Patent Abstract:
The invention concerns a knitting machine comprising two needle beds for guiding knitting needles, means for selecting said knitting needles, carriages for moving the selected knitting needles and members guiding the knitting thread. The method consists in arranging the needle beds so that the needles of a needle bed in their normal knitting travel do not cross the needles of the other needle bed, in moving the carriage in one direction along each needle bed, the displacement directions of said carriages along their respective needle beds being opposite relative to each other and in transferring the thread from the needles of one needle bed to those of the other needle beds, each time said thread reaches the end of the selected needles.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation application of PCT/IB01/00232 filed Feb. 21, 2001, which claimed priority of European Patent Application No. 00810150.3 filed Feb. 23, 2000, entitled “Method and Knitting Machine for Rectilinear Knitting to Form a Tubular Seamless Knitted Material” which are included in their entirety by reference made hereto. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a method for forming a seamless tubular knit on a rectilinear knitting machine comprising two sections for guiding the knitting needles, means of selecting these knitting needles, carriages for displacing the selected knitting needles and members for guiding the knitting yarn, and to a rectilinear knitting machine for implementing this method. 
     2. Description of the Related Art 
     Conventional rectilinear knitting machines could possibly knit seamless tubular articles, with a few modifications, especially articles formed from two tubular elements joined into a single tubular element, such as a pair of pants. However, they are not able to produce such articles with a sufficiently dense knit to make trouser fabric. Nor do they allow production under economically viable conditions, since the production rate would be so much smaller. Circular machines do not allow either the production of tubular elements side by side, or the production of tubular elements of variable diameters, or else elements which depend on the uniformity of the knit, by varying, for example, the tension of the yarn, the density of the stitches, etc. 
     The aim of the present invention consists in producing a seamless tubular knit on a rectilinear knitting machine, capable of overcoming, at least in part, the aforementioned drawbacks. 
     BRIEF SUMMARY OF THE INVENTION 
     To this end, the object of the present invention is first of all a method of forming a seamless tubular knit on a rectilinear knitting machine of the aforementioned type, as defined by claim  1 . 
     Preferably, this method relates to the formation of two tubular bodies then joined into a single tubular body, making it possible to produce a seamless pair of pants. 
     The subject of this invention is also a knitting machine for implementing the knitting method, as defined in claim  3 , and a pair of pants, boxer shorts or tights obtained by implementing this method. 
     This invention has the advantage of allowing the manufacture of a novel product under favorable economic conditions. A seamless pair of pants or boxer shorts, whatever the size, is in fact an unknown article, given that it is not yet known how to produce it. 
     It should be noted that one of the advantages of the method which is the subject of the invention resides in the fact that the diameter of the tubular part or parts of this article may vary so as to give the latter the desired shape. 
     In fact, as will be realized during the following description, the knitting method according to the invention cannot be implemented on a conventional rectilinear knitting machine, but requires a novel rectilinear machine concept, thus explaining that it is only by imagining a novel knitting concept, radically different from that usually implemented in rectilinear knitting machines, that the invention has been able to see the light of day. Indeed, it was necessary to create a concept making it possible to knit two different knitted webs, one on each section, while continually joining them by a transfer of the knitting yarn from one section to the other, thus allowing the formation of a seamless tubular element. Starting from this principle, it becomes possible to imagine the simultaneous production of two tubular elements side by side, which can then be joined into a single tubular element by selecting the needles separating the two tubular elements. 
