US3747544A

US3747544A - Sewing machine with improved binder-feed arrangement

Info

Publication number: US3747544A
Application number: US00244780A
Authority: US
Inventors: K Nicolay; H Goldbeck
Original assignee: Duerkoppwerke GmbH
Current assignee: Duerkoppwerke GmbH
Priority date: 1971-05-11
Filing date: 1972-04-17
Publication date: 1973-07-24
Anticipated expiration: 1990-07-24
Also published as: DE2123160A1; IT954987B; GB1343098A; FR2139283A5

Abstract

A double-needle sewing machine for the stitching of bound or piped slits in a fabric workpiece, e.g. a buttonhole or pocket slit in a piece of fabric adapted to form part of a coat or like outer garment, is provided with a feed arrangement for the binder strip designed to fold the latter into an inverted-T configuration. The latter arrangement is subdivided into a plurality of guide portions and a clamping device so that a portion proximal to the sewing machine may continue to feed the binder strips while a portion remote from the needles can be released to receive the binder strip for the next operating cycle.

Description

United States Patent 1 Nicolay et al.

[451 July 24, 1973 p SEWING MACHINE WITH IMPROVED BINDER-FEED ARRANGEMENT [75] Inventors: Karl Nicolay, Bielefeld; Heniz Goldbeck, Brackwede/Westf, both of Germany [73] Assignee: Durkoppwerke GmbH, Bielefeld,

Germany 22 Filed: Apr. 17, 1972 21 Appl. No.: 244,780

[30] Foreign Application Priority Data May 11, 1971 Germany P 2123 160.7

[56] References Cited UNITED STATES PATENTS 6/1970 Miller 112/152 X Lopez 112/65 Hester 112/152 ABSTRACT A double-needle sewing machine for the stitching of bound or piped slits in a fabric workpiece, e.g. a buttonhole or pocket slit in a piece of fabric adapted to form part of a coat or like outer garment, is provided with a feed arrangement for the binder strip designed to fold the latter into an inverted T configuration. The latter arrangement is subdivided into a plurality of guide portions and a clamping device so that a portion proximal to the sewing machine may continue to feed the binder strips while a portion remote from the needles can be released to receive the binder strip for the next operating cycle.

10 Claims, 2 Drawing Figures SEWING MACHINE WITH IMPROVED BINDER-FEED ARRANGEMENT FIELD OF THE INVENTION BACKGROUND OF THE INVENTION In the preparation of bound or piped openings in a fabric garment, it has been the practice heretofore to feed a binder strip, folded by appropriate guides, to a stitching site and to provide two rows of stitching which are adapted to flank a slit cut into the fabric and forming the opening. In practice, the binder strip and the fabric workpiece are advanced together past the needles of the sewing machine, the binder strip being applied to the surface of the workpiece immediately ahead of the stitchforming means. The fabric workpiece or main piece of fabric may lie upon the stitching plate or table of the sewing machine while the binder or piping material is fed to the surface of the workpiece from above, the folding and feed means being elevated to allow positioning of the binder strip and thereafter pressing against the binder strip and the workpiece to hold it in place. The entire feed arrangement may be sidplaced in accordance with the operating cycle of the operating machine to advance them past the needles.

In conventional apparatus of this type, the binder strips must be individually positioned before sewing and the entire binder-feed arrangement must remain in the clamping or pressing position during the entire stitching operation. As a consequence, delays are encountered between sewing cycles and it is not possible to prepare a new binder strip or fabric workpiece without releasing the clamping and folding arrangement for the prior binder strip and its workpiece. The duration of each cycle is, therefore, relatively long and the rate at which successive cycles can be carried out is limited not only by the sewing time but also by the hiatus in operation of the feed arrangement necessary for preparation of the material for the next sewing cycle.

OBJECTS OF THE INVENTION It is, therefore, the principal object of the present invention to provide an improved apparatus for sewing bound slit-like openings in a fabric workpiece. A more specific object of the invention is the provision of an apparatus for binding or piping the edges of a slit-like opening, e.g. adapted to form a buttonhole, pocket or the like whereby the aforementioned disadvantages can be obviated.

Yet another object of the invention is to provide an apparatus for the sewing of bound pocket openings, buttonholes or the like in a fabric workpiece, especially a piece of material adapted to form part of an outer garment such as a sack coat, by improving the feeding of the binder strip and the folding thereof during the sewing operation.

Yet a further object of our invention is the provision of an improved apparatus of the general class described, having increased output and operating rate.

