EP0016437B1

EP0016437B1 - Automatic seaming method and apparatus for gored panty-hoses

Info

Publication number: EP0016437B1
Application number: EP19800101352
Authority: EP
Inventors: Rikichi Senba
Original assignee: TAKATORI MACHINERY WORKS Ltd
Current assignee: TAKATORI MACHINERY WORKS Ltd
Priority date: 1979-03-16
Filing date: 1980-03-14
Publication date: 1984-06-27
Also published as: EP0016437A1; AU5651780A; CA1161308A; DE3068340D1

Description

The invention relates to an automatic seaming method and apparatus for gored panty-hoses according to claims 1 and 10, respectively.
One conventional method for producing a gored panty-hose includes in general two- staged seaming operations. In the first stage, two leg sections and a panty section are seamed together by the so-called skip seaming whilst leaving an unseamed opening in the crotch of an incomplete panty-hose. Next in the second stage, a separate gore piece is fitted to the unseamed opening and its marginal edge is seamed to the marginal portion of the unseamed opening in order to form a complete panty-hose.
Due to the complicated form of the seaming line for attaching of the gore piece to the opening, the seaming operation is extremely complicated and difficult to practice successfully. For this reason, the seaming of the gore piece according to this method has conventionally depended upon manual operation by expert operators. This naturally causes low productivity of the second stage seaming operation, increased human labour and resultant high increase in the production cost of gored panty-hoses as well as variations in quality from product to product.
In order to avoid this disadvantage, a number of automatic seaming methods for gored panty-hoses have been proposed. Due to the unavoidable presence of the above-described complicated seaming line, however, one cannot expect reliable operations of the apparatuses for practicing such automatic seaming methods. In order to obtain high reliability in operation, one needs to adopt an extremely complicated design for such an apparatus. Thus, none of the known methods and apparatus have been able to carry out the second stage automatic seaming operation with appreciably satisfactory results.
According to a method and an apparatus known from GB-A-2 001 238 an incomplete panty-hose is turned inside out and pulled over a tube assembly comprising two tubes one being located within the other. A gore piece is presented to the protruding front end of the outer tube and held in position by pneumatic suction. The gore piece then is drawn into the crotch opening of the incomplete panty-hose to form a substantially cupped shape. Then the tubes are moved to bring one part of a cup seaming machine, either its needle bar or its needle plate, into the cupped shape gore piece and the marginal portion of the unseamed opening surrounding it. The tube assembly with the panty-hose and the gore piece are rotated about the tube axis through at least 360° while an overlocking seaming machine is running to seam the gore piece to the opening.
Another method is described in a European Patent Application 80 850 018.5.
The object of the invention is to provide an automatic seaming method for seaming a gore piece to the unseamed opening of the incomplete panty-hose at remarkably high production efficiency, with low production cost and extremely small variance in quality, on an automatic apparatus which is of a simple construction and is capable of carrying out the above-described second stage seaming operation with high reliability in operation.
The above-mentioned object is achieved according to the invention by the characterizing parts of the claims 1 and 10, respectively.

Brief description of the drawings

Fig. 1 is a perspective view of an incomplete panty-hose having an opening in the crotch,
Fig. 2 is a perspective view of a complete panty-hose with a gore piece seamed to the opening,
Fig. 3 is a perspective view, partly removed for easy understanding, of one embodiment of a seaming apparatus in accordance with the invention,
Fig. 4 is a plan view of the seaming apparatus shown in Fig. 3,
Fig. 5 is a side view, partly in section, of the suction assemblies and their related parts used for the seaming apparatus shown in Fig. 3,
Fig. 6 is a section taken along a line X-X in Fig. 5,
Fig. 7 is a side view, partly in section, of the transfer assembly and its related parts used for the seaming apparatus shown in Fig. 3,
Fig. 8 is a side view, partly in section, of the seaming machine and its related parts used for the seaming apparatus shown in Fig. 3,
Fig. 9A through 9D are perspective views for showing the sequential operational steps of the seaming method in accordance with the present invention,
Fig. 9E is a plan view of a panty section of the panty-hose which is produced by the seaming method of the present invention,
Fig. 10 and 11 are top and side views of a modified embodiment of the transfer assembly shown in Fig. 7, and
Figs. 12 and 13 are plan and side views of the heat cutting assembly used in the seaming assembly shown in Fig. 3.