     The invention will be better understood on referring to the following description and to the appended drawings which illustrate, schematically and by way of example, two implementational modes of the method which is the subject of the present invention, relating to two embodiments of the machine which is also subject of this invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a knitting machine according to the first embodiment; 
     FIG. 2 is a view in transverse section along the line II—II of FIG. 1; 
     FIG. 3 is a view in side elevation of FIG. 1; 
     FIG. 4 is a partial view on a larger scale of a detail of FIG. 1; 
     FIG. 5 is a top view of FIG. 1, illustrating only the system for transferring the yarn guides; 
     FIG. 5 a  is an enlarged view of a detail of FIG. 5; 
     FIG. 5 b  is a perspective view of FIG. 5 a;    
     FIG. 6 is an elevated view of FIG. 5; 
     FIG. 6 a  is a view of a detail of FIG. 6; 
     FIG. 6 b  is a top view of the detail of FIG. 6 a;    
     FIG. 6 c  is an enlarged view of a detail of FIG. 6; 
     FIG. 7 is a partial top view of FIG. 1 showing only the members relating to adjusting the width of the tubular knit; 
     FIG. 7 a  is an enlarged view of a detail of FIG. 7; 
     FIG. 8 is a partial top view of a detail of a carriage for controlling the knitting needles, showing a device for displacing this carriage with respect to its drive mechanism; 
     FIG. 9 is a view in side elevation of the knitting machine according to the second embodiment; 
     FIG. 10 is a view along X—X of FIG. 9; 
     FIG. 11 is a top view of FIG. 9; 
     FIG. 12 is a view along XII—XII of FIG. 9; 
     FIG. 13 is a view along XIII—XIII of FIG. 12; 
     FIG. 13 a  is a top view of the enlarged portion of FIG. 13; 
     FIG. 14 is a top view of FIG. 13; 
     FIG. 15 is a view similar to FIG. 14 of a second yarn transfer station; 
     FIG. 16 is an enlarged view of a yarn guide; 
     FIG. 17 is a view of a variant of the yarn guide illustrated in FIG.  16 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The knitting machine illustrated in FIG. 1 is a rectilinear machine comprising two sections  1 ,  2 , which form either two parallel planes or, as illustrated in this FIG. 1, the planes of these sections form an acute angle with each other such that the knitting needles  3 , in their normal knitting travel, do not cross, as illustrated in FIG.  2 . 
     It is stated that only the parts of the machine needed for understanding the invention have been shown. The usual parts of this type of machine, well known to a person skilled in the art and which are not part of the present invention have therefore not been shown. This is especially the case for the knitting needle  3  selection mechanism, and the cam mechanisms for controlling the needles secured to the carriages. 
     A plurality of carriages  4  are placed along the sections  1 ,  2 . These carriages  4  are secured to a drive chain or belt  5 . This drive chain  5  forms a closed loop which rotates around two drive disks  6 , mounted so that they can rotate about two respective vertical shafts, one  7  of which is visible in FIG.  1 . The carriages, secured to this drive chain  5 , therefore always advance in the same direction. In the example described, this direction is that of the arrow F, such that these carriages  4  pass successively from one section  1  to the other section  2  and conversely. 
     A guide rail  8  forms a closed loop whose plane is parallel and located above the closed loop, formed by the drive chain  5 . Sliding supports  9 , illustrated in more detail in FIGS. 6 a ,  6   b , are engaged with the guide rail  8  and are capable of sliding freely along this rail. A yarn guide  10  is suspended on each sliding support  9 . To this end, the upper end of the yarn guide  10  is terminated by a semicircular catching element  10   c , while the sliding support  9  comprises a longitudinal catching groove  9   a  open at its two ends, in order to allow the catching element  10   c  to exit via the rear of this longitudinal groove  9   a  and to re-enter via the front, with respect to the displacement direction of the sliding support  9 . 
     Each carriage  4  bears a bracket  11 , the horizontal arm  11   a  of which extends just under the guide rail  8 . This horizontal arm  11   a  forms a slide in which two pushers, an upper pusher  12  and a lower pusher  13 , are mounted so that they can slide, each of these pushers being secured by a peg  12   a ,  13   a , respectively. The role of these pushers  12 ,  13  is to push the sliding supports  9  and the yarn guides  10  along the guide rail  8 . The upper pusher  12  is terminated by an oblique part  12   b  intended to push the yarn guides during the operation of transferring the yarn guides, as will be seen below. 