SUMMARY OF THE INVENTION These objects and others which will become apparent hereinafter, are attained, in accordance with the present invention, which provides a sewing machine for stitching the borders of a slit-like opening, e.g. a buttonhole or pocket opening, with a binder strip so as to reduce the dead time of the sewing machine and the fabric-fed apparatus by subdividing the binder-feed mechanism into a plurality of folding and clamping portions which may be operated independently so that the portion proximal to the sewing site may remain effective in the feeding of one binder strip to the sewing needles while another portion of the feeding mechanism upstream therefrom can be released (without releasing the portion proximal to the needles) to accommodate the next binder strip.

In other words, the dead time of the apparatus is reduced and the operating rate or output increased by a system which, during the working cycle of the sewing machine (i.e. during the sewing of a prior binder strip to the workpiece) the feed arrangement or apparatus provides a free space for the positioning and arrangement of a fabric workpiece and/or the next binder strip, whereby the next cycle may commence immediately after the previous stitching cycle without any time loss for arrangement of the workpiece or binder strips.

According to an important feature of the invention, the workpiece-feed system includes an elongated member adapted to ride upon the worktable or stitching plate and shiftable parallel to the slit or opening to be formed, or previously formed, in the workpiece and transversely to the plane of a pair of needles adapted to stitch opposite sides of the slit. The elongated member displaces the workpiece toward the stitching site and co-operates with a binder-folding orientation or clamping arrangement which is subdivided in the manner described while being provided with means for raising and lowering all or a portion of the latter arrangement to receive and hold the fabric material.

In other words, the apparatus may comprise a sewing machine forming a stitching site and a workpiecereceiving table or plate upstream from the stitching side while the elongated member bridges these two sites and may have a length in the direction of fabric feed equal approximately to the length of the workpiece. Co-operating therewith, there is a clamping device and a pair of folding rails each having a respective mechanism for raising and lowering same and independently operable at least within limits to allow insertion of the binder strip in the rail upstream from the stitching site while a rail portion thereof downstream from the stitching site continues to guide the previous length of binder. The two portions of the folding rail are thus provided in tandem, i.e. one behind the other, at the upstream site of the sewing machine and are independently elevatable and lowerable.

The device according to the invention thus enables the operator to position a second workpiece and binder strip at the free space to the upstream side of the sewing machine while the previous workpiece and binder strip are stitched together as they advanced by the feed mechanism past the stitching site. The dead time of the machine can thus be practically reduced to zero as indicated earlier and the operator remains active throughout the period of machine use.

DESCRIPTION OF THE DRAWING The above and other objects, features and advantages of the present invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG. 1 is a somewhat diagrammatic vertical elevational view of the apparatus as seen looking toward the head of the sewing machine; and

FIG. 2 is a perspective view from above of a portion of this apparatus.

SPECIFIC DESCRIPTION The apparatus described and illustrated in connection with FIG. 1 and 2 may be used for the production of stitched slit-like openings in an outer-garment fabric such as a sackcoat. To this end, the sewing machine may be provided with a main cutting means and second cutting means may be disposed below the table for producing short incisions at each end of the main incision or slit to connect the main incision with each end of a stitch row paralleling the main incision. In general, the stitch rows will be of the same length and will start approximately simultaneously when the pocket opening is to be parallel to an edge or edge seam of the fabric piece. However, when the pocket opening is to be inclined to the edge or edge seam, one stitch row will commence before the other stitch row, i.e. the stitch rows will be of the same length but longitudinally offset from one another. The main incision or slit between these stitch rows will generally be of a length shorter than the length of the stitch rows and will terminate in Y-shaped slits, whose incisions connect each end of the main incision to the respective end of a stitch row.

The stitch rows are formed by a pair of needles which may be provided with control means for independent actuation so that, for example, one needle may be operated before the other to provide the longitudinal offset described above. The main cutting means may be a blade disposed upon the sewing machine head and extending between the two stitch rows to provide the main incision parallel to these rows. The other cutting means may include a pair of angle cutters located on a common support below the stitch plate or work table and adjustable in accordance with the angle of inclination of the main slit and the stitch rows to the edge or each seam so that the length of these incisions of each Y is adjusted in accordance with the angle to provide a clean bond opening. Furthermore, each of the angle cutters may include blades pivotally mounted at the apex of a wedge-shaped pin upstanding from a support and provided with actuating means for swinging these blades through angles determining the length of the respective incisions as the support is raised and lowered by a pneumatic cylinder. The control means may include a further pneumatic cylinder connected with a slidable bar whose position determines the excursions of the blades and which operates against a spring means via a pneumatic cylinder. The displacement of the slide bar may be determined by an adjustable abutment means adapted to set the angle of the main slit and stitch rows in accordance with the incision length and vice versa. A single programmer is provided for the incision length and slit angle. Such structure has been fully described in the commonly assigned copending application Ser. No. 244,781 entitled SEWING APPA- RATUS FOR THE FORMATION OF EDGE-PIPING OPENINGS.

