US 3711866 A
The invention relates to a method of producing panty hose in which in a first step two hip length stockings are knitted for each panty hose, which are then drawn over shaped forms as usually used for boarding or plasticizing stockings, after the plasticizing and dyeing operation while the stockings are still on the shaped forms, being arranged side-by-side upright or in a horizontal position those portions of the stockings providing the hip portions of the finished panty hose are drawn together and sewed together in such a manner, that first and second portions of a seam are produced the first one lying on the front side and the second one lying on the rear side of the finished panty hose; therefore the pitting between said seam portions can be cut through, preferably while the stockings are still arranged on said shaped forms.
Description (OCR text may contain errors)
[ 1 Jan. 23, 1973 METHOD AND APPARATUS FOR PRODUCING PANTY HOSE Fritz Vorberg, Winkl, Germany  Inventor: Bischofswiesen-  Assignee: Globotex AG, Zug, Switzerland  Filed: Feb. 10, 1969 ("211 Appl. No.1 797,345
 U.S.Cl ..2/224R,l12/121.14
Primary Examinerl-l. Hampton Hunter Att0rney-Mason, Kolehmainen, Rathburn & Wyss  ABSTRACT The invention relates toa method of producing panty hose in which in a first step two hip length stockings are knitted for each panty hose, which are then drawn over shaped forms as usually used for boarding or plasticizing stockings, after the plasticizing and dyeing operation while the stockings are still on the shaped forms, being arranged side-by-sidc upright or in a horizontal position those portions of the stockings providing the hip portions of the finished panty hose are drawn together and sewed together in such a manner, that first and second portions of a seam are produced the first one lying on the front side and the second one lying on the rear side of the finished panty hose; therefore the pitting between said seam portions can be cut through, preferably while the stockings are still arranged on said shaped forms.
6 Claims, 9 Drawing Figures PATENTED 97 3. 71 1. 866
sum 1 0F 8 A TTOR/VAFY PATENTEDmza 191s 3.711.866
sum 2 OF 8 Fig. 3
PATENTEU JAN 2 3 I973 SHEET UF 8 PATENTEDJAN 23 Ian SHEET 5 OF 8 PATENTED JAR 23 I975 SHEET 7 OF 8 PATENIEDJMI 23 I915 SHEET 8 BF 8 METHOD AND APPARATUS FOR PRODUCING PANTY HOSE BACKGROUND OF THE INVENTION This invention relates to panty hose consisting of two approximately hip length stockings which, from the top welt or waistline to approximately the region of the crotch, are provided with an incision and in which the edges of said incisions are joined together by a seam. The invention relates, furthermore, to a method of producing panty hose in which two hip length knitted stockings are drawn over or mounted upon flat template-like shaped forms such as are applied for forming,
' boarding and plasticizing stockings and in which, in a subsequent processing step, the two stockings are joined together by seams along two incisions running from the top welt of waistline to approximately in the region of the crotch. Finally, the invention relates to an apparatus by which this method can be carried out.
Heretofore panty hose were made in such a manner in that two waist or hip long individual stockings, after having been dyed, boarded and plasticized were each provided with an incision by hand, running from the top welt to the region of the crotch, whereupon the edges of the incisions of both stockings were likewise manually joined together, with the aid of a sewing machine, by means of a continuous seam. Said continuous seam consequently had the shape of a U. As is known, the dyeing and plasticizing or boarding of the stockings is performed on flat, template like forms, having the shape of a leg, which, in the following, are referred to as shaped forms. In conventional production, the individual stockings are drawn off these forms prior to incising and seaming. The known method has the substantial disadvantage that as a result of the many manual steps involved in the production, such production of panty hose is relatively high in labor consumption and therefore expensive.
One object of the invention is to make the production of panty hose more economical than up to now. A further object of the invention is the design of panty hose which is especially suited for automatic production as far as possible.
SUMMARY OF THE INVENTION According to the invention two hip-length stockings are drawn over template-like shaped forms, which are to be arranged side-by-side in a congruent position, whereupon the zones of both stockings facing each other that are to be joined together are moved towards each other and brought into contact at least approximately and finally sewed together, while said stockings are still on the shaped forms.
In this manner the stockings need no longer be adjusted for sewing together, as was formerly the case when sewing the stockings together on a conventional sewing machine, as they already are in a predetermined position on the shaped forms. Consequently the seams can readily be made automatically and always in the same place which is a fundamental prerequisite for an automation of the sewing process, this having formerly been the step that required the most manual labor in panty hose production.
A panty hose especially suited for automatic sewing was designed according to the invention with two approximately hip-length stockings, each provided with an incision extending from the top edge to approximately the zone of the crotch, and in which the two incision edges of both stockings located on the front of the panty hose are joined by a first seam and the two incision edges on the rear are joined together by a second seam, said seams are arranged approximately in parallel to each other.