     The knitting machine further comprises members  14  for transferring the yarn guides  10  from a knitting needle  3  bed associated with one of the sections  1 ,  2  to the knitting needle  3  bed associated with the other of these sections  1 ,  2 . Each of the transfer members  14  comprises two parts  14   a ,  14   b  (FIG. 5 a ), together forming a guide groove  16 , each of the two parts being secured to an arm  15   a ,  15   b  of a suspension member  15  (FIG.  1 ). The exit end of the guide groove  16  is closed by a retractable flap  16   a , retained by a spring  16   b  and serving to retain the yarn guide  10  when it is transferred from a knitting needle  3  bed of one of the sections to the knitting needle  3  bed of the other of the sections. 
     The yarn guides  10  comprise, along their stem, a guide portion  10   a , the cross section of which is ovalized to facilitate guiding in the guide groove  16 . The top of this guide portion  10   a  comprises a projection  10   b  intended to come into contact with the upper face of the transfer member  14 , thus defining the vertical position of the yarn guide  10 . Advantageously, the upper face of the transfer member  14  is in the shape of a cam to lift the yarn guide  10  during the transfer and thus to place it out of the range of the knitting needles  3  and to bring it back to its initial level after the transfer. 
     As can be noticed in FIG. 1, four transfer members  14  are placed along the sections  1  and  2 . The two transfer members  14  placed at the two ends are oriented so that the ends of their guide grooves  16  face inward, that is to say that they face each other. The suspension members  15  of the two other transfer members  14  located between the end members are both secured to a drive member  17  intended to orient them angularly, as will be seen below. As will also be seen in FIGS. 1,  6  and  7 , each of the suspension members  15  is also connected to an adjustment nut  18   a ,  18   b ,  18   c ,  18   d  engaged with a threaded rod  19  comprising four portions  19   a ,  19   b ,  19   c ,  19   d , threaded with reverse pitches with respect to each other. One end of this threaded rod  19  is secured to an adjustment member  20 , which may advantageously be a stepper motor. The role of this adjustment member  20  is especially to adjust the distance between the transfer member  14 . 
     The adjustment nuts  18   a ,  18   d  bear an arm  77   a ,  77   d , respectively, while the adjustment nuts  18   b ,  18   c  each bear two arms  77   b ,  77   c , respectively. 
     Each arm  77   a ,  77   d  located at one of the ends of the sections  1 ,  2  bears a cam  21   a ,  21   b  (FIGS. 1 and 7) intended to engage with a peg  13   a  of the pusher  13 . 
     Each arm  77   b ,  77   c  located in the middle part of the sections  1 ,  2  is associated with two cams  21   c ,  21   f  or  21   e ,  21   d , respectively intended to engage with the same peg  13   a , for a purpose which will be explained below. 
     As shown in the enlarged view of FIG. 7 a , the cam  21   d , borne by the arm  77   c , is secured to the end of an arm  81 , hinged at the end of the arm  77   c . A transmission belt  78  connects a pulley  79 , secured to the shaft of the drive motor  17 , to a pulley  80  secured to the hinge pin of the arm  81 . Thus the cam  21   d  borne by the arm  81  can be placed in two positions, an active position illustrated in dot-dash line in FIG. 7 a  and an inactive position illustrated in solid line in this same FIG. 7 a . The other cams  21   a - 21   f  are actuated in the same way as described above for the cam  21   d.    
     Each end of the guide rail  8  is terminated by a highly enlarged part  8   a ,  8   b . At the entrance and at the exit of each of these enlarged parts, two more or less superimposed cams  22   a ,  22   b ,  22   c ,  22   d  are arranged so as to engage with the pegs  12   a ,  13   a  of the pushers  12  and  13 . The role of the cams  22   a ,  22   c  located at the entrances of the respective enlarged parts  8   a ,  8   b , is to separate the pushers  12 ,  13  in order to release the center of each of these enlarged parts  8   a ,  8   b  in order to allow the yarn guides to be supplied with yarn from two sets of four reels  23  (in this example) each one borne by a rotating creel  24  secured to a shaft  25 . 
