Abstract:
The present invention pertains to a circular knitting machine with a pair of cutting devices (15) in opposite positions for longitudinally cutting, on two sides, the tubular fabric component and for forming two individual even pieces (13a, 13b) and with two winding units (11, 12) for separately winding the two pieces onto rolls, the pieces being led in opposite directions by central return rollers (16, 17).

Description:
FIELD OF THE INVENTION 
     The present invention concerns the field of circular knitting machines and specifically pertains to a winding unit for the winding on a roll of the fabric produced on such machines. 
     BACKGROUND OF THE INVENTION 
     From the knitting process oil circular machines there is obtained, as is known, a fabric component having a tubular shape which is led and progressively wound onto a winding roller arranged in the lower part of tlie machine. However, it is well known to persons skilled in the art that with the winding onto the winding roller of the tubular fabric, two folds are inevitably formed along two generators on opposite sides of the tubular component and produce an opposite effect during treatments, processing and subsequent use of tile fabric. Even when the tubular fabric component is being cut along its generator, the problem is only partially resolved since, with the winding of the fabric component onto a winding roller, even if open on one side, a longitudinal fold is always formed, however, on the other side of the fabric. 
     SUMMARY AND OBJECTS OF THE INVENTION 
     On the contrary, the object of the present invention is to solve such a problem in a new and original manner with the unquestionable advantage of eliminating the formation folds on the fabric due to winding in such a way as to provide even pieces or lengths of fabric capable of being used more easily and comfortably. 
     The solution to the problem is achieved by longitudinally cutting, on two opposite parts, the tubular fabric component as produced on a circular knitting machine, so as to form two individual even pieces, and by winding the pieces or lengths of fabric on two separate winding units. 
     Therefore, the circular machine is provided, not with only one winding unit as usual, but with two piece-winding units which are arranged in parallel and with two cutting devices in opposite positions. The two piece-winding units are operated contemporaneously by a single control drive for rotating in opposite directions and winding the two pieces, the one in the opposite direction of the other. Thus, the surface of the knitted fabric which is facing the inside of the starting component is turned towards the center of the roll which is formed on each winding unit. 
     Since the edges of each piece produced from the longitudinal cuts of the tubular component have the tendency to be rolled up or curled up, each winding unit also comprises a stretching roller intended for stretching out or drawing the edges and smoothing out the piece for its correct winding. The stretching roller is arranged in parallel to the corresponding winding roller and is operated by a control drive derived from that which operates the winding roller. 
     It must be noted that tile adoption of two piece-winding units on a circular knitting machine does not change in any way, however, the structure and the operation of the machine. In other words, the machine can be equipped either in the traditional manner with only one winding unit or with two winding units in accordance with the present invention. 
     Each piece wound on the winding rollers shall have a width equal to half the circumference of the starting tubular component. In order to obtain pieces of suitable width, at least equal to that of a piece produced by the opening of a cut tubular component, as usual, along only one generator, it is possible start with a machine having a greater diameter, that is, double. This is not a disadvantage since from such a machine are produced two pieces having a width equal to the generation of a tubular component produced on a very small machine, especially already cut and advantageously without folds. 
     The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings: 
     FIG. 1 shows schematically the two winding units and pertinent controls; 
     FIG. 2 shows in perspective view part of one of the winding units with guides for the winding roller; 
     FIG. 3 shows a lateral view of the units applied to the base of a circular machine; and 
     FIG. 4 shows schematically the arrangement for the unloading of a roll of fabric from the machine. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the drawings, part of the base of a circular knitting machine is indicated as 10, and the two winding units, which are arranged symmetrically and applied on opposite sides of the base, are indicated as 11 and 12. 
     The knitted tubular component 13 produced on the circular machine or knitting means is set into motion by means of guide or transport rollers 14, one of which 14a is operated by a drive (not shown) derived from that which operates the cylinder of the machine. The tubular component 13 is cut longitudinally on opposite sides by means of cutters 15, provided with a sharpener. The cutters 15 are located at the base of the machine under the guide rollers 14 and in a position centered between the two winding units. After cutting, the tubular component 13 is divided into two pieces or lengths of fabric 13a, 13b which are guided and directed in opposite directions, by means of central return rollers 16, 17, to the winding units 11, 12, respectively. 
     Each winding unit 11, 12 comprises a winding roller 18 controlled in rotation, with friction, by a pair of guiding rollers 19, 20. As shown in FIG. 1, the winding roller 18 rests, due to gravity, on the complanate guiding rollers 19, 20 across the wound-up piece. Moreover, the winding roller 18 has end necks--cf. FIGS. 2 and 4--each arranged between two vertical outer and inner guide gibs 21, 22 which make it possible to raise the roller for increasing the diameter of tile piece roll which is being wound up. 
     The guiding rollers 19, 20 of both winding units 11, 12, as well as the central return rollers 16, 17, are operated simultaneously by a control drive 23, for example, a chain drive, which leads to the movement of the above-mentioned roller 14a. The drive 23 is such that it rotates the winding rollers 18 in opposite directions so as to wind the pieces or lengths of fabric 13a, 13b in opposite directions and with the inside surface of the pieces, or lengths of fabric, coming from the machine being turned towards, or wound on, the center of the roll. 
     On the inlet side in each winding unit of pieces 13a and 13b, a stretching roller 24, of the type with two opposite screws or screw surfaces, is coupled in parallel to the winding roller 18 for stretching out and drawing the edges of the piece which tend to be rolled up immediately before the piece 13a or 13b is wound onto the roller 18. The stretching roller 24 is operated in rotation by a drive 25, for example, a chain drive, controlled by the adjacent guiding roller 19 with an appropriate ratio. Basically therefore, the knitting tubular component 13 is longitudinally cut on two sides so as to form two pieces 13a, 13b. The two pieces are led separately and wound progressively onto two winding rollers 18 after being passed onto the stretching roller 24. 
     The vertical guide gib 21, at the neck of each winding roller is arranged towards the outside of the machine. This gib 21 is pivoted toward the bottom at 21a and blocked in the vertical position by means of a releasable means 22a. Because of this, the gibs 21 can be released and folded on one side--cf. FIG. 4--to form an inclined plane which aids the unloading of the fabric roll once completed. 
     If, as usually occurs, the unloading of the fabric on the roll is provided on only one side of the machine, the winding units can be mounted oil a rotating platform 26--cf. FIG. 3. This allows the machine to be able to support one roll after the other in correspondence to the only unloading outlet and emptying the machine by making use of the inclined planes which are produced by folding the guide gibs 21. 
     While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.