Two such parallel seams can readily be produced by a conventional sewing machine by moving the latter along a straight feed line. The resulting opening in the zone of the crotch, which is a result of the fact that the two seams do not overlap, can be kept down to a very small size, so that it practically does not disturb and is not noticed at all during wear. But the sewing machine could also be designed that the two seams converge and overlap, so that in the zone of the crotch a completely closed panty hose is formed.
A further step toward complete automation can easily be made to follow. According to the invention, it is advisable to cut through the knitting of the stockings after sewing between the two seams, while the stockings are still on the shaped forms. Namely, as long as the stockings are still on the shaped forms it is not only a very easy matter to make the seams at a predetermined place, but the cutting of the knitting can then reliably be done always at the same predetermined position, without having to bring} the stockings or the panty hose once more into alignnient. A very plain apparatus for effecting the method "according to this invention has at least four straddling or expanding means, arranged in pairs, that move towards each other and press together the zones of the two stockings that are to be sewed together, two such straddling or expanding means being disposed for each single stocking and arranged spaced apart from each other and, in each case, between the respective shaped form and the stocking. Such straddling bars can readily be inserted between stocking and shaped form, so that the zones of both stockings that are to be sewed together are reliably brought into contact with each other. If the zones of two hip length stockings facing each other are drawn together, that is, the prospective hip portions of a panty hose, then a conventional sewing machine, for example, of the type feed-off-the arm machine can be applied. Thus, in a favorable embodiment of the apparatus according to this invention, sewing is done by a sewing machine having two arms that can be introduced between the shaped forms and the stockings in order to sew together stockings that have been drawn together. If appropriately constructed, such a sewing machine can produce, in one operating cycle, the two parallel seams, between which the knitting can then be slitted or melted through. Melting through ought to be preferred because technically it calls for the least expensive arrangement, namely, a heated filament or wire, or similar means.
The incision in the individual stocking could, as such, also be made before sewing the stockings together, as has been customary in the method of panty hose production heretofore in practice; it is, however, recommendable, to sew first and then to cut, because means for securing the edges of the incisions until the sewing step is completed can then be eliminated. According to a further feature of this invention, the sewing and cutting can be done in one operation, thus making the production method especially time saving and economical. To this end the apparatus according to this invention is provided with a cutting means for slitting the knitting of the stockings between the two seams which, in its simplest embodiment, comprises an electrically heated wire or filament, movable in the lengthwise direction of the shaped forms and, for reasons of expediency, disposed on the sewing machine in such a manner that it lies behind the sewing means, as seen in feed direction of same. In this manner the seams are made first and shortly behind the point at which the seam has just been made the heated filament cuts the knitting of the stockings between the two seams.
Further details and features of the invention will be seen in the attached drawings and the following specification that serve to explain the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an embodiment of a panty hose according to this invention, in the form it assumes during wear;
FIG. 2 is a side view of said panty hose laid together in the form in which it is usually delivered;
FIG. 3 is a section of an apparatus for the continuous production of stockings, shown in perspective view;
FIG. 4 is a perspective view of a section of the apparatus shown in FIG. 3, together with a sewing station for sewing together two hip length separate stockings to form one panty hose, whereby a sewing machine and four expander bars to being into contact the zones of two stockings that are to be sewed together are shown in idle position;
FIG. 5 represents FIG. 4 with the expander bars in elevated position;
FIG. 6 corresponds to FIG. 5 but with the expander bars brought together;
FIG. 7 a representation corresponding to FIG. 6 in which the sewing machine is in its upper endmost position;
FIG. 8 a section according to the line 8--8 in FIG. 7;
FIG. 9 a section of a cross sectional view, corresponding to the line 9-9 in FIG. 8, showing the position of the sewing machine in which the cutting of the knitting between the parallel seams is just commencing.
DESCRIPTION OF THE PREFERRED EMBODIMENTS The panty hose shown in FIG. I has been produced of two separately manufactured hip-length stockings 10 that are joined together along two seams l2, 14. These seams extend from the upper rim of the panty hose to crotch 16. Within the region of the crotch each stocking has a reinforced and ladderproof strip 18 that separates the leg portions 20 of the stockings from the hip portions 22. For reasons of expediency the hip portions are also made ofladderproof knitting, as known in the art under the designation of micro-mesh and pinpoint. Likewise for reasons of expediency there are elastic threads knitted into the upper hip portions, so that an elastic double welt 24 can be formed.
As is clearly recognizable in FIG. 2, the seams l2 and 14 terminate at or in the strip 18, whereas the knitting between the two seams is advantageously cut open or burnt away somewhat above the lower end of the seams; there is thus created in each of the two stockings 10 the incisions 26, the edges of which are joined together by the seams 12 and 14, so that the panty hose properly results from said operations.