Reverting to FIGS. 1 and 2 of the present drawing, it will be apparent that the apparatus comprises a support 1 and a table 2 which forms the stitch plate and a surface 20 across which the fabric workpiece is displaceable. A sewing machine 3 is mounted upon a support 1 and the plate 2 and comprises the usual post 3a with the operating mechanism for the needles and any stitch-forming devices below the stitch plate, a drive wheel 3b, connected to a drive source for the apparatus such as an electric motor by a clutch or other conventional coupling, an arm 3c overhanging the table and a head 3d disposed along the path of the workpieces but thereabove. The head 3d is provided with a pair of vertically reciprocable needle bars whose needles are shown in 3e and 3f and may be independently actuatable for the reasons described above. In addition, a cutting blade may be mounted at 3g to slit the workpiece between the stitch rows formed by the needles 3e and 3f. At the head 3d of the sewing machine, moreover, a guide 3h is provided. The guide 3h has a bifurcated, downwardly open configuration to form a channel 3i through which the binder material is guided and designed to hold the binder strip in an inverted-T orientation against the surface 321' of a guide member which is described in greater detail hereinafter.

The sewing machine may also comprise a conventional means for cutting the sewing thread automatically. It includes the previously mentioned blade for incising the workpiece to produce the main slit, the drive motor which is not illustrated but is connected to the drive at 31) by an engageable and disengageable clutch and the handwheel 3b which serves for positioning of the needle. If the motor is represented at M, therefore, it may be operated by a programmer P together with the various pneumatic and/or hydraulic and/or electrical devices for the workpiece-feed mechanism. The clutch between the motor M and the sewing machine 3 is represented at C The motor M is continuously driven during the operating period of the apparatus and the programmer P may reversibly connect the motor to the V-belt pulley 4 via a further clutch C The pulley 4 is connected to a threaded spindle or lead screw for driving the fabric feed apparatus here represented generally at 6.

The spindle 5 is'journaled at one end in a bearing plate 7 which may be mounted upon the sewing machine 3 while the other end of the spindle is received in a bearing plate 8 which is similarly supported on the table, e.g. via an adjustment device 8a for correct positioning of the height of the assembly 5,6,7,8. The bearing plate 7 and 8 carry a pair of rails 9 and 10 which extend horizontally parallel to one another in spacedapart relationship and are parallel to the spindle 5. The rails 9 and 10 slidingly support a carriage ll which'is driven by the spindle 5 and is connected to the fabricfed mechanism 6 via a linkage shown generally at 12.

In FIG. I, the total horizontal excursion of the carriage 11 has been foreshortened but is represented by the stroke X which must correspond at least to the stroke XI of the feed device 6 and, therefore, the approximate length of the workpiece to be handled. The stroke X1 also represents the displacement of the fabric-feed mechanism 6 during one working cycle.

Because of the large length of the spindle 5, we have found it to be advantageous to provide additional support therefore in the form of a rest 13. The spindle 5 is journaled in the center portion 13a of this rest while the upper and lower portions 13b and 130 of this rest are slidably mounted upon the rails and 9 respectively. When the carriage 11 is shifted to the right, the rest 13 is urged ahead of the carriage and is entrained on the return stroke by entrainment with the carriage 11 via an arm 11a.

In the working direction (A) corresponding to the direction of advance of the fabric, immediately ahead of the sewing machine 3, there is disposed above the table 2 and parallel thereto, a shaft 14 which is carried by an upright 16. The upright 16 comprises a post 16a (FIG. 2) in which the bar 16b is received, the shaft 14 being mounted on the bar 16b via a clamp 16c. The clamp 160 has a bifurcated end forming two lobes 16d and 162 which can be drawn together by screws 16f to tighten the clamp 160 against the bar 16b. The clamp 16c projects horizontally from the vertical post 16 and carries a horizontal bar 15 which is received in the opposite bifurcated end of clamp 16s, the lobes of this end being tightened by Allen screws 16f.

The clamp 16c can thus be raised and lowered along the post 16 to adjust the height of the bar 14 and can be swung about the axis of post 16 to align the workpiece-guide members with the needle site. The distance of the shaft 14 from the edge or edge seam of the fabric and from the edge of the table 2 can be adjusted by loosening the screws 16f and shifting the bar 15 accordingly. The bar 15 is provided at its extremity remote from the clamp 160, with a bifurcated clamp 15a consisting of a pair of lobes 15b and 15c forming an opening 15d in which the shaft 14 is received. The lobes 15b and 150 are spanned by bolts 15e which tighten and loosen the clamp around the shaft 14.