     A bevel gear transmission connects this shaft  25  to the shaft  26  of a geared drive motor M located at each end of the machine and which, by means of two respective transmission belts  27 , also drive the shafts  7  of the disks  6  around which the drive chain  5  of the carriage  4  passes. Each of the pins  25  of the creels also bears a take-off  28  engaged with a transmission belt  29 . A transmission shaft  30  transmits the movement received by the belt  29 , using a transmission belt  31 , to a rotating yarn guide  32 . By virtue of this arrangement, the relative speeds of the creel  24  and of the rotating yarn guide  32  may be controlled so that the various yarns do not get entangled. 
     FIG. 8 again illustrates a device for the relative movement between the carriage  4  and the drive chain  5 . To this end, the carriage  4  is connected to the drive chain  5  via a slide  33  secured to the carriage  4  and a slider  34  secured to the drive chain  5 . A servomotor  35  serves to make a worm  36  turn while engaged with the slider  34  in order to displace it along the slide  33 . The servomotor is supplied by a supply rail  37  with which a contact arm  38  comes into sliding contact. 
     Given that the knitting needles  3  do not cross, it is necessary to provide members for holding the knit during knitting. Such members  39  are visible in FIG.  4 . It can be seen that they are constructed like a sort of comb allowing the knitting needles  3  and the knitting yarns to pass. Each of these holding members  39  rests on a support bar  39   b . As can be seen in FIG. 4, the parts  39   a  of the holding members which extend above the respective upper edges of the sections  1 ,  2  are thinned, thus leaving space for the formation of stitches of the knit when the knitting needles  3  descend into the guide grooves of the respective sections  1 ,  2 . 
     It is by virtue of these holding members  39  that it is possible to increase the clamping force on the stitches so as to produce a knit with denser stitches. 
     FIG. 16 illustrates a detail of the guide parts of the yarn guide  10 , each of which comprises a free ring  10   e  held between two annular stops  10   d . This free ring  10   e  has a diameter which is substantially greater than that of the stem of the yarn guide  10 , but less than that of the two annular stops  10   d , such that it is free to move between these stops  10   d . By virtue of this arrangement, the yarn guide  10  may rotate with respect to the direction of the yarn  52 . Thus when the yarn guide  10  is transferred from one section to another by the transfer members  14 , it rotates through 180° but, by virtue of the free ring  10   e  which holds the yarn  52 , the rotation of the yarn guide  10  has no effect on the yarn  52  which may rotate with respect to the yarn guide  10  in order to retain the same orientation defined by the position of the coil supplying the yarn. 
     The embodiment of the knitting machine which has just been described is as follows: 
     In order to explain this operation, we are going to follow yarn guided by a yarn guide  10  from the moment where the latter is at the exit end of the guide groove  16  of the transfer member  14  which is located at the right-hand end of the section  1 , with reference to FIG.  1 . At the exit end of this guide groove  16 , this yarn guide is retained by the flap  16   a . When a sliding support  9 , pushed on the guide rail  8  by the pushers  12 ,  13  secured to the bracket  11  fastened to the carriage  4 , arrives directly above the exit of this guide groove  16 , it encounters the catching member  10   c  of the yarn guide  10  retained at the exit of this guide groove  16  by the flap  16   a . This catching member  10   c  enters through the front of the catching groove  9   a  until it stops against the pushers  12 ,  13  which drive the sliding support  9  along the guide rail  8 . From this moment, the yarn guide  10  advances with its yarn progressively with the movement of the carriage  4  with respect to the section  1 . 
     During its movement, the knitting cams (not shown) of the carriage  4  engage with the needles  3  which follow one another along the section  1 , thus making these needles, which knit the yarn which is presented to them by the yarn guide  10 , rise and fall. 
     When the yarn guide  10  arrives opposite the following transfer member  14 , that is to say, in the example chosen, the second of the four transfer members  14  starting from the one located at the right-hand end of the section  1  in FIG. 1, its guide portion  10   a  encounters the entrance of the guide groove  16  of this second transfer member. Simultaneously, the peg  13   a  encounters the cam  21   d  (FIG. 7) which withdraws the pusher  13  slightly rearward, thus releasing the rear end of the catching groove  9   a  of the sliding support  9 , only the pusher  12  remaining, by its sloped part  12   b , in contact with the yarn guide  10 . 
