually greater than the section of the material being penetrated or nipped, control of this shift is seen to be critical for securing successful results at high speeds. This undesired shift nullifies the initial fine and painstaking adjustment of the positions of the folder outlet and the nose of the presser shoe with respect to the needle and thread or needle breakage or improper stitch penetration ensues.

The play in the guide bushings also permits some shifting of the position of the attachment as a Whole due to the feed action of the machine. The position of the folder outlet is particularly affected. This shifting is occasioned by the differences in section or bulk of the binding tape, particularly at seams in the tape, which exert a varying pressure between folder outlet and the nose of the shoe not only when passing about the nose but even as it proceeds under the sole of the shoe, producing more or less rearward deflection of the foot-bar and consequent shifting of the folder outlet.

In addition it has been found that the foot-bar mounting of the attachment is not of advantage in the sewing of thickened sections of the folded binding as not only must the pressure of the foot-bar spring be overcome, but the cocking and binding of the foot-bar in its guide bushings permitted by such play must also be counteracted. This binding occurs because the thickened seam a portion first seeks to raise the foot-bar from a position just under the shoe nose which is somewhat ahead of the foot-bar, axis instead of being directly under it.

i It has therefore been a principal object to provide a separate mounting of the presser shoe independent of the foot-bar and the folder while retaining all the advantages of the rigid shoe mounting disclosed in the pending applications for the purpose of eliminating the difiiculties occasioned by excessive play encountered in foot-bar guide bushings from machine to machine.

It has been a further object to provide a separate and independent mounting of the folder to make it immune from the effects of the shifting of the foot-bar and the effects of the feed action. It has been another object to obtain relative constancy of spacing after adjustment between the presser shoe nose and the folder outlet by means of the new arrangement disclosed herein.

- This' new arrangement consists of separate pivotal mountings for the presser shoe and the folder based on the neddle plate which are completely independent of the foot-bar and each other. Thus undesired foot-bar movements no longer afiec t the precise positioning of the presser shoe and the folder outlet and their respective adjusted positions remain constant. This permits uninterrupted high-speed blindstitching.

This reorganization is such that the pressure exerted by the foot bar spring can still be transmitted to the presser shoe to ensure positive feed action and the presser shoe may be raised by the elevation of the feed dog during part of the feed stroke. However, the folder out-let is now maintained; a selected distance above the needle plate so that the nose of the presser shoe cannot normally contact the folder outlet even during its cyclic elevation by the feed dog. This produces an unexpected material pulldown through the folder which occurs after the end of each feed stroke of the feed dog and an improved presentation of the folded plies to the needle so that better needle penetration is obtained. j The pivotal mounting of the presser shoe also provides a mechanical advantage which facilitates lifting of the foot 'bar by thickened seam sections.

Fig. is a similar view, showing how the raising of the- -feed dog tilts the presser shoe upwardly against the pressure of the foot bar spring, the feed dog being at that part of the feed cycle when it is fully raised and, is just starting to move the work rearwardly;

Fig.6 is a similar view, the feed dog having reached the end of its rearward travel just before it descends below the needle plate for its return to the position shown in Fig. 4; v

Fig. 7 is a cross-sectional view taken on line 77 of Fig. 2 showing the folded strip within the folder;

Fig. 8 is a longitudinal cross-section taken on line 88 .cf Fig. 2;

Fig. 9 is a cross-sectional view of the folder taken on line 99 of Fig. 2, showing the fabric strip edge folded by the folder bends;

Fig. 10 is a similar cr-osssectional view of the folder and the folded strip taken on line 1tl1tl of Fig. 2;

Fig. 11 is an enlarged, fragmentary, perspective view of the outlet end of the folder;

:Fig. 12 is a similar view showing how the folded strip emerges from the outlet of the folder and how the folded edges are disposed vertically as they pass about the end of the presser-shoe in position for the needle penetration;

Fig. 13 is a similar view showing the needle as it just begins to penetrate the innermost fabric ply;

Fig. 14 is a similar view showing the needle after penetration of the innermost ply and the lower plies;

Fig. 15 is a detail view, partly in cross-section, showing the blindstitched piping as it would be sewn to the edge of a garment; and

Fig. 16 is a detail view in cross-section showing the eccentric adjusting means for moving the folder outlet to and from the needle.