The shaft 14 carries

brackets

20, 21 and 22, each supporting a respective pheumatic cylinder 17, 18 or 19. For example, the bracket 20 comprises a plate 20a to which the sleeve 20b is affixed and which can be connected by the sleeve and its setscrew 200 with one end of the shaft 14 projecting forwardly beyond the clamp 15a. The plate 20a thus lies in a vertical plane. The plate 20a also carries a pair of horizontal blocks 20d and 20e in which the cylinder 17 and its piston rod 17a is guided in the lower block 20e and a sleeve 20f projecting downwardly therefrom. The lower block 20a is also provided with a stop pin 20g to control the stroke of the piston rod which is locked to a plate 17b by' screw 17c and thus operates against the force of a spring 17d. v

The pneumatic cylinder 17 is disposed immediately ahead of the sewing machine and is provided with an inverted-T profile folding guide 23 for the binder strip. The guide 23 is, more particularly, pivoted at 23a to a shoe 23b at the lower end of the piston rod 17a. When a binder strip is fed to the guide so that the central portion of the strip underlies the horizontal sole plate 231, the outer edges of the strip are bent around the edges 231a and 231b and then up along the flanks of the .L -shank. The fabric is held in place by the guide foot 3h mentioned earlier.

Similarly, the intermediate cylinder 18 is carried by a bracket 21 whose plate 210 has a sleeve 21b affixed to the shaft 14. The piston rod 18a is springbiased in the manner already described and carries the folding guide 24 which likewise is of .L -configuration. The bracket 22 most remote from the sewing machine has a pneumatic cylinder 19 whose piston rod 19a operates a clamping bar 25 for tensioning the binder strip.

The shaft 14 also carries a bent bar 26 which supports a plate 27 disposed below the clamping member 25 and extending only over part of the length of the guide 24. Pneumatic cylinder 17 lies generally perpendicular to the plate or table 2 while the pneumatic cylinders 18 and 19 are inclined at different angles to the table 2. The parts 24, 25 and 27 together constitute a binder-feed arrangement for the binder strip.

During a previous stitching cycle, the binder strip is placed upon the plate 27 and is clamped by a pneumatic cylinder 251 whose rod 252 rocks an actuator 253 to urge the shoe 254 against the binder strip. Below the plate 27, also during a previous stitching cycle, the main fabric piece, e.g. part ofa sack coat, is placed beneath the plate 27 and oriented with respect to the opening slit by optical markings by the operator or automatically. When, following the end of the earlier cycle, the fabric-feed arrangement 6 is elevated, and returned to the starting point, the fabric-feed shoes are lowered upon the workpiece under the control of the programmer P, simultaneously the clamp member 25 is lowered by its pneumatic cylinders 19 and the binder strip applied to the top of the fabric-feed device.

The fabric-feed device 6 comprises two longitudinally extending spaced-apart parallel rails or

shoe members

60 and 61, each of which is connected by three rods, representing the linkage 12, to a block 11b pivotal about the horizontal axis 11 1. The two

shoes

60 and 61, which have the cross-sections of right triangles with corresponding vertices turned toward one another, define a gap a between them which receives the i-shaped rail 24 and folds the binder upwardly around the upstanding web 24a of this guide. The approximately U-shaped binder strip is further folded by a pair of sheet-metal guide surfaces 62 and 63 upwardly to the inverted T-configuration. These forming strips 62 and 63 are provided with respective

pneumatic cylinders

64 and 65 which operate the bellcrank levers 66 and 67 fulcrumed on the

rail

60 and 61 so that these sheet-metal members are urged toward the gap a parallel to one another because of the guide slot 68 in which pins 69 of the strips 62 and 63 engage.

As the carriage 11 is shifted to the left, therefore, the main fabric layer and the binder strip thereon are simultaneously moved to the left, the binder strip being thereupon drawn off the guide 24 and onto the guide 23 which is slightly bent upwardly at its upstream end 231. While the binder strip continuesto be guided by member 23 and the sewing commences,,cylinders 18 and 19 can be relieved to preparethe next binder strip and fabric workpiece. The lengths of the'two folding rails 23 and 24 are so dimensioned that rail 24 can be lifted as soon as the sewing machine begins to stitch the new binder strip in place. Folding rail 23 is only relieved when the full sewing operation has been completed. The end 231 of the guide is thereby tilted upwardly to allow the next workpiece to be inserted.

