US3799082A

US3799082A - Machine for simultaneously sewing the opposite edges of strip material

Info

Publication number: US3799082A
Application number: US00382854A
Authority: US
Inventors: H Redman
Original assignee: Mathewson Corp
Current assignee: Mathewson Corp
Priority date: 1973-07-26
Filing date: 1973-07-26
Publication date: 1974-03-26
Anticipated expiration: 1991-03-26

Abstract

Apparatus for sewing the opposite edges of strip material with one pass of the strip comprising a turn bar supported at 45* to the direction of delivery of the strip material thereto and at 45* to the direction of withdrawal of the strip material therefrom so that the portions of the strip travelling to and from the turn bar are at right angles to each other, a reel for giving up the strip material prior to sewing, a reel for taking up the sewn strip material following sewing, guides for guiding the strip material to and from the turn bar for inversion as it passes about the turn bar, sewing machines arranged to sew the opposite edges of the portions of the strip at the inner side of the right angle that the portions make with each other, and feed rolls for moving the strip material from the one reel to the other relative to the guides, sewing machines and turn bar.

Description

United States Patent Redman Mar. 26, 1974 [54] MACHINE FOR SIMULTANEOUSLY 3,339,506 9/1967 McGregor 112/10 SEWING THE OPPOSITE EDGES 0F STRIP MATERIAL Primary ExaminerAlfred R. Guest Attorney, Agent, or Firm-Dike, Bronstein, Roberts & [75] Inventor: Howard E. Redman, Duxbury, Cushman Mass.

[73] Assignee: Mathewson Corporation, Quincy, ABSTRACT Mass.

Apparatus for sewing the opposite edges of strip material with one pass of the strip comprising a turn bar supported at 45 to the direction of delivery of the strip material thereto and at 45 to the direction of withdrawal of the strip material therefrom so that the portions of the strip travelling to and from the turn bar are at right angles to each other, a reel for giving up the strip material prior to sewing, a reel for taking up the sewn strip material following sewing, guides for guiding the strip material to and from the turn bar for inversion as it passes about the turn bar, sewing machines arranged to sew the opposite edges of the portions of the strip at the inner side of the right angle that the portions make with each other, and feed rolls for moving the strip material from the one reel to the other relative to the guides, sewing machines and turn 31 Claims, 15 Drawing Figures [22] Filed: July 26, 1973 [21] Appl. No.: 382,854

[52] US. Cl. 112/3 R, 112/12l.15 [51] Int. Cl D05b ll/OO [58] Field of Search 112/3, 10, 138,63,121.11, l 1l2/l21.l4,l21.l5

[5 6] References Cited UNITED STATES PATENTS 1,243,679 10/1917 Allen l12/12l.1l

2,062,359 12/1936 Gail 112/3 R 2,318,686 5/1943 Hathaway...v ll2/l2l.14

2,667,132 1/1954 Golden l 1 112/70 bar 3,126,848 3/1964 Gastonguay 112/10 3,224,394 12/1965 Dobner et a1 ll2/121.15 X

11 58 +4 so 14 E I I l i 160 t" PAIENIEBIARZG m4 3; 799.082

SHEEI 2 BF 6 FIG.4

MACHINE FOR SIMULTANEOUSLY SEWING THE OPPOSITE EDGES OF STRIP MATERIAL BACKGROUND OF THE INVENTION It is customary when sewing strip material long two parallel edges to present one edge of the strip material to the sewing machine and sew the entire edge from end to end and then to turn the strip end for end and sew it along its opposite edge from end to end. This is time consuming hence efforts have been made to sew both of the edges at the same time by advancing the strip material between sewing instrumentalities located at opposite sides of the strip. Such machines have been generally unsatisfactory because it is quite difficult to advance both edges at the same rate especially if the material is dimensionally unstable. It is consequently the purpose of this invention to provide a machine for sewing along both edges without requiring that the edges be advanced at the same rate and further to provide a machine which is substantially automatic in its operation and can be easily adjusted for strip material of different widths.