Detailed description of the drawings

One typical example of a method for producing a gored panty-hose will hereinafter be explained briefly in reference to Figs. 1 and 2. The method includes dual staged seaming operations. A pair of cylindrical stocking materials 1 and 2, each closed at the toe end, of same size are superposed in the section forming the panty section 6 and cutting the stockings at the open end along a length corresponding to the panty section to produce front and rear cut edge portions 3, 4, respectively. Next a first seaming operation is performed on the stocking materials in order to obtain an incomplete panty-hose 7a such as shown in Fig. 1. The front and rear cut edge portions 3 and 4 are seamed together along seam lines 3a and 4a whilst leaving a cut edge 5 in the crotch of the panty section unseamed. The incomplete panty-hose thus includes an unseamed opening 5a in the crotch.
This sort of so-called skip seaming operation can easily be carried out on a known line close such as the one disclosed in Japanese Patent 880,791.
In the second stage seaming operation, a gore piece 10, Fig. 9C, is fitted to the above-described unseamed opening 5a in the incomplete panty-hose 7a, and the cut edge 5 in the crotch and the marginal edge of the gore piece 10 are seamed together along a seaming line 8 in order to form a complete gored panty-hose such as shown in Fig. 2.
One embodiment of the seaming apparatus in accordance with the present invention is shown in Figs. 3 and 4.
An operation table 102 is mounted atop a pedestal casing 101 and both are made up of semi-circular sections and integral square sections. An upwardly extending vertical shaft 103 is rotatably arranged about the center of the semi-circular section of the operation table 102 and a carrier disc 104 is horizontally mounted atop the main shaft 103. As shown in Fig. 3, four sets of downwardly extending suction assemblies 201 are disposed on the carrier disc 104 at equal intervals along its periphery. The number of the suction assemblies 201 is not limited to four sets and can be chosen as desired in accordance with requirement in practice. The suction assemblies 201 revolve, together with the carrier disc 104, about the axis of the main shaft 103 in the counterclockwise direction in the illustration in order to travel from the first to fourth operation stations I and IV provided on the operation table 102.
In the first station I, the incomplete panty-hose 7a having the unseamed opening 5a (see Fig. 1) is manually attached to one suction assembly 201 in that station. The leg sections are pneumatically sucked into the suction tube 203 while the marginal portion of cut edge 5 is folded over the outer surface of the lower end of the suction tube 203. Then the pneumatic suction acting on the suction assembly 201 is intercepted by suitable manual switching. As later described in more detail, hooks arranged in the suction tube 203 hold the sucked incomplete panty-hose within the suction tube 203 even after the temporary pneumatic suction is terminated.
In the second station II, a gore piece 10 cut into a prescribed shape is passed to a gore piece transfer assembly 401 by a gore piece feeder assembly 301.
Concurrently with the transfer of the gore piece 10, an adequate number of cuts are formed in the marginal portion of the cut edge 5 folded over the outer surface of the lower end of the suction tube 203 by a heat cutting assembly 501. The cuts extend from the cut edge inwardly of the marginal portion. The transfer assembly 401 fits, by its own rotation, the gore piece 10 in the correct position to the incomplete panty-hose 7a held by the suction assembly 201 and the marginal portion of the opening 5a is unfolded by e.g., application of pneumatic blow, in order to be superimposed upon the marginal edge of the gore piece 10 already placed in position on the second station II.
In the third station III, the suction assembly 201 revolves together with the incomplete panty-hose 7a and the gore piece 10 so that a sewing machine 601 seams the cut edge 5 in the crotch of the incomplete panty-hose 7a with the marginal portion of the gore piece 10 in order to obtain a complete panty-hose 7.
In the fourth station IV, the complete panty-hose 7 is removed off the suction assembly 201 to be discharged outside the systems by a removing assembly 701.
Detailed constructions of the above-described various assemblies are as follows.

(1) The carrier disc 104

As shown in Figs. 3 and 5, the main shaft 103 is rotatably carried, via thrust bearings 106 and 107, by a cylindrical stand 105 fixed atop the operation table 102. The main shaft 103 is cylindrical in shape and its lower end is connected to an adequate suction source 108a by a suction pipe 108. The pneumatic suction is controlled by ordinary switching operation.
A drive motor 109 accompanying a known reduction gear mechanism is arranged under the operation table 102 and its output shaft carries a drive pulley 1 lOa which is operationally coupled, via a drive belt 111, to a driven pulley 11 Ob mounted to the main shaft 103. By properly controlling the operation of the drive motor 109, the main shaft 103 and the carrier disc 104 are driven for intermittent rotation, each movement covering an angle of 90 degrees.
As a substitute for the above-described arrangement for the intermittent rotation, any known drive mechanism such as a Geneva Index unit may be used. Further, a known timer or the like may be used for control of the drive motor 109.