     Since the guide portion  10   a  of the yarn guide  10  is engaged in the guide groove  16  of the transfer member  14 , the yarn guide  10  changes direction, while the sliding support  9 , engaged with the rail  8 , continues to follow a path parallel to the section  1 . By virtue of its sloped face  13   b , the pusher  13  can thus give impetus to the yarn guide  10  as it exits from the catching groove  9   a  of the sliding support  9 , by the rear thereof. This impetus from the sloped face  12   b  of the pusher  12  has the effect of pushing the yarn guide  10  into the guide groove  16  of the transfer member  14 , until it stops against the retaining flap  16   a , where it waits to be taken up by another carriage  4  pushing another sliding support  9 . 
     As to the carriage  4  and to the sliding support  9 , which become separated from the yarn guide  10  engaged in the transfer member  14 , it continues its movement along the section  1  in the direction of the arrow F. Immediately after having left the second transfer member  14  from the right-hand end of the section  1  (FIG.  1 ), the sliding support  9  driven by the carriage  4  passes by the third transfer member  14 , rotates through 180° around the suspension member  15 , such that the path of the guide groove  9   a  of the sliding support  9  passes through the exit end of the guide groove  16  of the transfer member  14 , driving the yarn guide  10  waiting at this end into the passage. 
     The same knitting process as that described above takes place until the yarn guide  10  encounters the entrance of the guide groove  16  of the fourth transfer member  14  which is located at the left-hand end in FIG. 1 of the section  1 . Simultaneously, the cam  21   a  (FIG. 7) moves the pusher  13  away using the peg  13   a , and the sloped part  12   b  of the pusher  12  gives the yarn guide  10  impetus in order to transfer it toward the section  2 . 
     The carriage  4  then arrives at the left-hand end (FIG. 1) of the section  1  and it is now driven by the chain  5  toward section  2  by rotating around the disk  6 . As to the sliding support on the rail  8 , it approaches the widened part  8   a  of the guide rail  8 . At the start of this widened part, the pegs  12   a ,  13   a  of the pushers  12  and  13  encounter two cams  22   a  which withdraw these pushers  12  and  13  outward from the loop  8   a  in order to release the center therefrom and allow passage of the knitting yarn passing from the rotating yarn guide  32  to the yarn guides  10 . 
     Once the carriage  4  finishes its rotation, the pegs  12   a ,  13   a  encounter a cam  22   b  (FIG. 7) which returns the pushers  12  and  13  into their initial position, such that when the catching groove  9   a  of the sliding support  9  passes directly below the exit of the guide groove  16 , the catching member  10   c  of the yarn guide  10  is inserted in this catching groove  9   a  and is driven along the rail  8 , with the sliding support  9 , by the pushers  12  and  13 . 
     Given that the knitting yarn is transferred without cutting this yarn, from a knitting needle  3  bed of one of the sections  1 ,  2  to the knitting needle  3  bed of the other of these sections, while rotating constantly in the same direction, a tubular knit is formed and, as there are two pairs of transfer members  14  placed along the sections  1  and  2 , it is thus possible to form two tubular knit elements side by side, which may advantageously constitute the two legs of a seamless pair of pants, boxer shorts or tights. Once the length of the legs is reached, it is enough to select the knitting needles  3  which are between the two transfer members  14 , using conventional selection means which are not shown because they are not part of the present invention. 
     At the same time as the aforementioned knitting needles  3  are selected, the two transfer members  14  are rotated through 90° using motors  17 , such that the yarn guides  10  can no longer engage in the guide grooves  16  and that only the transfer members  14  placed at the two ends of the sections  1 ,  2  are still in service. Hence, the two tubular knit elements forming the legs of the pair of pants, the boxer shorts or the tights are joined into a single tubular element forming the top of the pair of pants, boxer shorts or tights. Simultaneously, given that, from this moment, each knitting yarn makes a complete rotation of the sections over their entire width rather than only over half of this width, the geared drive motors M will drive the creels  24  at half speed. 