SUMMARY As herein illustrated, the apparatus is for seaming the opposite edges of the side paneling employed in mattress manufacture and comprises a turn bar, means for delivering the paneling to one side of the turn bar in a direction at 45 thereto and withdrawing it from the opposite side in a direction at right angles to the direction of delivery to the turn bar such that portions of the paneling travelling to and from the turn bar and their edges are at right angles to each other and sewing instrumentalities supported along the edges of said portions at the inner side of the right angle that said portions make as they travel to and from the turn bar for sewing the edges at said inner side. The turn bar is supported on a table in a horizontal position and in spaced parallel relation thereto so that the means for delivering the paneling to the bar delivers it to the underside and the means for withdrawing it from the turn bar withdraws it from the upper side. There are guide means for conducting the paneling to and from the turn bar comprising spaced parallel guide elements arranged to have engagement with the opposite edges of the paneling and means for adjusting the spacing between the elements. The sewing instrumentalities comprise sewing machines mounted on the table with their feed tables at right angles to each other adjacent the edges of the paneling at the inner side of the angle of intersection of said edges and there are auxiliary supporting tables situated outwardly of the feed tables for supporting the paneling along the outer edges of the angle of intersection of the paneling. These latter auxiliary supporting tables are supported for movement from operative positions substantially at the level of the feed tables and the sewing machine to retracted positions. In their operative positions the table support the guide bars for adjustment heightwise and lengthwise thereof to control the level and lateral position of the paneling as it moves to and from the turn bar. There is also means for adjusting the turn bar along a line which is at 45 to the direction of travel of the paneling toward and away from the turn bar comprising a screw and crank.

The invention will now be described in greater detail with reference to the accompanying drawings wherein:

FIG. 1 is a plan view omitting, except for a fragmentary portion, the reel from which the material is delivered to the machine for sewing and the reel for taking up the material from the machine following sewing;

FIG. 2 is a transverse section through the panel material showing the edges which are sewn on the machine of this invention;

FIG. 3 is an elevation taken on the line 33 of FIG.

FIG. 4 is an elevation taken on the line 44 of FIG.

FIG. 5 is an elevation taken on the line 5-5 of FIG.

FIG. 5a is an elevation of the take-up reel and its stand;

FIG. 5b is an elevation taken at the left side of FIG. 5a;

FIG. 6 is an elevation with parts shown in section taken on the line 6-6 of FIG. 1;

FIG. 7 is an elevation, partly in section, taken on the line 77 of FIG. 1;

FIG. 8 is an elevation, partly in section, taken on the line 88 of FIG. 1;

FIG. 9 is an elevation taken in the direction of the arrow 9 of FIG. 8;

FIG. 10 is a horizontal section taken on the line l0-10 of FIG. 3;

FIG. 11 is an elevation taken on the line 11-11 of FIG. 1;

FIG. 12 is an elevation taken in the direction of the

arrows

12,12 of FIG. 11; and

FIG. 13 is an elevation similar to FIG. 1 1 showing the support displaced laterally.

In the manufacture of mattresses the top and bottom panels are joined by a side panel which extends continuously all the way around the mattress and is sewn at its top and bottom edges to the top and bottom panels. conventionally the side panel is comprised of natural or man-made fibers and is flammable. Government regulations require that mattresses be manufactured to Mattress Flammability Standards and it is now the practice to make the top and bottom panels and the side panels of two plies of woven fabric with, for example, a cellular polyurethane layer x between them (FIG. 2). Sandwiching the polyurethane layer between the woven material requires that the edges e-e of the woven material be sewn along the opposite edges of the layer at of polyurethane and this has been done by assembling the layers in superposed relation and then running the assembly through a sewing machine throughout its entire length to sew a seam along one edge and then turning it end for end and running it through the machine again throughout its entire length to sew the opposite edge. The present invention is for the purpose of providing a machine which will sew both edges with one pass of the entire length of the material through the machine.

The machine for accomplishing the foregoing comprises, in general, as shown in FIG. 1, a flat supporting table 10 mounted on a suitable base B in a horizontal position on which there is mounted a turn bar 12, guides 14-14 for directing the material to be sewn to the turn bar and directing it away from the turn bar, sewing machines 16-16, secondary supports l8-18 and feed means 20 for drawing the material through the machine. Reels R-1 and R2 are provided from which the material is delivered up to the turn bar and upon which it is wound following the sewing operation.

The reel R-l supplying the material is free-turning while the reel R-2 is power-driven by a motor M2 as illustrated in FIGS. 5a and 5b.