(2) The suction assembly 201

As shown in Figs. 3 and 5, each suction assembly 201 includes a vertical suction tube 203 which is rotatably carried at its top by a boss 104a on the carrier disc 104 by means of thrust bearings 202. The suction tube 203 is open at both longitudinal ends and a skirt- shaped bottom flange 205 is fixedly inserted over its bottom end. At a level near the top end, a gear 204 is fixedly inserted over the suction tube 203 for engagement with a later described suction tube driver assembly 50.
At least one hook 206 is fixed at its lower end to the inside wall of the suction tube 203, which is made of a flexible material such as a synthetic resin. The hook 206 blocks falling of the incomplete panty-hose 7a outside the suction tube 203 when the pneumatic suction is intercepted at the first station I. Preferably, three or more hooks 206 are arranged in the suction tube 203 for reliably holding of the incomplete panty-hose 7a within the suction tube 203.
A cover disc 120 is mounted above the carrier disc 104. It is rotatably supported at the top end of the main shaft 103 via a thrust bearing 121. The diameter of the cover disc 120 is almost equal to that of the carrier disc 104. As later described in more detail, the cover disc 120 is coupled to the pedestal casing 101 by means of the removing assembly 701 and, consequently, held stationarily despite the rotation of the main shaft 103.
As shown in Fig 6, circular holes 122 and 123 are formed in the cover disc 120 at positions corresponding to the first and fourth stations I and IV. The positions of these holes 122 and 123 are selected so that they correctly meet the top opening of a suction tube 203 when the latter is in these stations I and IV.
A perforated block disc 124 is arranged in the circular hole 122 in the first station I in an arrangement flush with the bottom face of the cover disc 120. The circular hole 122 is connected to the top opening of the main shaft 103 by means of a curved pipe 126. Thus, pneumatic suction acts on the suction tube 203 via the cylindrical main shaft 103, the curved pipe 126 and the perforated block disc 124.

(3) The suction tube driver assembly 50

As shown in Figs. 3 and 5, a drive motor 53 is fixed, by means of a bracket 51, to the cover disc 120 at a position corresponding to the third station III. A gear 55 fixed to its output shaft is engageable with the gear 204 on the suction tube 203 when the latter is at the third station III. As the drive motor 53 is activated, the suction tube 203 starts to rotate about its own axis.