     Given that the speed at which the carriages  4  are driven by the endless drive chain  5  is constant, the servomotors  35  associated with each carriage  4  make it possible to reduce or increase the rate of movement of these carriages  4  in order to make it possible to synchronize them. This is because, in the example described, each creel  24  bears four reels  23  supplying knitting yarn, which corresponds to four yarns per knitted leg and to eight yarns when knitting the top of the pair of pants. Given the increases and decreases in the width of the knit, it may be necessary to modify the speed of the carriages  4  in order to take the yarn guides  10  to the exit of the transfer members  14 . 
     However, before the carriage  4  starts to rotate around the drive disks  6  in order to operate with the opposite section, the servomotor  35  must put the carriage  4  back into the zero position, that is to say, in the position where it is neither advanced or retarded with respect to the reference spacing between the carriages  4 . 
     When the knitting needles  3  are selected for the purpose of increasing or reducing the diameter of the tubular knitted element or elements, it is necessary to change the positions of the transfer members  14  so that they follow these changes in diameter. This adjustment is carried out by the worm  19  and the stepper motor  20 . Since the threads of the various portions  19   a ,  19   b ,  19   c ,  19   d  of the worm are reversed, when the two legs of the pants are knitted, depending on the direction of the rotation of the worm  19 , the paired transfer members  14  defining the two legs of the pants come together or move apart from each other. Similarly, when knitting a single tubular element forming the top of the pair of pants, where the two transfer members  14  located in the middle part of the sections  1 ,  2  are taken out of service, as explained above, the two transfer members  14  located at the ends of these sections  1 ,  2  come together or move apart from each other depending on the direction of rotation of the adjustment screw  19 . 
     In a variant illustrated in FIG. 17, to prevent the yarn  52  winding around the rotating yarn guide, when the latter follows the tubular shape of the knit and thus changes orientation with respect to the portion of yarn located between the movable yarn guide  10  and the yarn guide  32 , it is also possible to use a tubular yarn guide  10 ′. The yarn  52  enters by one end of the tube of the yarn guide  10 ′ and exits by the other end. 
     Such a yarn guide  10 ′ may therefore change orientation with respect to the stationary yarn guide  32  without the yarn becoming wound around it. Such a yarn guide  10 ′ may advantageously comprise two disks  10 ′ f  and  10 ′ g , one  10 ′ f  serving to support the yarn guide  10 ′ on a carriage (not shown) and the other to engage with a transfer arm (not shown). 
     The second embodiment will now be described with reference to FIGS. 9 to  15 . Several of the changes described in relation to this embodiment may be used in the previous embodiment. Similarly, several of the elements described with respect to the first embodiment may be used in the second embodiment. 
     The fundamental difference between these two embodiments resides in the fact that, instead of moving in a horizontal plane, the carriages  40  in the second embodiment move in two vertical planes, such that this embodiment requires twice as many carriages as the first embodiment. Another noticeable difference is seen in the creels for the reels supplying knitting yarn. 
     FIG. 9 shows an endless drive chain  41  forming a closed loop around two wheels  42  with horizontal pivot pins. A second identical chain forms a second parallel loop, placed on the other side of the two vertical sections  43 ,  44 , as can be seen in particular in FIG.  10 . The carriages  40  are each connected to one of the chains  41  by a pin  40   a  transverse to this chain, enabling them to pivot. Each of these carriages  40  also bears two guide pegs  40   b , intended to engage with two guide rails  45  placed at the two ends of the closed loop described by the carriages  40 . These carriages  40  therefore have three guide points, the pin  40   a  and the pegs  40   b , such that, by virtue of the guide rails  45 , they can move from the upper horizontal part of their path to the lower horizontal part, while constantly remaining in a horizontal position both when going from the top downward of their path and from the bottom upward. 