The turn bar 12, as shown in FIGS. 1 and 6, is mounted in a horizontal position above the table and in spaced parallel relation thereto, at the upper ends of a pair of spaced parallel, vertically disposed arms 22-22 joined by a cross-bar 24 which is fastened by a bolt 32 to a part 28 which extends upwardly through a slot 30 from a bracket 26 at the underside of the table. The bracket contains at its underside a channel 34 in which there is mounted on gimbals 36-36 a nut 38. A screw 39 supported in a bearing plate 40 at the edge of the table and retained against axial movement by a collar 42 fixed to it at the inner side of the bearing plate and the hub 44 of a crank fixed to it at the outer side of the bearing plate is threaded through the nut. Rotation of the crank 46 and hence the screw will thus move the turn bar in a direction perpendicular to its axis which, as shown in FIG. 1, is disposed at an angle of 45 to the direction from which the material is delivered to it and from the direction from which the material is drawn away from it.

The paneling is guided from the reel R at the left (FIG. 1) on which it is supported in a direction at 45 to the axis of the turn bar by the guide means 14 and is drawn away from the turn bar at a corresponding angle by the guide means 14 at the right which is identical with that by means of which the paneling is delivered to the turn bar. Each guide means 14 comprises, as shown in FIGS. 4 and 5, spaced

parallel rods

48 and 50 mounted between plates 5252 provided with hubs 54-54 and threaded stub shafts 56-56 which support them at the upper ends of spaced parallel posts 58-58, the lower ends of which are fastened to the table 10. A pair of end guide plates 60-60 are slidingly mounted on the

rods

48, 50 for movement along these rods to provide a spacing therebetween which corresponds to the width of the paneling which is being sewn in order to have engagement with the opposite edges, to guide the paneling to the turn bar and also to control its lateral position so that the edges to be sewn will be in registration with the sewing instrumentalities. Set screws 62-62 screwed into openings in the end plates 60-60 against the rod 50 provide for fixing the end guide plates following adjustment for paneling ofa predetermined width.

The paneling is moved through the guide means and about the turn bar in the direction of the arrows shown in FIG. 1 by the feed means which comprises, as shown in FIGS. 1, 8 and 9, a pair of

feed rolls

64 and 66 supported for rotation in engagement with each other between spaced parallel, vertically disposed bracket plates 67-67 with the bite between the rolls substantially at the level of the axis of the turn bar. The

rolls

64 and 66 are mounted on spaced

parallel shafts

68 and 70. The shaft 68 is rotatably supported at its opposite ends in bearing assemblies 72-72 bolted to the bracket members 67-67. The feed roll 64 is secured to the shaft 68 for rotation therwith by a key 74 and rotation of the shaft 68 is effected by a sprocket 76 fastened to one end. A chain 78 is entrained at one end about the sprocket 76 and at its other end about a sprocket 80, fixed to a shaft 81 on which is mounted the reel R-2. The shaft 81 is chain driven by a motor M2 (FIGS. 5a and 5b). The shaft is supported between the bracket plates 67-67 on pivots 88-88 between lever arms 90-90 which, in turn, are pivotally supported at 92-92 on the bracket members. By rocking the arms 90-90 outwardly with respect to the ends of the shaft 70, the latter may be raised relative to the shaft 68 to separate the roll 66 from the roll 64. This facilitates threading the machine. The arms 90-90 are spring-biased inwardly with respect to the ends of the shaft by coiled springs 94-94 mounted on toggle spindles 96-96 in compression between shoulders 98 and 100. The

rolls

64 and 66 have bolted to one end gears 102 and 104 which mesh when the rolls are held engaged so that the lower roll 64 which is driven, as described above, effects rotation of the upper roll 66.

The sewing instrumentalities 16-16 which comprise sewing machines are mounted on the table 10 adjacent the path of travel of the inner edges of the paneling symmetrically with respect to a line drawn perpendicualr to the axis of the turn bar midway between its ends in positions such that the feed tables 103-103 of the two sewing machines are disposed at right angles to each other, the one parallel to the direction of movement of the paneling toward the turn bar and the other parallel to the direction of movement of the paneling away from the turn bar. As thus arranged one edge of the paneling as it travels toward the feed bar, that is, the near edge, as illustrated in FIG. 1, is sewn by the sewing machine at the left of the apparatus and the 0pposite edge is sewn as it leaves the turn bar by the sewing machine at the right of the apparatus. The sewing machines are driven by conventional means, here shown as belts 106 (FIG. 3), entrained at one end about pulleys 108 on the machines and at their opposite ends about pulleys 110 on shafts at the underside of the table driven by a motor M.