(4) The gore piece feeder assembly 301 and the gore piece transfer assembly 401

The detailed constructions of the assemblies are shown in Figs. 3,4 and 7.
In the second station II, a gore piece 10 cut into a prescribed shape is fed by the feeder assembly 301 to the transfer assembly 401 which in turn fits the gore piece 10 in the correct position to the incomplete panty-hose 7a held by the suction assembly 201 so that the sliced fringe 5 and the fringe of the gore piece are superimposed in a horizontal state.
As shown in Figs. 3 and 4, the feeder assembly 301 includes a feed reel 303 of the gore piece band which is conveyed towards the transfer assembly 401 by means of feed rollers 306 and 307 via guide and dancer rollers 304 and 305.
A supporting stand 310 is arranged on the square section of the operation table 102 and bears a drive motor 311 which is operationally coupled to the reel 303 and the rollers 304, 306 and 307 by means of ordinary pulleys and a drive belt. Upon each intermittent rotation of the drive motor 311, the gore piece band is delivered from the reel 303 by a length corresponding to one gore piece 10. A pair of vertically shiftable cutters 312 and 313 are arranged at a position between the rollers 306 and 307 in order to cut out the side fringes of the gore piece band in a triangular shape during the dwell of the intermittent delivery of the band. Concurrently with this procedure, a cutter 314 arranged on the stand 310 in front of the feed roller 307 shifts downwards and forms a cut in the band in order to form a gore piece 10 of a prescribed shape, e.g. a diamond shape.
The construction of the gore piece transfer assembly 401 will hereinafter be explained in more detail with reference to Figs. 4, 7 and 9C. A cylindrical bracket 403 is fixed at a prescribed position on the operation table 102 and rotatably carries a drum assembly 404.
The drum assembly 404 includes a cylindrical support shaft 405 having a lower section rotatably inserted into the bracket 403, and a pair of hollow support arms 406 extending horizontally and in opposite directions from the support shaft 405 at a level above the operation table 102. Each support arm 406 carries at its outer end a cylindrical upright shaft 407 having a top flange. A horizontal semi-circular plate 408 is located on the top flange of each upright shaft 407. The pair of semi-circular plates 408 faces each other along their straight edges whilst leaving a slight gap. Each semi-circular plate 408 is provided with numerous suction holes 408a formed therethrough.
An inner cylinder 411 of a double drum 410 is inserted over each upright shaft 407 and a compression spring 414 is imposed between the bottom wall of its outer cylinder 412 and the top flange of the upright shaft 407. The compression spring 414 co-axially surrounds the upright shaft 407. That is, the double drum 410 is elastically pressed towards the associated support arm 406. A flange 413 is formed atop the outer cylinder 412 and fixedly carries the associated semi-circular plate 408.
In the second station, a pneumatic cylinder 415 is fixed to the lower face of the operation table 102 and its piston rod 415a extends upwards slidably through the operation table 102 in order to face the lower face of the double drum 410. Consequently, as the piston rod 415a is driven for upward movement by the pneumatic cylinder 415, the double drum 410 is forced to move upwards over a prescribed distance whilst overcoming repulsion of the compression spring 414. The lifted position of the double drum 410 is shown with chain lines in Fig. 7.
Relationship in position between the pair of double drums 410 in the second station II is shown in Fig. 7. That is, the right side double drum 410 faces the downstream terminal of the gore piece feeder assembly 301 in order to receive a gore piece on its semi-circular plate from the feeder assembly. The left side double drum in the second.station II is located in axial alignment with the suction tube 203 of the suction assembly 201 in that station. In this state, a slight gap is left between the semi-circular plate 408 and the lower end of the bottom flange 205 on the suction tube 203.
At a level below the cylindrical bracket 403, a pulley 420 is fixedly inserted over the support shaft 405 and operationally coupled to a pulley 421 on the main shaft 103 (see Fig. 3) by means of a drive belt 422. As the main shaft 103 is driven for rotation by the drive motor 109, the drum assembly 404 with the double drums 410 rotates about the axis of the support shaft 405 in a direction shown by an arrow in Fig. 4, i.e. counterclockwise. The ratio in diameter between the two pulleys 420 and 421 is designed 1:2 so that the drum assembly 404 completes a 180 degrees rotation upon 90 degrees rotation of the main shaft 103.
As the main shaft 103 rotates over 90 degrees, each suction assembly 201 travels from a station to an adjacent station and the pair of double drums 410 alternate in position in order to rest in the new positions. During the dwell, a gore piece 10 is passed to the right side double drum 410 by the feeder assembly 301 whereas the left side double drum 410 assigns a gore piece to the suction assembly 201 in second station II.
The lower end of the support shaft 405 is coupled in an air-tight manner to a connection pipe 425 which is in turn connected to the suction pipe 108 (see Fig. 5) via a valve 426. The valve 426 takes the form of a normally closed valve which is made open only when the drum assembly 404 performs the 180 degrees rotation. This opening of the valve 426 allows application of pneumatic suction to the gore piece 10 on the associated semi-circular plate 408 via the connection pipe 425, the support arm 405, the support arm 407, a slit 407a in the upright shaft 407, the double drum 410 and the suction holes 408a of the semi-circular plate 408, thereby effectively blocking accidental falling of the gore piece during movement of the associated drum assembly 404.
As shown in Fig. 3, a flat guide plate 423 extends between the second and third stations I! and III along the travelling path of the suction assemblies 201. The top face of this guide plate 423 is flush with those of the semi-circular plate 408 in the lifted position (see Fig. 7) and the sewing table in the third station III. As the suction assembly 201 travels from the second to the third station with the gore piece 10 passed by the feeder assembly 401, the gore piece 10 slides on and along the guide plate 423. Therefore, the top face of the guide plate 423 should preferably be as smooth as possible. When necessary, any smoothing finish may be applied to its top face.

(5) Heat cutting assembly 501

Concurrently with transfer of the gore piece at the second station II, cuts are formed in the marginal portion of the cut edge 5 folded over the suction tube bottom flange 205 by heat cutting. In advance to the subsequent seaming on the sewing machine 601, the marginal edge portion of the opening 5a has to be unfolded, for example, by air blast in order to be superimposed on the fringe of the gore piece 10 located on the sewing table. Presence of the above-described cuts enables easy and successful flattening of the marginal portion of the cut edge 5. It is not always necessary to complete this flattening in the third station III. After the heat cutting is complete, the pneumatic flattening may also be carried out in the second station II. It is only required that the marginal portion of the cut edge 5 should be horizontally superimposed upon the marginal edge of the gore piece in advance to the seaming operation at the third station III.
The heat cutting assembly 501 will now be explained in more detail whilst referring to Figs. 3, 4, 12 and 13.
At a position adjacent the second station II, a bracket 503 is fixed to the operation table 102 and carries a pneumatic cylinder 505. A rack 507 is fixed at its one longitudinal end to the outer end of a piston rod 505a of the cylinder 505. An arm 509 is fixed to the other end of the rack 507 and carries an electrically heated cutter 511. The rack 507 is in engagement with a pinion 513 which in turn engages with a gear 519 on the opposite side of the rack 507. An arm 515 extends from the pinion 513 in a direction substantially normal to the longitudinal direction of the rack 507. Likewise, an arm 521 extends from the gear 519 in alignment with the arm 515. The arms 515 and 521 carry electrically heated cutters 517 and 523 at their free ends.
The arms and the cutters assume the inoperative position shown with solid lines in Figs. 12 and 13 when the pneumatic cylinder 505 is inoperative. As the cylinder 505 operates, the piston rod 505a projects and the heat cutter 511 with the arm 509 moves towards the suction assembly 201 in the second station II. and arrives at the operative position shown with chain lines. Concurrently, arms 515 and 521 also swing towards the suction assembly 201 with their heated cutters 517 and 523 in order to arrive at the operative positions shown with chain lines. At the operative positions, the heated cutters 511, 517 and 523 touch the cut edge 5 on the suction tube bottom flange 205 in order to form cuts at about 120 degrees intervals. As the piston rod 505a recedes into the pneumatic cylinder 505, arms and heat cutters all resume the inoperative positions. The number of the heated cutters, i.e. the number of cuts formed in the sliced fringe, is not limited to three. However, in consideration of simplicity in construction and easiness in flattening operation, it is advantageous to use three sets of heated cutters.