     Unlike the previous embodiment where the transfer of the yarn from one section to the other is carried out by transferring the yarn guides, in this embodiment, only the yarn is transferred, the yarn guides  46  being secured to the carriages  40 . As illustrated in FIGS. 13,  13   a , and  14 , the yarn guide  46  is fastened to the carriage  40  by a post  47  around which a tubular body  48  pivots. This tubular body  48  is terminated by a pinion  49  at its lower end and by a yarn retaining element  50  consisting of a member provided with four radial notches  50   a  reminiscent of a Maltese cross, at its upper end. The pinion  49  engages with a take-off  49   a  mounted so that it can pivot on the carriage  40 . The upper end of the post  47  bears a member  51  for locking the knitting yarn  52 . This locking member  51  is mounted so that it can pivot on this post  47  and is normally applied against a stop  53  secured to an arm  53   a  itself secured to the post  47 . A return spring  54  tends constantly to keep the locking member applied against the stop  53 . 
     There are four transfer stations  55  (FIGS. 12,  13 ,  14  and  15 ), equivalent to the transfer members  14  of the first embodiment, so that the knitting yarn can be transferred from one section to the other, at each end of the knitting travel, corresponding to half a portion of tubular knit. The two transfer stations  55  located in the middle part of the sections can be taken out of service to allow the top of the pair of pants to be knitted. As with the transfer members  14 , the transfer members  55  of the second embodiment are engaged with adjustment screws  19 ′,  19 ″, controlled by motors  20 ′,  20 ″, in order to vary the width of the knit. 
     Each transfer station  55  comprises two racks  56  located on the respective paths of two take-offs  49   a . A release cam  57  is again placed on the path of a portion  51   a  of the member  51  for locking the knitting yarn  52 , on the side where this yarn must be released from the yarn guide  46  in order to be transferred to the other section. In the example described, this release cam  57  is located to the left with reference to FIG.  13 . 
     The frame of this transfer station  55  also comprises two transfer slides  58 ,  59 , each one bearing two stops  58   a ,  59   a , respectively, intended to limit their respective travels. Two actuating members  60  serve to actuate these slides from one stop to the other and vice versa. The free end of the transfer slide  58  is also secured to a pusher  58   b  fitted with an opening for passage of the other slide  59 . The pusher  58   b  may be moved by the transfer slide  58  up to a stop surface  55   a  secured to the frame of the transfer station  55 . 
     FIGS. 9 to  11  show another creel device intended to supply the knitting yarns by making them rotate always in the same direction, in this case, clockwise (FIG.  11 ), and by allowing the knitting yarns to rotate around the two respective rotating pins while knitting the legs of the pants, then around a single pin when knitting the top of the pair of pants. 
     This creel device comprises vertical reel supports  61 , each one of which bears a reel  62  of knitting yarn  52 . Each vertical support  61  rests on a support surface  63  while it is guided upward by a guide rail  64 . This guide rail forms, as illustrated in FIG. 11, two small oval loops included within a large oval loop. The two small oval loops are intended to guide the reel supports  61  when knitting the trouser legs, while the large loop is intended to guide them when knitting the top of the pair of pants. 
     Each vertical support  61  comprises a connection member  65 , mounted so that it can slide in a vertical groove  66  (FIG.  9 ). A slide  67  secured by guide pegs  67   a  engaged with guide grooves  67   b  and actuated by a crank mechanism  82 , serves to move the connection member  65  in this vertical groove  66 . 
     The inner end of this connecting member  65  is shaped so as to engage selectively with flexible drive members  68 ,  69 ,  70  (FIGS. 9,  10 ), forming three endless loops, like the guide rail  64 , while passing round wheels  71  pivoted around vertical pins  72 ,  73 ,  74 ,  75 . The pin  72  is connected to a geared motor  76  also connected to one of the wheels  42  for guiding and driving the chain  41 . This geared motor  76  makes it possible to vary the drive speed of the pin  72 , depending on whether the supports  61  rotate along the two small loops of the guide rail  64  or along the large loop, that is to say, whether they are engaged with the drive members  68 ,  69  or with the drive member  70 . 