Only those portions of the base 10 and the needle head 11 of the standard sewing machine which are necessary for comprehension of the invention are shown. The head carries the usual needle bar 12 and pointed needle 14 and the presser foot bar 15. Bar 15 may be raised to disengage the presser shoe from the work when necessary by manipulation of the usual lift lever 16. Foot pressure spring 17 urging bar 15 downwardly, and pressure adjusting bushing 18 which may be manipulated to adjust the elevation of the shoe for work of differing bulk, are of conventional and well known construction and function.

Base 10 carries the usual needle plate 19 provided with needle hole 2%, feed dog slots 21, and screw holes 22 by which the needle plate is secured to the machine bed 10. Feed dog 23 operates through slots 21 to cooperate with the sole of the presser shoe portion of the device to feed the work in the usual manner. Feed dog 23 travels in the usual four motion path through conventional mechanism (not shown) of well known construction and operation.

The attachment 25 includes a support yoke 26 which is secured to needle plate 19 by rivets 27 or by any equivalent means. Yoke 26 has two rearwardly disposed arms 28 in which pin 29 is journalled horizontally. Folder supporting member 30 which is pivotally mounted between arms 28 freely on pin 29, has a vertically disposed socket 31 for retaining spring 32 which bears on rearwardly extending tongue 34 of support yoke 26 to urge folder supporting section 35 of member 3% downwardly toward needle plate 19. Set-screw 36 vertically threaded into member 30 at about its central portion, limits the downward excursion of section 35, while lock-rut 37 secures set-screw 36 in its adjusted position.

Member 30, once set-screw 36 is set, therefore cannot move downwardly but is capable of upward, pivotal move ment about pin 29 against the tension of spring 32.

This upward movement occurs when the lift lever 16 is raised for the insertion of work beneath the presser shoe. As the presser shoe is raised, it engages the under surface of the folder and raises the folder with it. Lateral movement in a horizontal plane by member 30 is prevented by its mounting on pin 29 between yoke arms 28. This rigidity in mounting is of advantage in maintaining proper needle penetration of the folded plies at high operating speeds.

The presser shoe portion 38 of the attachment is also pivotally supported on pin 29 by an arm 39 having a tapped hole 40 into which the threaded end 41 of pin 29 is .screwed. Since pin 29 may turn in arms 28, while member 30 and arm 39 are both mounted on pin 29, each is independent of the other in its pivotal movement about pin 29.

Arm 39 is either attached to or integral with presser shoe support member 42 which is provided at its bottom with an inverted, male T-section 44 on which a mating T-slotted section 45 of shoe portion 46 is mounted so that the latter is supported in fixed vertical position, but so that it may be moved horizontally as required to or from the needle 14. Member 42 has a recess 48 in which compression spring 49 is retained. One end of spring 49 bears on the inner face of recess 48 and the other end bears on a projecting lug 50 of shoe portion 46 when the parts are assembled. Spring 49 therefore serves to press shoe portion 46 rearwardly.

Thumbsc'rew 51 is threaded into a rear, upstanding projection 52 of support member 42 and has a tapered, conical point 54 which bears against sloping wall 55 of lug 50. Manipulation of thumbscrew 51 can thus move' shoe portion 46 forwardly against the tension exerted by spring 49 as the tapered point 54 is moved downwardly against lug 50.

Since the tapered conical point 54 bears against sloping wall 55 at an angle, as thumbs'crew 51 is screwed downwardly, the forward movement of the shoe portion 46 will be very gradual and capable of micrometric calibration. Calibrating numerals 56 are therefore inscribed about the barrel portion 57 of thumb'sc'rew 51 and reference line 58 is inscribed on the front surface of projection 52.

Presser shoe support member 42 has an upstanding rojection 59 which has a horizontally disposed slot 60 to receive stud pin 61 which is screwed into presser foot bar 15. Shoe portion 46 may thus be raised or lowered on the work by means of hand lift lever 16. The end of presser foot bar bears on the top surface 62 of presser shoe support member 42 under the pressure exerted by spring 17. Surface 62 may be heat treated to resist the wear of the continual impact of the end of bar 15 or a wear resisting member may be inserted between the contac'ting surfaces for the same purpose.

Shoe portion 46 has a nose 64 over which the folded plies are positioned for needle penetration as will be more fully described subsequently.

Side wall 65 of member 42 has a horizontally disposed slot 66 in which folder'outlet positioning lug 67 is adjustably retained by screw 68 which locks it in its adjusted position. Lug 67 limits the location of the folder outlet with respect to needle 14 in a plane parallel to the line of feed independently of any adjustment of the position of presser shoe nose 64 withrespect to the needle.