(6) A sliced fringe direction adjuster assembly 800

As described already, the transfer assembly 401 receive a gore piece from the feeder assembly in order to transfer it to the suction assembly 201 located at second station II so that the marginal portion of the cut edge 5 of the incomplete panty-hose 7a is superimposed upon the marginal edge of the gore piece 10. For correct seaming on the sewing machine 601, the seaming line on the gore piece 10 should meet that on the marginal portion of the cut edge 5 without any bias. In general in a gore piece 10 made of cotton or the like, stretch is larger in the warp direction than in the weft direction. Therefore, it is advantageous that the warp direction in the gore piece 10 should meet that of the seaming line in the marginal portion of the cut edge 5.
This adjustment is carried out by the direction adjuster assembly 800 shown in Figs. 10 and 11.
A bracket 801 is mounted to the top end of the cylindrical stand 105 and carries a drive motor 802 which is driven for rotation by an electric signal from a later described photoelectric sensor 804. A roller 803 is fixed to the output shaft of the drive motor 802 in pressure contact with the outer wall 205a of the bottom flange 205 on the suction assembly 201 located at the second station II. As the roller 803 rotates in the direction of an arrow "c", the flange 205 rotates in the direction of an opposite arrow "d" in Fig. 10 due to the above-described pressure contact.
The photoelectric sensor 804 is arranged at a proper position on a straight horizontal line passing through the center axis of the suction assembly 201 located in the second station II. The sensor 804 detects presence of the cut edge 5 and the seam lines 3a and 4a on the incomplete panty-hose 7a held on the suction assembly 201 in the second station II.
As the sensor 804 detects presence of the cut edge 5, its electric detection signal drives the motor 802 for rotation. The motor 802 ceases its rotation, however, as the sensor 804 detects presence of the seam lines 3a and 4a. In other words, the sensor 804 detects presence of the cut edge 5 when the seam lines 3a and 4a are off the straight line X and the motor 802 is driven for rotation. As a consequence, the roller 803 rotates in the direction "c" and the flange 205 in the direction "d". As the seam lines 3a and 4a meet the straight line X, the sensor 804 detects this and the motor 802 ceases its rotation. When the seam lines 3a and 4a are on the straight line X from the beginning, the motor 802 does not rotate at all. In either case, the seam lines 3a and 4a are registered at the straight line X by the sensor 804 before the cut edge 5 and the marginal edge of the gore piece 10 are superimposed.

(7) The sewing machine 601

The sewing machine 601 is arranged in the third station III in order to seam the cut edge 5 of the incomplete panty-hose 7a held by the suction assembly 201 with the marginal edge of the gore piece 10. The construction is shown in Fig. 8.
At the moment the suction assembly 201 with the incomplete panty-hose 7a and the gore piece 10 arrives at the third station III after its travel along the guide plate 423, the gore piece 10 is in the flat state but the marginal portion of the cut edge 5 is folded over the suction tube bottom flange 205. Prior to starting of the seaming operation, the marginal portion of the cut edge 5 needs to be returned to the flat state for snug superimposition with the marginal edge of the gore piece 10. This flattening is carried out on the sewing table 603.
One example of such flattening is carried out by an air ejection nozzle 604 arranged near the sewing machine 601 with its ejection mouth closely facing the outer wall of the suction tube bottom flange 205. Air blow by the nozzle 604 flattens the marginal portion of the cut edge 5 on the gore piece 10.
Another example of such flattening is carried out by an air suction nozzle 605 located at an upstream position of a sewing needle 601 a on the sewing machine 601. Air suction by the nozzle 605 flattens the marginal portion of the cut edge 5 on the gore piece 10.
These are nozzles 604 and 605 may be used in combination.
It is also feasible to arrange these air nozzles 604 and 605 at the second station II in order to practice the flattening of the marginal portion just after transfer of the gore piece 10 to the suction assembly 201. In this case, however, there is a likelihood that the once flattened marginal portion of the cut edge 5 may loose its correctly superimposed state due to any unexpected shock to be caused during its travel to the third station III with the suction assembly 201. In order to avoid such a trouble, it is rather advantageous to carry out the flattening of the marginal portion of the cut edge 5 at the third station III.