While the main operating steps of the system have I been described previously, it should be noted that at the end of one cycle, the finished workpiece is drawn out from below the fabric-feed device 6 which is lifted from the fabric under the control of the programmer and by means not further illustrated. The fabric-feed device is then shifted to the right (FIGS. 1 and 2) in the elevated position to the region in which the next workpiece has already been positioned. The pneumatic cylinder 19 then applies the binder strip in the manner described and the clamp 27 is thereby released and raised whereupon the

cylinders

64 and 65 are operated by the programmer to fold the strip about the previously lowered guide rail 24. The fabric is then shifted in the direction of arrow A and the binder transferred to guide 23 as previously described. As soon as the transfer is made, member 24 is elevated and a fresh workpiece and binder strip prepared at the upstream side of the table.

We claim:

1. An apparatus for the application of binder strip to a fabric workpiece, comprising:

a sewing machine having a stitching site along a table and adapted to sew a binder strip onto a fabric workpiece at said site;

fabric-feed means shiftable along said table toward said site for advancing a fabric workpiece in the direction of said site from an upstream location; and

binder-feed means along said table for positioning a binder strip on said fabric workpiece as said fabric workpiece is fed to said site, said binder-feed means including at least two folding members alignable in said direction and independently operable to fold and guide the binder strip fed to said site, and respective elevated means for each of said members whereby the member proximal to said site may remain effective during the stitching of the binder strip to the fabric workpiece while the member distal from said site is elevated to enable the preparation of another fabric workpiece and binder strip therebelow.

2. The apparatus defined in claim 1 wherein said binder-feed means includes a clamp upstream from said proximal member and co-operating with said distal member for retaining a binder strip during operation of said distal member and thereafter delivering the retained binder strip to said distal member, said clamp being provided with a further elevating means operable independently of the elevating means of said proximal and distal members.

3. The apparatus defined in claim 2 wherein said clamp and said distal member are shifted by the respective elevating means at respective angles to said table and said proximal member is shifted by its elevating means perpendicularly to said table.

4. The apparatus defined in claim 3 wherein said proximal member has an end turned slightly upwardly and narrowing in the direction of said distal member for receiving a folded binder strip therefrom.

5. The apparatus defined in claim 4 wherein each of said members is of inverted-T profile, each of said elevating means is a fluid-responsive cylinder and said apparatus further comprises:

an upright mounted on said table; a horizontal shaft mounted vertically adjustably on said upright and overlying said table; and

respective brackets supporting each of said cylinders on said shaft with freedom of angular adjustment about the axis thereof.

6. The apparztus defined in claim 5 wherein said fabric-feed means comprises a pair of rails extending in parallel spaced-apart relationship in said direction and shiftable therealong from said location to said site beneath said clamp and along said members, said rails being spaced apart to receive said distal member and having respective folding plates shiftable toward each other for folding said binding strip about said distal member.

7. The apparatus defined in claim 6, further comprising a respective pneumatic cylinder on each of said rails, operatively connected with the respective folding plate for displacing same parallel to itself.

8. The apparatus defined in claim 7, further comprising guide means disposed on said table adjacent said sewing machine and including a pair of support rails and a linkage connecting said carriage with said spaced-apart rails of said fabric-feed means for displacing the latter along said table and raising and lowering said fabric-feed means.

9. The apparatus defined in claim 8, further comprising a threaded spindle extending parallel to said support rails and driving said carriage.

10. The apparatus defined in claim 9 wherein said sewing machine is a double-needle sewing machine provided with means for slitting said fabric workpiece between rows of stitches formed by the needles.

Claims

1. An apparatus for the application of binder strip to a fabric workpiece, comprising: a sewing machine having a stitching site along a table and adapted to sew a binder strip onto a fabric workpiece at said site; fabric-feed means shiftable along said table toward said site for advancing a fabric workpiece in the direction of said site from an upstream location; and binder-feed means along said table for positioning a binder strip on said fabric workpiece as said fabric workpiece is fed to said site, said binder-feed means including at least two folding members alignable in said direction and independently operable to fold and guide the binder strip fed to said site, and respective elevated means for each of said members whereby the member proximal to said site may remain effective during the stitching of the binder strip to the fabric workpiece while the member distal from said site is elevated to enable the preparation of another fabric workpiece and binder strip therebelow.

5. The apparatus defined in claim 4 wherein each of said members is of inverted-T profile, each of said elevating means is a fluid-responsive cylinder and said apparatus further comprises: an upright mounted on said table; a horizontal shaft mounted vertically adjustably on said upright and overlying said table; and respective brackets supporting each of said cylinders on said shaft with freedom of angular adjustment about the axis thereof.