Folder 70 is mounted on the tang shaped end of folder supporting section 35 of member by an arrangement which facilitates adjustment in the horizontal plane of the position of folder outlet 71 with respect to needle 14;. Folding and tape guiding portion 72.0f folder 701s secured to mounting bracket portion 74 by soldering or any other equivalent means. Bracket portion 74 is provided with slot 75 lying parallel lengthwise with folding and guiding portion 72 through which slot, screw 76 may be secured to section35. A second slot 78 perpendicularly disposed to slot 75 receives the eccentric shoulder 79 of folder positioning screw 80. Screw 80 has an extension 81 having a peripheral groove 82 in which lockring 84 is fitted to hold screw 80 in assembled position on section 35. 1

When screw 76 is loose, rotation of screw 80 in slot 78; causes folder 70 to move as a whole on section laterally to and from needle 14. Tightening screw 76 will lock folder portion 70 in adjusted position.

Adjustment of the location of folder outlet 71 toand from the needle on a line substantially parallel to the line of stitching is accomplished by loosening screws 76 and 68 in that order andmoving lug 67 manually to position folder outlet 71 as required, after which screws 68 and 76 areretightened in sequence.

These adjustments for locating folder outlet 71 with rep'ect to needle 14 are desirableto permitoptim'um positioning of the folded plies for proper needle penetration for the blind-stitching operation to accommodate various fabrics of differing thickness which may be encountered from time to time.

Referring to Figs. 7, 9, and 10, the fabric folding and guiding portion 72 is provided with suitable internal bends $5 which cause the strip edges to fold over longitudinally as the strip is drawn through the bends toward the needle by the feed action of the machine for thesubsequent blindstitching operation.

Platform 86 secured to folder 70 acts as a support over which a piece of material, such as typically the raw edge of the skirt of a garment, may pass to be bound by the 6 j j fabric :strip which is folded in the folding and guiding portion 72. Fig. 15 shows a typical form of this work in which such a binding has been applied to a garment edge by the blindstitch operation. The folder itself is conventional and forms no part of the invention.

The method of producing the blindstitching with this attachment is substantially similar to that utilized in the device shown in the Seaman and Braf patent previously referred to. The outlet end 71 of folder 72 is shown in Fig. 11, and in Fig. 12, the folded over strip is shown as it just leaves outlet 71, which is purposely mounted at a fixed height above nose 64 so that the folded strip in leaving outlet 71 to pass about nose 64 now assumes a substantially vertical position in a plane parallel to that of the needle path. This is best shown in Figs. 4, 5 i

and 6.

By proper positioning of outlet 71 with respectto needle 14 as previously described to compensate for the partic* ular fabric being stitched, the folded plies will lay in the path of travel of the needle. As the position of nose 64 is adjusted horizontally with respect to the needle by manipulation of thumbscrew 51, the location of the upright section of the folded strip will be adjusted so that the needle may intercept various of the strip plies. If it is desired to produce a blindstitch, the position of nose 64 is adjusted so that the needle will pass through the innermost ply of the top fold of the fabric strip. This is shown in Fig. 13. Hence the stitching will not show through on the outer surface of this top ply.

After passing through these plies as shown in Fig. 14, the needle continues to pass downwardly through the remaining plies to form the usual stitch locking the folded over strip into a tube or piping. The stitched piping then passes around the edge of nose 64 and under the bottom surface of shoe portion 46 which functions as the usual presser shoe. In conjunction with the feed dog 23, the sewn work is drawn rearwardly from. the machine in the usual manner.

However the usual feed action of the machine is supplemented by an additional pulldown of the folded plies through the folder which is produced in the following manner.

Reference to Fig. 7 shows that folder support member 35 is rigidly mounted on needle plate 19 and cannot move downwardly because of the fixed, minimum clearance above the needle plate established by the adjusted position of set-screw 36.

From Figs. 4, 5, and 6, however, it will be noted that the vertical position of nose 64 changes with respect to folder outlet 71 during a portion of the feed cycle. This movement takes place on an arcuate path described about end 41 of pivot pin 29 and is caused by the lift component of the four motion feed action applied through feed dog 23 by the usual feed mechanism of the sewing machine. This lift component causes foot-bar pressure spring 17 to be compressed.