(8) The removing assembly 701

The complete panty-hose 7 formed at the third station III is removed off the suction assembly 201 at the fourth station IV in order to be discharged from the apparatus.
The removing assembly 701 is shown in detail in Fig. 3.
One end of a delivery pipe 703 is coupled to the circular hole 123 (see Fig. 6) in the cover disc 120.
The other end of the delivery pipe 703 is provided with a delivery mouth 704. A pair of vertically spaced brackets 705 are disposed on the cover disc 120 and the operation table 102 in axial alignment, respectively, in order to hold a suction pipe 706 vertically. This connection holds the cover disc 120 inmovable with respect to the main shaft 103 which rotates intermittently. The upstream end of this suction pipe 706 is coupled to the suction tube 108 with the downstream end to the delivery mouth 704.
Thus, pneumatic suction acts on the complete panty-hose 7 within the suction tube 201 via the suction pipes 108 and 706, the delivery mouth 704, the delivery pipe 703 and the circular hole 123. As a consequence the complete panty-hose 7 is discharged from the apparatus via the circular hole 123, the delivery pipe 703 and the delivery mouth 704.
Operation of the automatic seaming apparatus in accordance with the present invention is hereinafter described with reference to Figs. 9A to 9E.
In the first station I, pneumatic suction acts on a suction assembly 201 by switching it on so that, as shown in Fig. 9A, the leg sections of an incomplete panty-hose 7a are sucked into the suction tube 203 and the marginal portion of the cut edge 5 is manually folded over the bottom flange 205. Even after the pneumatic suction is terminated, the incomplete panty-hose 7a is held on the suction assembly 201 by the hooks 206 (see Fig. 2). The suction assembly 201 then travels towards the second station II whilst carrying the incomplete panty-hose 7a as shown in Fig. 9B.
In the second station II, the feeder assembly 301 passes a gore piece 10 cut into a predetermined shape to one double drum 410 of the transfer assembly 401. Thereafter, the valve 426 is rendered open in order to suck the gore piece to the top face of the associated semi-circular plate 408. In synchronism with the travel of the suction assembly 201 to the second station II, the double drum 410 revolves about the axis of the support shaft 405 over 180 degrees and is registered at a position below and in axial alignment with the suction assembly 201 arrived at the second station II.
Further, by operation of the direction adjuster assembly 800, the angular position of the marginal portion of the cut edge 5 is carried by the flange 205 of the suction tube 203 is adjusted relative to the gore piece 10.
At this moment, the valve 426 is closed in order to cancel the pneumatic suction working on the gore piece 10 on the semi-circular plate 408 and the pneumatic cylinder 415 starts to lift the double drum 410, thereby placing the gore piece 10 on the semi-circular plate 408 into pressure contact with the marginal portion of the cut edge 5 on the flange 205 as shown in Fig. 9C.
Concurrently with this procedure, the heat cutting assembly 501 forms cuts in the marginal portion of the cut edge 5.
As these operations are complete, the suction assembly 201 with the incomplete panty-hose 7a travels towards the third station III. The gore piece 10 on the semi-circular plate 408 in the lifted position slides towards the sewing table 603 along the guide plate 423 due to the above-described pressure contact.
In the thrid station III, the marginal portion of the cut edge 5 is turned back to the horizontal state by operation of the air ejection nozzle 604 and/or the air suction nozzle 605 in order to be superimposed on the marginal edge of the gore piece 10. At this moment, the suction tube driver assembly 50 operates to rotate the suction tube 203 with the incomplete panty-hose 7a and the gore piece 10 over 360 degrees so that the sewing machine 601 seams the marginal portion of the cut edge 5 together with the marginal edge of the gore piece 10. This procedure is shown in Fig. 9D. Concurrently with this seaming, the surplus sections of the marginal portion and the marginal edge are cut off and a complete panty-hose 7 such as shown in Fig. 9E is obtained which includes an almost round gore 10a seamed to the opening 5a along the seam line 8.
As the seaming is complete, the suction assembly 201 travels towards the fourth station IV whilst carrying the complete panty-hose 7 inside. The removing assembly 701 thereupon operates to remove the panty-hose 7 off the suction assembly 201 and discharge from the apparatus.
In accordance with the present invention all operations are carried out automatically except for the initial manual attachment of the incomplete panty-hose to the suction assembly in the first station. This naturally results in remarkable saving in labour, high production efficiency and low production cost.
Operations done by the automatic assemblies assure production of panty-hoses of uniform quality and shape.
The temporary application of pneumatic suction only in the first station for holding of the incomplete panty-hose results in reduced power consumption and simple piping for the pneumatic system.
As the suction assemblies travel along a circular endless path, the apparatus is very compact in construction and less space is necessary for its installation.