Since the paneling is supported only along edge as it passes over the feed tables 103-103 and if not otherwise supported would sag at its opposite edge additional supporting means 18-18 is provided opposite the feed tables which can be moved into and out of operative position. Each supporting means 18 as illustrated in FIGS. 11, 12 and 13 comprises a flat plate 122 of substantially rectangular configuration hingedly connected to the upper ends of pairs of spaced parallel legs 124-124, the lower ends of which are hingedly connected to a base plate 126 fastened by a bolt 128 to the table 10. A coiled spring 130 secured at its opposite ends diagonally of the pairs of legs 124-124 to a lug 132 at one end and to a cross-bar 134 at the other end which rests on shoulders 136-136 mounted on the legs 124-124 supports the legs in upright positions with the plate 122 in a horizontal position substantially at the level of the feed table. A hold-down bar 138 is mounted on the plate 122 in spaced parallel relation thereto on an angle bracket member 140 having an upright part 142 containing slots 144-144 for receiving thumb screws 146-146 by means of which the bar 138 is adjustably mounted for heightwise adjustment and a part 148 having spaced parallel channels 150-150 slidably engaged with the edges of the plate 122 by means of which it may be adjusted along the plate 122 toward and from the feed table of the sewing machine. A thumb screw 152 provides for fixing the bar in a predetermined position such that the part 142 coincides with the outer edge of the paneling and functions together with the guide 14 to control the movement of the paneling toward and from the turn bar.

The pulleys 110-110 which transmit power to the sewing machines, as shown in FIG. 10, are fixed to shafts 154a, l54b journaled at right angles to each other in the base B and interconnected by beveled gears 158a, l58b so that rotation of one of the shafts effects rotation of the other. The shaft l54b is driven by a pulley 155 and belt 157 from the motor M.

The reels R-l, R-2, as shown in FIGS. 5a, 5b, are rotatably mounted on stands 160 and the stand which mounts the reel R-2 has mounted on it a motor M2 for driving the shaft 85 on which the reel R-2 is mounted to wind the material onto the reel as it is delivered thereto by the feed rolls.

Conventional thread-break controls are provided on the sewing machine for stopping the feed rolls in the event of thread breakage. For example, microswitches and switch arms held in operative position by the running thread are released by breakage of the thread to actuate the switches.

Each of the sewing machines is a Union Special, although it is to be understood that other commercially available sewing machines may be used and is provided with a conventional trimmer so that the edges of the material being sewn may be simultaneously trimmed to provide a uniformly wide margin outboard of the machine. In the drawings since the trimming mechanism is conventional it is indicated at t without further elaboration or description.

The machine as thus described provides for sewing and simultaneously trimming along both edges of the side paneling used in the manufacture of mattresses simultaneously with one pass of the paneling through the machine thus materially reducing the work time required for the operation that it halves the handling time and at the same time automates the operation in that the operator is not required to manually guide or manipulate the material during the seaming operation. It is to'be understood that while the apparatus was designed especially for seaming the side paneling for mattresses it can be used equally well for seaming the opposite edges of any assembly of several layers of material at opposite sides with one pass of the material through the machine.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents falling within the scope of the appended claims.

I claim:

1. Apparatus for seaming the opposite edges of side paneling employed in mattress manufacture, comprising a turn bar, means for delivering the paneling to one side of the turn bar in a direction of 45 thereto and withdrawing it from the opposite side in a direction at right angles to the direction of delivery to the turn bar such that portions of the paneling travelling to and from the turn bar and their edges are at right angles to each other, and sewing instrumentalities supported along the edges of said portions at the inner side of the right angle that said portions make as they travel to and from the turn bar for sewing the edges at said inner side.

2. Apparatus according to claim 1, comprising means mounting the turn bar in a horizontal position wherein the means for delivering the paneling to the bar delivers it to the underside thereof and the means for withdrawing the paneling from the bar withdraws it from the upper side thereof.

3. Apparatus for seaming the opposite edges of side paneling employed in mattress manufacture, comprising a turn bar, means for delivering the paneling material to the turn bar along a predetermined path at 45 to the axis of said turn bar and withdrawing it from the turn bar along a predetermined path at 45 to the axis of the turn bar such that portions of the paneling travelling to and from the turn bar and their edges are disposed at right angles to each other, and sewing instrumentalities mounted adjacent the path of movement of the edges of said portions at the inner side of the angle that said portions make with each other.