In Fig. 4, no lift movement is exerted on presser shoe 46. In Fig. 5, the teeth of feed dog 23 have been elevated above the surface of needle plate 19 and feed dog .23 has just begun its rearward travel carrying the sewn work with it. As feed dog 23 continues rearwardly, presser shoe 46 continues to rise about its pivot until,

as shown in Fig. 6, at the end of the rearward travel of feed dog 23, presser shoe 46 is at its highest inclination- The rearward feed action of feed dog 23 stops at this instant and feed dog 23 then descends below the level'.

portion of the folded plies through the folder. This is an additional feed action not obtained from the usual action of the machines feed elements.

This material pulldown results in more effective needle 7 penetration of the plies folded about the presser shoe nose because these folds are looser and softer. This freeing of the folds takes place because, referring to Fig. 6, the work is clampedbetween the rearmost end of presser shoe 46 and the needle plate as feed dog 23 begins its descent. At that instant, nose 64 is still elevated above the needle plate 19 because of the pivotal mounting of arm 39. Nose 64 being further from the axis of movement must travel a greater distance to reach needle plate 19 and this additional travel draws an additional amount of strip through the folder. When the folded plies relax from the stretching caused by this action, the folds that are presented to the needle for nipping are easier to penetrate. Without this additional pulldown, the folded plies are presented to the point of the needle at a very steep angle because the material is held tautly between the folder outlet and the nose of the nose about which it is tightly wrapped, in the conventional arrangement. The angle of attack which the needle point may then take is almost parallel to the axis of the needle and the point of the needle may be more easily deflected from nipping the ply. Under such conditions the positioning of nose 64 is so critical that any displacements of either the needle or the presser shoe nose which occur at high speeds may result in imperfect sewing or a broken or dulled needle. When the folds are looser and softer about nose 64, as is the case in this new arrangement, the angle of attack which the needle may take is not so steep and the material being looser may be slightly depressed by the needle point as it descends to find the best entry for proper nipping action.

When the presser shoe nose 64 and the folder outlet 71 are not held separated, there can be no relative movement between them which will provide this freeing of the folds about the presser shoe nose. In the previous constructions, the folder outlet either rested directly on the presser shoe nose or travelled with the nose in the same relative position so that there never could be any relative movement between them.

Improved handling of thickened sections of the folded L plies occurs because of the pivoted, rigid mounting of the presser shoe. The pivotal mounting produces a V-shaped opening into which the thickened portion may be more readily received so that the pressure shoe may be more easily raised thereby and also provides a mechanical advantage to assist in the action. The ultimate force for lifting the foot bar against the pressure of spring 17 is now applied substantially at the axis of the foot bar at its point of contact with surface 62. This tends to overcome the binding effect when the guide bushings are oversize or worn. The mechanical advantage results because the initial force for lifting the foot bar is applied to the front end (nose 64) of the longer arm of a lever made up of sections 39, 42 and 46 which has as its fulcrum the axis of pin 29. The ratio of the arms is represented by the ratio of the distance from the end of nose 64 to the axis of pin 29 to the distance from the point of contact on surface 62 by the foot bar to the axis of pin 29.

In the conventional structures in which the mount for the presser shoe is a flat spring, the flat spring construction is a great disadvantage because since it is flexible, thethickened section when it first comes into contact with the nose and subsequently as it travels beneath it, can cause twisting and distortion of the spring and such flexing of the spring under the rearward action of the feed that nose of the shoe can actually move rearwardly as a thickened section passes around and beneath the presser shoe. As this action continues after the thickened section has passed about the presser shoe nose, a considerable section of the strip may be improperly sewn.

While the presently preferred embodiment has been described in detail for the purpose of illustration, it is to be understood that the invention is not to be limited 8. to thedetails of construction shown and described, but is to be construed broadly within the spirit and scope of the appended claims. What is claimed is:

l. A- blindstitch attachment for use with a sewing machine having stitchforming mechanism, means for mounting a needle plate and a feed member having a rising and falling movement during a portion of the feed cycle: comprising a needle plate through which said feed member may move vertically during a portion of the feed cycle; a common pivotal mounting on said plate for a presser shoe and for a folder; a presser shoe carried by said pivotal mounting, having a blindstitch nose and resting upon said feed member passing through said needle plate when the attachment is mounted on the sewing machine; a folder carried byv said pivotal mounting, adapted to fold a fabricstrip and having an outlet from which said strip may emerge; said outlet being disposed above and in line with said nose so that the folded strip emerging therefrom is guided over the nose of the presser shoe for blindstitching by the stitchforming mechanism of the sewing machine; said presser shoe being arcuately movable about said common mounting with the rise and fall of said feed member; said folder also being arcuately movable about said common pivotal mounting, and means on said folder for maintaining the outlet of said folder out of contact with the nose of said shoe when relative movement between said folder outlet and said nose occurs.