Claims

1. Automatic seaming method for gored panty-hoses (7), comprising the steps of holding an incomplete panty-hose (7a) having an unseamed opening (5a) defined by a cut edge (5), on a pneumatic suction assembly (201) by application of pneumatic suction with a marginal portion of the cut edge exposed outside one end of the suction assembly, superposing a flat gore piece (10) with its marginal edge aligned with the marginal portion of the cut edge, seaming together the marginal edge with the marginal portion to form a complete panty-hose while rotating the marginal edge and the marginal portion through an angle of 360° about the axis of the suction assembly, pneumatically removing the complete panty-hose from the suction assembly, characterized in that the application of pneumatic suction is temporary and that further holding of the incomplete panty hose is effected by hooks arranged within the suction assembly, that the marginal portion of the cut edge is folded over the end of the suction assembly, and at least one cut is formed therein to extend from the cut edge inwardly of the marginal portion prior to the superimposition which is carried out by unfolding the marginal portion of the cut edge over the marginal edge of the gore piece.

2. Automatic seaming method as claimed in claim 1 in which said at least one cut is formed by means of heat cutting.

3. Automatic seaming method as claimed in claim 1 or 2 in which the steps of holding the incomplete panty-hose, superposing the gore piece, forming the cut, unfolding the marginal portion seaming, and removing of the completed panty-hose, are completed as said suction assembly moves along an endless path.

4. Automatic seaming method as claimed in any one of claims 1 to 3 in which said unfolding of said marginal portion is carried out by means of pneumatic blow.

5. Automatic seaming method as claimed in any one of claims 1 to 4 in which said unfolding of said marginal portion is carried out or assisted by means of pneumatic suction.

6. Automatic seaming method as claimed in any one of claims 1 to 5 further comprising detecting, in advance of said seaming, by photoelectric means (804) whether or not seam lines (3a, 4a) and the cut edge (5) of said incomplete panty-hose are in correct positions, and registering said seam lines (3a, 4a) at said correct positions when they are off said correct positions.

7. Automatic seaming method as claimed in any one of claims 3 to 6 in which the steps are carried out at four different stations arranged equidistantly along said endless path, and said suction assembly travels with said incomplete panty-hose from the first to third station and with said complete panty-hose from the third to fourth station, intermittently with a dwell at each station.

8. Automatic seaming method as claimed in claim 7 in which said holding of said incomplete panty-hose is performed at said first station, said superposing of said gore piece is performed at said second station, said seaming is performed at said third station, and said removing is performed at said fourth station.

9. Automatic seaming method as claimed in claim 8 in which concurrently during the operations on one panty-hose being performed at the different stations, the operations on a plurality of other panty-hoses are being performed at the other stations within common dwells.

10. Automatic seaming apparatus for gored panty-hoses comprising suction means (201) for holding an incomplete panty-hose (7a), a sewing machine (601) for seaming together the marginal edge of a gore piece (10) with a marginal portion of a cut edge (5) of the incomplete panty-hose (7a) to form a complete panty-hose while. rotating the panty-hose together with the gore piece through an angle of 360°, and a pneumatic suction removing assembly (701) for removing the complete panty-hose from the suction means (201), characterized by support means formed by a horizontal operation table (102) having at least four separate operation stations (I, II, III, IV) arranged equidistantly along an endless path, at least four suction assemblies (201) being arranged over said operation table, each being adapted for holding an incomplete panty-hose (7a) and each including a vertical suction tube (203) provided with a bottom flange and at least one inner hook (206), means (109) for concurrently driving said four suction assemblies (201) for travel from station to station along said path in an intermittent fashion with dwells so that each said suction assembly (201) rests at any station during said dwells, a gore piece feeder assembly (301) located adjacent the second station (II) for sequentially feeding gore pieces (10) of a predetermined pattern, one at a time, in an intermittent fashion, a gore piece transfer assembly (401) interposed between said second station (II) and said feeder assembly (301) for transferring, in a flat state, each said gore piece received from said feeder assembly to a suction assembly (201) during a dwell when this suction assembly is located at the second station, a heat cutting assembly (501) arranged adjacent said second station (II) for forming at least one cut in the marginal portion of the cut edge (5) held by said suction assembly (201 means (604, 605) for unfolding said marginal portion into superimposed position with the marginal edge of said gore piece (10), a flat guide plate (423) extending between said second and a third station (I1, III), a suction tube driver assembly (50, 51, 53, 55) arranged at said third station (III) for driving said suction tube (203) of said suction assembly (201) in said third station through an angle of 360 degrees, said sewing machine (601) being arranged at said third station (III) and provided with a sewing table (603) flush with said guide plate (423) for seaming said superimposed marginal portion and marginal edge together during driving through said angle of 360 degrees in order to form a completed gored panty-hose during each said dwell, said removing assembly (701) being located at the fourth station for removing, by means of pneumatic suction, said complete gored panty-hose off said suction assembly (201) when located at said fourth station, and a pneumatic suction source (108a) being connectable to said transfer assembly (401), removing assembly (701) and the suction assemblies (201) when located at said first station (1).