4. Apparatus for seaming the opposite edges of side paneling employed in mattress manufacture, comprising a support, a turn bar mounted on the support, means for giving up strip material to the turn bar and taking it away from the turn bar in directions at right angles to each other with the edges of the portions travelling away from the turn bar reversed with respect to the edges travelling toward the turn bar, guide means for delivering the strip given up to the turn bar along a line at 45 to the axis of the turn bar, guide means for conducting the strip away from the turn bar to the take-up along a line at 45 to the turn bar, and means mounted adjacent the respective edges of the portions of the strip travelling to and from the turn bar at the inner side of the right angle said portions make with each other for sewing said edges.

5. Apparatus according to claim 4, comprising means for adjusting the turn bar relative to the guide means in a horizontal plane and in a direction perpendicular to its axis.

6. Apparatus according to claim 4, wherein the guide means has spaced guide elements for guiding the opposite edges of the strip, comprising means for adjusting the spacing of the guide elements for different widths of the strip.

7. Apparatus according to claim 4, comprising a support associated with each sewing means for supporting the travelling strip between the guide means and the turn bar at the place of sewing.

8. Apparatus according to claim 4, wherein each sewing means is provided with a feed table supported adjacent the path of travel of the strip, said feed tables being disposed at right angles to each other and providing support for the edges of the strip at the inner side of the right angle as they are sewn, and an outboard support mounted opposite each feed table at the level thereof for supporting the portions of the strip outwardly of said feed tables.

9. Apparatus according to claim 8, wherein a holddown element is mounted on each outboard support above and in spaced parallel relation thereto at a spacing such as to permit the strip to travel between it and the outboard support.

10. Apparatus according to claim 8, comprising means for supporting the outboard support for movement to a retracted lateral position.

11. Apparatus according to claim 8, comprising legs pivotally connected at one end to said support and at their other ends to said outboard support, and springs yieldably urging the legs to upright positions.

12. Apparatus for seaming the opposite edges of strip material comprising a table, two guides, each having spaced parallel guide elements disposed on the table with the parallel sides of one at right angles to the parallel sides of the other so that center lines drawn parallel to said elements midway between them intersect at right angles, a turn bar, means mounting the turn bar on the table with its axis at the point of intersection of said line and at 45 to each line, two sewing instrumentalities mounted on the table at the inner side of said right angle of intersection of said center lines on lines parallel to said center lines, and means for adjusting the position of the turn bar relative to said sewing instrumentalities along a line bisecting said right angle.

13. Apparatus according to claim 12, wherein the means for adjusting the turn bar comprises a screw journaled on the table for rotation about its longitudinal axis, a nut on the screw, means connecting the nut to the turn bar and a crank for rotating the screw.

14. Apparatus according to claim 12, wherein the table contains a slot and the means for adjusting the turn bar on the table comprises a block at the underside of the table embodying a part extending upwardly through the slot, a bracket at the upper side of the table bolted to said part, said bracket supporting the turn bar spaced from and parallel to the table, a nut mounted on the block, a screw threaded through the nut, a journal on the table supporting the screw for rotation and for preventing axial movement thereof and a handle for rotating the screw.

15. Apparatus according to claim 12, wherein each guide comprises a rod supported above the table in spaced parallel relation thereto on which the guide elements are slidingly mounted for movement along the rod and there are means for fixing the guide elements at predetermined positions on the rod.

16. Apparatus according to claim 12, wherein each guide comprises a pair of spaced parallel rods supported above the table in spaced parallel relation thereto on which the guide elements are slidingly mounted, each guide element comprising a disc containing spaced holes radially of its center for sliding engagement with the rods and having a flatside surface such that the side surfaces of the discs are parallel and perpendicular to the axes of the rods, and means for fixing the discs at predetermined distances apart on said rods.

17. Apparatus according to claim 12, wherein a first reel provides support for a coil of the strip for unwinding as it is delivered to the turn bar and a second reel provides for rewinding the sewn strip which is drawn from the turn bar to form a coil.