2. A blindstitch attachment for use With a sewing machine having stitchforming mechanism, means for mounting a needle plate and a feed member having a rising and falling movement during a portion of the feed cycle: comprising a needle plate through which said feed member may move vertically during a portion of the feed cycle; a common pivotal mounting on said plate for a rigid, non-defiectible presser shoe support and for a folder support; a presser shoe support carried by said pivotal mounting; a presser shoe having a blindstitch nose, carried by said presser shoe support, said presser shoe resting upon said feed member passing through the needle plate when the attachment is mounted on the sewing machine; a folder support carried by said pivotal mounting;-a folder having an outlet, carried by said folder support, said folder being adapted to fold a fabric strip, the outlet of said folder being disposed above and in line with said nose so that the folded strip emerging therefrom is guided over the nose of the presser shoe for blindstitching by the stitchforming mechanism of the sewing machine; said presser shoe support being arcuately movable about said common mounting With the rise and fall of said feed member; said folder support also being arcuately movable about said common pivotal mounting, and means on said folder for maintaining the outlet of said folder out of contact with the nose of said shoe when relative movement between the folder outlet and the nose occurs.

3. A blindstitch attachment for use with a sewing machine having means for mounting a needle plate, and a feed member having a rising and falling movement: comprising a needle plate through which the feed member may move; a rigid, non-deflectible support pivotally mounted on said plate; a presser shoe having a blindstitch nose, carried by said support; said shoe resting periodically upon said feed member when the attachment is mounted on the machine and moving on an arcuate path about its mounting in accordance with the movement of the feed member; a rigid, non-deflectible support for a folder mounted on said needle plate; a folder having an outlet, carried thereby; the nose of said presser shoe being located closely adjacent'the outlet of said folder and between said outlet and said shoe in a vertical plane; and means on said folder for maintaining it out of contactwith the nose of the presser shoe as the latter moves about its pivotal mounting.

4. A blindstitch attachment for use with a sewing inachine having feed mechanism including a four motion feed dog having a vertical movement above and below the needle plate; comprising a needle plate through which the reed dog may pass; a yoke secured to said plate; a folder support freely mounted on said yoke; resilient means urging one end of said folder support downwardly toward said plate; a stop on said folder limiting movement of said end downwardly toward said plate; a folder having an outlet carried by said end of the folder support; a presser shoe support pivotally mounted on said yoke; a presser shoe having a blindstitch nose carried by said presser shoe support; said nose being disposed closely adjacent the outlet of said folder and between said outlet and said plate in a vertical plane; said shoe moving about its pivotal moutning in accordance with the vertical movements of the feed dog through said plate when the attachment is mounted on the machine; the downward movement of said shoe producing an extra pull on the work emerging from the folder outlet beyond that normally produced by the usual action of the feed mechanism.

5. A blindstitch atttachment for use with a sewing machine having stitchforming mechanism including a needle and a needle plate, and feed mechanism including a fourmotion feed dog having a vertical movement above and below the needle plate during a portion of the feed cycle: comprising a plate adapted to replace the needle plate and through which the feed dog may pass; a yoke secured to said plate; a shaft freely journalled in said yoke; a folder support freely mounted on said shaft; resilient means urging one endof said folder support downwardly toward said plate; a stop limiting movement of said end downwardly toward said plate; a folder having an outlet carried by said end of the folder support; the outlet of said folder being adjacent the path of travel of the needle when the attachment is mounted on the machine; said folder outlet being spaced above said plate; a rigid, nondeflectible pressure shoe support pivotally mounted on said shaft; a presser shoe having a blindstitch nose carried by said presser shoe support; said nose being disposed closely adjacent the path of travel of said needle when the attachment is mounted on the machine and closely adjacent the outlet of said folder and between said outlet and said plate in a vertical plane; said shoe resting upon said feed dog passing through the plate when the attachment is mounted on the machine and moving about its pivotal mounting in accordance with the vertical movements of the feed dog during a portion of the feed cycle; the downward movement of said shoe producing an extra pull on the work emerging from the folder outlet beyond that normally produced by the usual action of the feed mechanism when the attachment is mounted on the machine and the machine is operated.