11. Automatic seaming apparatus as claimed in claim 10 characterized in that said operation table (102) takes the form of a round table having said endless path extending along its periphery, said driving means includes a vertical cylindrical main shaft (103) which is intermittently rotatable about its longitudinal axis through an angle of 90 degrees, and a horizontal carrier disc (104) mounted atop said main shaft, and said four suction assemblies (201) depend from the bottom of said disc (104) at equal distances along its periphery.

12. Automatic seaming apparatus as claimed in claim 10 or 11 characterized in that the interior of each said suction assembly (201) is connected to a suction terminal (108) of said suction source via a manually shiftable valve and said main shaft (103).

13. Automatic seaming apparatus as claimed in any one of claims 10 to 12 characterized in that said gore piece feeder assembly (301) includes a feed reel (303) of a gore piece material band, means for delivering said gore piece band from said feed reel (303) intermittently in sections having a length corresponding to each said gore piece, a pair of cutters (312, 313) arranged downstream of said feed reel for delineating each delivered section of said gore piece band, and a cutter (314) arranged downstream of said pair of cutters for cutting each said delivered section into each said gore piece.

14. Automatic seaming apparatus as claimed in any one of claims 10 to 13 characterized in that said gore piece transfer assembly (401) includes a vertical, cylindrical, center support shaft (405) rotatable about its longitudinal axis in an intermitted fashion such that each rotation covers 180 degrees, a pair of double drums (410) held by said support shaft at opposite diametric positions, the interior of each said double drum being connected to a suction terminal (108) of said suction source via said support shaft, a perforated semi-circular plate (408) closing a top opening of each said double drum and having a top face flush with that of said guide plate (423), means (414) for elastically pushing said drum downwards, and means (415, 415a) for thrusting up said drum against the pressure by said elastic pushing means to an extent such that a gore piece placed on said semi-circular plate (408) is placed in pressure contact with said marginal portion of the cut edge of said incomplete panty-hose held by said suction assembly (201).

15. Automatic seaming apparatus as claimed in any one of claims 10 to 14 characterized in that said heat cut assembly (501) includes at least one heated cutter (517, 523), at least one movable arm (515, 521) holding, at its free end, said heated cutter, and means for driving said arm for movement between operative and inoperative positions so that said heated cutter contacts, in said operative position, said marginal portion of the cut edge of said incomplete panty-hose held by said suction assembly (201).

16. Automatic seaming apparatus as claimed in any one of claims 10 to 15 characterized in that said unfolding means (604, 605) includes at least one of an air ejection nozzle (604) and an air suction nozzle (605) located closely adjacent said marginal portion of said cut edge (5) located at said third section (III).

17. Automatic seaming apparatus as claimed in any one of claims 10 to 16 characterized in that said suction tube driver assembly includes a gear (204) attached to said suction tube (203) of each said suction assembly (201) and a drive motor (53) arranged at said third station (III) and provided, on its output shaft, with a gear (55) for engagement with said gear on said suction tube.

18. Automatic seaming apparatus as claimed in any one of claims 10 to 17 characterized by means (800) arranged at said second station and for detecting, in photoelectric manner, whether or not seam lines (3a, 4a) and the marginal portion of the cut edge (5) held by said suction assembly (201) are in correct positions, said suction tube (203) of said suction assembly (201) being rotated by said detecting means (800) until said seam lines are registered at said correct positions.

19. Automatic seaming apparatus as claimed in any one of claims 10 to 18 characterized in that said removing assembly (701) includes a delivery pipe (703) connectable at its one end to a top opening of each said suction assembly (201) then located at said fourth section, a delivery mouth (704) coupled to the other end of said delivery pipe, and a suction pipe coupled at its one end to said delivery mouth (704) and at its other end to a suction terminal (108) of said suction source.