The section of an apparatus illustrated in FIG. 3 for the continuous production of panty hose shows a chain conveyor 30 that is drawn forward on a bed, not shown here, e.g., according to FIG. 3 to the right side. Chain 30 is composed of multiple flat rods 32 connected pairwise by joint bolts 34. To the flat rods 32 there are welded jib arms 36 to which the shaped forms 38 are secured, which may also be done by welding. Said shaped forms are known in the art because they are applied for plasticizing and boarding normal or hip-length stockings as used in the manufacture of panty hose. Said shaped forms are flat, leg-shaped metal templates which may, e.g., be of aluminum. According to the present invention, however, straddling brackets 40 are secured to these conventional shaped forms in such a manner that two straddling brackets are secured to each of the shaped forms on the sides of said shaped forms that face each other. It is expedient to likewise weld said straddling brackets to the shaped forms and they are given rigidity by the crosspieces 42 and 44. In place of these straddling brackets it would also be possible to provide two parallel grooves running from bottom in upward direction and spaced apart on the two sides of shaped forms that face each other, in order to insert, from the bottom to the top, between stocking and shaped form, the expander bars that will be explained below. Said expander bars would merely have to be dimensioned so that they could be shoved into the grooves.
In the upper half of FIG. 4 there is shown a section of the conveyor chain 30 with only two shaped forms 38, the upper parts of which have been broken away. In like manner the same FIGURE also does not show the bed on which conveyor chain 30 runs. Directly under the shaped forms there is shown the sewing station according to this invention which, in its entirety bears the reference numeral 50. It comprises a sewing machine, bearing as a whole the reference number 52, supported by a lifting cylinder 54, and four expander bars 56 arranged pairwise which are mounted on a common guide bar 58, that will be described below, for transverse movement and that can be lifted by two lifting cylinders 60. It is pointed out that the lifting cylinder 54 and 60 may be either of the pneumatic or hydraulic type.
In detail, according to FIG. 4, the sewing machine 52 has a left arm 62 in which the needles 64 and, in a predetermined distance above same, an electrically heated wire 66 are installed. According to FIG. 4, a right arm 68 of sewing machine 52 accommodates the other components of said machine such as the feed mechanism. An electric driving motor 71 is directly flanged to the sewing machine and is supplied with current by lead 73.
A detailed description of the sewing machine can be dispensed with as a person skilled in the art readily knows which types of sewing machines can be applied in the realization of this invention. For practical reasons the embodiment shown here is a two-needle, four-thread, feed off-the-arm double chain stitch sewing machine, as e.g., sold by the Union Special Machine Co., Chicago, U.S.A. An especially suitable machine, e.g., is the type 35700 made by Union Special, that is capable of producing two seams of the type 401 that run parallel to each other. It goes without saying, that it is naturally possible for a person skilled in the art to also apply other machines and to modify same in regard to seam length and type of scam as well as in regard to the mounting of the drive and to provide the electric heated wire or other cutting means separated from the actual sewing machine. The conditions to be laid down for the sewing machine are solely that the two arms must not be so thick that they no longer could be inserted between the stocking and the shaped form and that the machine is capable of producing seams of the required length and properly spaced in regard to each other, furthermore, that said seams warrant an adequate strength and elasticity of the panty hose within the zones adjoining said seams.
FIG. 4 shows further details of the sewing station according to this invention: two expander bars each are attached to each base plate 70 that is transversely slidable on guide bar 58. On each base plate, opposite the expander bars, the piston rod 72 of an expander bar actuating cylinder assembly 74 engages each base plate, said cylinder again being either a pneumatic or a hydraulic cylinder, secured to the guide bar by a mounting bracket 76. Said cylinder, like the cylinders 54 and 60, also has pressure tubes 78 for the inflow and outflow of pressure fluid and whereas the cylinders 54 and 60 may be single-acting cylinders, as they are only required to lift the sewing station, for said station can be automatically lowered by gravity,the expander bar actuating cylinders 74 must be double-acting cylinders that not only lead the expander bars towards each other, but also return them again to the positions shown in FIG. 4 and 5.
It also deserves mention that the expander bars 56 are bevelled at the top, so that they can still also easily be introduced between the stocking and the shaped form in cases where no expanding brackets 40 are secured to the shaped form.
For dyeing and plasticizing or boarding the greige stockings coming from the circular knitting machine are drawn over the shaped form. In FIG. 8 two stockings are represented and referenced by 80. Already in drawing the stockings over the shaped forms, but at least always for two stockings that belong together, care must be taken that the top welts, which later form the elastic double welt 24 of the panty hose, are extended to the same level, for example, to the level of the crosspieces 44. After the stockings have travelled the path of the chain conveyor 30 and have been dyed, plasticized and dried before reaching sewing station 50, they are conveyed in the steps of the conveyor chain 30 advance to sewing station 50 which is initially in the position shown in FIG. 4.