6. A blindstitch attachment for use with a sewing machine having means for mounting a needle plate and feed mechanism including a foot-bar and a spring urging said foot-bar downwardly in a vertical direction: comprising a base for the attachment adapted to be mounted on the machine in place of the needle plate; a support for a presser shoe on said base; a support for a folder also on said base; said shoe support and said folder support being independently disposed on a common, horizontal, pivotal mounting on said base for arcuate movement of one with respect to the other; a presser shoe having a blindstitch nose carried by said presser shoe support; a folder having an outlet can'ied by said folder support; means on said folder support for maintaining the outlet of said folder in a position above the nose of said shoe; and a connection between said presser shoe support and said foot-bar adapted to transmit the upward and downward movements of said bar without transmitting any of the horizontal movements thereof when the attachment is mounted on the machine.

7. A blindstitch attachment for use with a sewing machine having means for mounting a needle plate and feed mechanism including a foot-bar having a horizontally extending stud shaft near its lower extremity, and a spring prging said footbar downwardly in a vertical direction: comprising abase for the attachment adapted to be mounted on the machine in place of the needle plate; a support for a presser shoe on said base; a support for a folder also on said base; said shoe support and said folder support being independently disposed on a common, horizontal, pivotal mounting on said base for arcuate movement of one with respect to the other; a presser slide having a blindstitch nose carried by said presser shoe support; a folder having an outlet, carried by said folder support; means on said folder support for maintenance of the outlet of said folder in a position above the nose of said shoe; and a connection between said presser shoe support and said foot-bar adapted to transmu; the upward and downward movements of said bar without transmitting any of the horizontal movements thereof when the attachment is mounted on the machine, comprising a horizontally disposed slot in said presser shoe support in which said stud shaft on the foot-bar is freely received.

8. A blindstitch attachment for use with a sewing machine having feed mechanism including a four-motion feed dog having a vertical movement above and below the needle plate and a presser foot-bar resiliently urged downwardly toward the feed dog; comprising a needle plate through which the feed dog may pass; a yoke secured to said plate; a folder support freely mounted on said yoke; resilient means urging one end of said folder support downwardly toward said plate; a stop limiting movement of said end downwardly toward said plate; a folder having an outlet carried by said end of the folder support; a presser shoe support pivotally mounted on said yoke; a presser shoe having a blindstitch nose, carried by said presser shoe support; said nose being disposed closely adjacent the outlet of said folder and between said outlet and said plate in a vertical plane; said shoe moving about its pivotal mounting in accordance with the vertical movements of the feed dog through the plate when the attach ment is mounted on the machine; the downward movement of said shoe producing an extra pull on the work emerging from the folder outlet beyond that normally produced by the usual action of the feed mechanism; a connection between said presser shoe support and said presser foot-bar adapted to transmit only the upward and downward movements of said bar without transmitting any of the horizontal movements thereof; and means for horizontally adjusting the position of the nose of said shoe.

9. A blindstitch attachment for use with a sewing machine having feed mechanism including a four-motion feed dog having a vertical movement above and below the needle plate and a presser foot-bar resiliently urged downwardly toward the feed dog: comprising a needle plate through which the feed dog may pass; a yoke secured to said plate; a folder support freely mounted on said yoke; resilient means urging one end of said folder support downwardly toward said plate; a stop limiting movement of said end downwardly toward said plate, comprising a member adjustably secured to said folder support, the lower end of said member being in contact with said plate; a folder having an outlet, carried by said end of the folder support; a presser shoe support pivotally mounted on said yoke; a presser shoe having a blindstitch nose carried by said presser shoe support;

said nose being disposed closely adjacent the outlet of said folder and between said outlet and said plate in a vertical plane; said shoe moving about its pivotal mounting in accordance with the vertical movements of the feed dog through said plate when the attachment is mounted on the machine; the downward movement of said shoe producing an extra pull on the work emerging from the folder outlet beyond that normally produced by the usual action of the feed mechanism; a connection between said References Cited in the file of this patent UNITED STATES PATENTS 1,756,036 Seaman et a1 Apr. 29, 1930 0 A'u'erbach Dec. 15, 1931 Seaman Dec. 1, 1936 Seaman Sept. 13, 1938 Knaus May 4, 19 48 Johnson et al. Feb. 3, 1953

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