     As in the previous embodiment, the carriages  40  are connected to the drive chains  41  by a servocontrol system as illustrated in FIG. 8, making it possible to vary the speed of the carriages with respect to that of the drive chains  41 . 
     To explain the operation of this second embodiment, we will start with a carriage  40  moving in the direction of the arrow F 1  (FIG. 12) and arriving at the transfer station  55  which is located toward the left-hand end of the sections  43 ,  44 . This part of the knitting machine is illustrated in more detail in FIGS. 13 and 14 to which reference may be made. The carriage  40 , which moves in the direction of the arrow F 1 , bearing the yarn guide  46  which drives the knitting yarn  52 , is at the point of arriving at the transfer station  55 , while the carriage  40  which is moving in the direction of the arrow F 2  bearing the yarn guide  46  empty of knitting yarn also arrives at the transfer station  55 . 
     On arriving at this transfer station  55 , the take-off  49   a  of the yarn guide  46  moving in the direction of the arrow F 1  encounters the rack  56  which makes the yarn retaining member  50  rotate in the direction of the arrow F 3  (FIG. 13 a ). Virtually simultaneously, the part  51   a  of the locking member  51  of the knitting yarn  52  (FIGS. 13,  14 ) encounters the cam  57  which makes this locking member  51  rotate counter to the tensile force of the spring  54 , such that the locking member  51  rotates in the direction of the arrow F 3  (FIG. 13 a ), releasing the radial notch  50   a  and thus freeing the knitting yarn  52 . 
     As soon as it is freed, the knitting yarn  52  is then moved by the pusher  58   b  against the stop surface  55   a  and the slide  59  closes the space in which the knitting yarn is enclosed, as is shown in dotted line in FIG.  14 . The yarn is then positioned to be taken into a radial groove  50   a  of the yarn retaining member  50  which is moved in the direction of the arrow F 2 , as illustrated in FIG.  14 . Virtually simultaneously, the rack  56  encounters the take-off  49   a  which makes the retaining member  50  of the knitting yarn  52  rotate through 90° in the direction of the arrow F 3 , which is locked by the locking member  51 . 
     The same transfer operation is then carried out in the reverse direction when the carriage  40 , which moves in the direction of the arrow F 2 , has reached the transfer station  55 ′, which is located in the middle part of sections  43 ,  44 . The transfer station  55 ′ differs from the station  55  of FIG. 14 only in that, in order to transfer the knitting yarn  52  from the section  44  to the section  43 , it is the slide  59 ′ with an arm  59 ′ b  at 90° which must take the yarn  52 ′ from right to left instead of pushing it from left to right as the pusher  58   b  of FIG. 14 does. The rest of the operations are the same such that reference may be made to FIG.  14 . 
     Symmetrical operations are carried out on the knitting yarns, knitted on the right half of the sections  43 ,  44 . When the legs of the pants or tights are completed and when it is necessary to pass to the top of the pair of pants, the two transfer stations  55 ,  55 ′ located in the middle of the sections  43 ,  44  are taken out of service and the knitting yarns  52  are transferred only at the two ends of the sections  43 ,  44 . 
     The reels  62  are moved on the creel by following the movement of the yarn guides  46  driven by the carriages  40 . When knitting the trouser legs, the connection members  65  of the supports  61  for reels  62  are connected to the flexible drive members  67 ,  68 , respectively, and are guided along the two small elongated loops formed by the guide rail  64 . When the top of the pair of pants are knitted, the connection members  65  are connected to the flexible drive member  70  by the actuating members  67  and then describe a single elongated path. 
     In the two embodiments described above, each section is made as a single part. In a variant (not shown), it would be possible to use sections in two parts capable of being moved laterally one with respect to the other according to a system known in rectilinear knitting machines. By virtue of this type of section, after having knitted the two tubular parts, the two section parts could be joined to knit the common tubular part, corresponding to the top of the pair of pants.

Technology Classification (CPC): 3