Then the expander lifting cylinders 60 advance upwards, whose piston rods 61 are secured to the guide bar 58. The expanders now assume the position shown in FIG. 5 in which they are already stationed between the shaped forms 38 and the stockings 80 on the shaped forms that have been drawn over the straddling brackets 40. On an embodiment with grooves in the shaped forms the expander bars 56 will have to be of somewhat flatter form in order that they will be able to move faultlessly along the grooves between stocking and shaped form, so that straddling brackets 40 can be dispensed with.
In the next step the two expander pairs are moved towards each other by means of expander bar actuating cylinders 74, so that the expander bars assume the positions shown in FIG. 6. In this position they stretch the stockings still more so that the zones of the stockings that are to be sewed together are side by side, as shown in FIG. 8.
The next step is made clear in FIG. 7 for now the sewing machine 52 is brought into its uppermost end position by means of the sewing machine lifting cylinder 54, whereupon the driving motor and with this the sewing machine are put into operation. It now begins at or in the strips 18 to form the two seams 12 and 14, as shown in FIG. 9, whereby simultaneously piston rod 55 that supports the sewing machine in sewing machine lifting cylinder is evenly lowered, which is effected by gravity and the control of the discharge of the pressure fluid filling said cylinder. After the seams l2 and 14 have been formed for a short distance the heating current for the electrically heated wire 66 is switched on so that the knitting of the stockings between the two seams is cut through as if by a welding torch, giving rise to incisions 26 in the two stockings 80, as also shown in FIG. 9. The heated wire 66 must naturally project so far that it contacts the knitting of both stockings (see FIG. 8).
The sewing machine is then lowered to such an extent that its arms 62, 68 are retracted from the stockings and the electrically heated wire separates the knitting down to the elastic double welt 24, thus forming the finished panty hose. After lowering the sewing machine 52, the expanders 56 are again retracted by means of the actuating cylinders 74 and then brought into their starting position illustrated in FIG. 4. The finished panty hose can now be removed from the two shaped forms 38 whereupon the chain conveyor advances another step, so that two new not yet sewed together stockings 10 or 80 come to stand over the sewing station 50.
It goes without saying that the sewing machine 52 and the cutting device 66 could also be constructed in such a manner that the sewing machine sews while being raised and the cutting device cuts open the knitting either during raising or lowering. It would then merely be necessary to apply a feed-on-the-arm sewing machine. Such machines are also on the market, e.g., obtainable from Union Special Machine Co. In addition it would be possible to apply a mechanical cutting device in place of the electrically heated wire and, finally, an electrically heated wire or a mechanical cutting device can be applied to cut off the threads of the sewing machine after finishing the seams 12 and 14.
In conclusion, it might also be recommendable to provide clamping elements on the shaped forms to prevent lifting up the stockings when raising the expanders and introducing the latter between shaped form and stocking, so that the upper welts are no longer on the same level. To this end hydraulically or pneumatically actuated pressing clamps for the broad sides or edges of the shaped forms 38 could be recommended once the stockings are drawn over the shaped forms.
While the preferred embodiments of the present invention have been illustrated and described in detail, various additions, substitutions, modifications and omissions may be made thereto without departing from the spirit of the invention as defined by the appended claims.
1. A method of producing panty hose comprising the steps of: drawing two hip-length knitted stockings over template-like shaped forms, arranged side-by-side in a congruent position, moving the zones of both stockings facing each other that are to be joined together towards each other, bringing said zones closely together, sewing said stockings together while said stockings are held on the shaped forms by running two seams generally parallel to each other from the zone of the crotch to the top edge of the stockings, and cutting the knitting of the stockings through between both seams while the stockings are on the shaped forms.
2. Apparatus for sewing panty hose, said apparatus comprising sewing means, at least two template-like shaped forms for supporting hip-length stockings to be drawn thereover, at least four straddling elements arranged pairwise, means for moving said pairs of straddling elements towards each other for pressing together the stockings on said shaped forms within the zones facing each other in which said stockings are to be sewed together, at least two of said straddling elements being provided for each stocking and spaced apart from each other, means for positioning said straddling elements for each stocking between each shaped form and its stocking, said sewing means including arm means means for introducing said arm means between the shaped forms and the stockings for sewing together the expanded stockings, and cutting means for slitting the knitting of the stockings between the two scams.
3. Apparatus as set forth in the claim 2 wherein the sewing means and straddling elements are longitu dinally movable in relation to the shaped forms.
4. Apparatus as set forth in claim 2, wherein the cutting means has an electrically heated member longitudinally shiftable along the shaped forms.
5. Apparatus as set forth in the claim 2 wherein the cutting means is disposed on the sewing machine.
6. Apparatus as set forth in claim 5 wherein the cutting means is disposed behind the sewing means of said sewing machine.