18. Apparatus according to claim 17, comprising means for rotating the second reel to wind the sewn strip onto it.

19. Apparatus according to claim 17, comprising stands for supporting first and second reels, shafts mounted on the stands for receiving the reels, and a motor on the stand on which the second reel is mounted for effecting rotation of said second reel.

20. Apparatus according to claim 12, comprising means for moving the strip relative to the sewing means comprising traction rolls located beyond the second sewing means in the direction of travel between which the strip is moved by rotation of the rolls.

21. Apparatus according to claim 20, comprising means for supporting the traction rolls on spaced parallel shafts, with one shaft fixed and the other movable relative to the fixed shaft to enable separating the rolls.

22. Apparatus according to claim 21, comprising lever arms supporting the movable shaft for movement relative to the fixed shaft and comprising toggle means for biasing the lever arms to positions to support the movable rolls in cooperative engagement with the fixed roll.

23. Apparatus according to claim 12, wherein each sewing instrumentality has a sewing table parallel to the support table situated at the level of the turn bar.

24. Apparatus according to claim 23, comprising an outboard table mounted on the support table outwardly of each sewing table and substantially at the level thereof.

25. Apparatus according to claim 24, comprising a guide bar mounted on each outboard table in spaced parallel relation thereto.

26. Apparatus according to claim 25, comprising means for adjusting the guide bar heightwise relative to the outboard table.

27. Apparatus according to claim 25, comprising means for adjusting the guide bar along said auxiliary table toward and from the sewing instrumentality.

28. Apparatus according to claim 24, comprising legs pivotally supporting each outboard table for movement away from the sewing instrumentality to an out of the way position.

29. Apparatus according to claim 28, comprising spring means yieldably supporting the legs upright.

30. Apparatus according to claim 1, comprising means for simultaneously trimming the edges of the material to uniform width outboard of the seams.

31. Apparatus according to claim 1, comprising cutters associated with the respective sewing instrumentalities operable in consonance therewith to simultaneously trim the edges of the material as they are sewn to provide a uniformly wide margin along each edge outboard of the seam.

Claims

1. Apparatus for seaming the opposite edges of side paneling employed in mattress manufacture, comprising a turn bar, means for delivering the paneling to one side of the turn bar in a direction of 45* thereto and withdrawing it from the opposite side in a direction at right angles to the direction of delivery to the turn bar such that portions of the paneling travelling to and from the turn bar and their edges are at right angles to each other, and sewing instrumentalities supported along the edges of said portions at the inner side of the right angle that said portions make as they travel to and from the turn bar for sewing the edges at said inner side.

3. Apparatus for seaming the opposite edges of side paneling employed in mattress manufacture, comprising a turn bar, means for delivering the paneling material to the turn bar along a predetermined path at 45* to the axis of said turn bar and withdrawing it from the turn bar along a predetermined path at 45* to the axis of the turn bar such that portions of the paneling travelling to and from the turn bar and their edges are disposed at right angles to each other, and sewing instrumentalities mounted adjacent the path of movement of the edges of said portions at the inner side of the angle that said portions make with each other.

4. Apparatus for seaming the opposite edges of side paneling employed in mattress manufacture, comprising a support, a turn bar mounted on the support, means for giving up strip material to the turn bar and taking it away from the turn bar in directions at right angles to each other with the edges of the portions travelling away from the turn bar reversed with respect to the edges travelling toward the turn bar, guide means for delivering the strip given up to the turn bar along a line at 45* to the axis of the turn bar, guide means for conducting the strip away from the turn bar to the take-up along a line at 45* to the turn bar, and means mounted adjacEnt the respective edges of the portions of the strip travelling to and from the turn bar at the inner side of the right angle said portions make with each other for sewing said edges.

9. Apparatus according to claim 8, wherein a hold-down element is mounted on each outboard support above and in spaced parallel relation thereto at a spacing such as to permit the strip to travel between it and the outboard support.

12. Apparatus for seaming the opposite edges of strip material comprising a table, two guides, each having spaced parallel guide elements disposed on the table with the parallel sides of one at right angles to the parallel sides of the other so that center lines drawn parallel to said elements midway between them intersect at right angles, a turn bar, means mounting the turn bar on the table with its axis at the point of intersection of said line and at 45* to each line, two sewing instrumentalities mounted on the table at the inner side of said right angle of intersection of said center lines on lines parallel to said center lines, and means for adjusting the position of the turn bar relative to said sewing instrumentalities along a line bisecting said right angle.