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EP-4399359-B1 - CIRCULAR KNITTING MACHINE AND METHOD FOR REVERSING A TUBULAR KNITTED ITEM

EP4399359B1EP 4399359 B1EP4399359 B1EP 4399359B1EP-4399359-B1

Inventors

  • LONATI, ETTORE
  • LONATI, FAUSTO
  • LONATI, FRANCESCO

Dates

Publication Date
20260513
Application Date
20220823

Claims (12)

  1. A circular knitting machine for hosiery (1), comprising at least one needle cylinder (2) which has a cylinder axis (100) and is configured to provide a tubular item (101), said circular machine (1) comprising a pickup device (10) which is adapted to pass between a pickup position, in which it is arranged coaxially around said needle cylinder (2) in order to pick up said tubular item (101) at a first axial end thereof (101a) from said needle cylinder (2), and a position for the release of said tubular item (101) at a station for further processing (40) of said tubular item (101) which is laterally spaced apart from said needle cylinder (2), at said further processing station (40) there being a turning device (20) which comprises a lower portion (22) having at an upper region an access mouth (21), which extends around a respective axis of extension (103), and an upper portion (25), which are arranged respectively below and above an intermediate region at which supporting means (41) for supporting the tubular item (101) to be turned, which hangs to the pickup device (10) at said first axial end (101a), are or can be positioned, said lower portion (22) of said turning device (20) being designed to accommodate coaxially said tubular item (101) in order to perform its turning, and being movable between a first position, in which said access mouth (21) is aligned with said upper portion (25) in order to allow the turning of said tubular item (101), and a second position, in which said access mouth (21) is arranged laterally with respect to said upper portion (25) in order to allow the transfer of said tubular item (101) from said needle cylinder (2) into said lower portion (22) of said turning device (20), and said lower portion (22) of said turning device (20) is inclined on command about a pivoting axis (110) in order to pass from said first position to said second position and vice versa, and the circular knitting machine being characterized in that it comprises a lifting element (50) which is adapted to pass between an inactive condition, in which it is arranged externally with respect to the region affected by the movement of said pickup device (10) and of the corresponding tubular item (101) associated therewith during the transition of said lower portion (22) from said second position to said first position, and an active position, in which said lifting element (50) is adapted to interact with at least one portion of said tubular item (101), in said active position said lifting element (50) being movable on command along a lifting trajectory (200) in order to engage with said portion of said tubular item (101) so as to determine the disengagement of the second axial end (101b) of said tubular item (101), opposite to said first axial end (101a), from the needle cylinder (2) and the conveyance of said second axial end (101b) of said tubular item to said access mouth (21) when said lower portion (22) is in said second position.
  2. The circular machine (1) according to claim 1, characterized in that said turning device (20) is associated with suction means adapted to transfer said tubular item (101) conveyed to said access mouth (21) into said lower portion (22) of said turning device (20).
  3. The circular machine (1) according to one or more of the preceding claims, characterized in that said lifting trajectory (200) has a substantially vertical extension.
  4. The circular machine (1) according to one or more of the preceding claims, characterized in that said lifting element (50) is configured for engaging said tubular item (101) at an intermediate portion between said first axial end (101a) and said second axial end (101b).
  5. The circular machine (1) according to one or more of the preceding claims, characterized in that said lifting element (50) comprises a U-shaped engagement body (51).
  6. The circular machine (1) according to one or more of the preceding claims, characterized in that said lifting element (50) comprises at least one contact element (52) configured to make contact with said tubular item (101) and to reduce the sliding friction between said lifting element (50) and said tubular item (101).
  7. The circular machine (1) according to claim 6, characterized in that said contact element (52) comprises a plurality of annular bodies (52a) which are coupled rotatably to said engagement body (51).
  8. The circular machine (1) according to one or more of the preceding claims, characterized in that said turning device (20) comprises a tubular body (23) which can be inserted from below toward the upper part of said lower portion (21), with its upper axial end, through said axial end of the tubular item (101) which hangs from said supporting means (41) after suction of the item through said upper axial end of the tubular body, for the eversion of the item, retained by said supporting means (41).
  9. The circular machine (1) according to one or more of the preceding claims, characterized in that said tubular body (23) can move on command with said lower portion (22) in said second position in order to pass from a retracted position, in which it is accommodated within said lower portion (22), to an extended position, in which it protrudes from the access mouth (21) in order to be moved below said second end portion (101b) of said tubular item (101) lifted by said lifting element (50).
  10. A method for reversing a tubular knitted item (101), comprising the steps of: - producing, using at least one needle cylinder (2), a tubular item (101); - picking up, using a pickup device (10), said tubular item (101) at a first axial end (101a); - transferring said first axial end (101a) of the tubular item (101) from a pickup position, at said needle cylinder (2), to a release position at a further processing station (40) of said tubular item (101); - moving a lifting element (50) from an inactive position, in which it is arranged externally with respect to the region affected by the movement of said pickup device (10) and of the corresponding tubular item (101) associated therewith during the transition of said lower portion (22) from said second position to said first position, to an active position, in which said lifting element (50) is adapted to interact with at least one portion of said tubular item (101); - lifting said lifting element (50) to said active position along a lifting trajectory (200) in order to engage with a portion of said tubular item (101) so as to determine the disengagement of the second axial end (101b) of said tubular item (101), opposite to said first axial end (101a), from said needle cylinder (2); - moving a lower portion (22) of a turning device (20) which has an access mouth (21) between a first position, in which said access mouth (21) is aligned with an upper portion (25) of said turning device (20) in order to allow the turning of said tubular item (101), and a second position, in which said access mouth (21) is arranged laterally with respect to said upper portion (25) and substantially below said second axial end (101b) of said tubular item (101) in order to allow the transfer of said tubular item (101) from said needle cylinder (2) into said lower portion (22) of said turning device (20) wherein said lower portion (22) of said turning device (20) is inclined about a pivoting axis (110) in order to pass from said first position to said second position; - aspirating, using suction means, of said tubular item (101) in order to transfer it, through said access mouth (21), to said lower portion (22) of said turning device (20); - moving said lifting element (50) from said active position to said inactive position; - moving said lower portion (22) from said second position to said first position.
  11. The method according to claim 10, characterized in that it comprises, after said step of moving said lower portion (22) from said second position to said first position, a step of turning said tubular item using said turning device (20).
  12. The method according to one or more of claims 10 to 11, characterized in that it comprises, between said step of moving said lower portion (22) between said first position and said second position and said step of aspiration, at least one further step of lifting said lifting element (50) along said lifting trajectory (200).

Description

The present invention relates to a circular knitting machine for hosiery or the like and a method for providing a tubular item. In the sector of production of knitted tubular items with circular knitting machines for hosiery or the like, in some cases there is the need to perform a transfer of the item from the machine used for the production of the item to another production unit in order to perform further work on the item that cannot be performed on such machine or which it is not economically convenient to perform on such machine. In particular, in the sector of production of hosiery items, in recent years, techniques for automatically closing the toe thereof, by sewing or linking, have been developed. Some of these techniques are based on the removal of the item from the machine used for its production and on its transfer to a station for further processing, separate from the production machine, so as to close the toe of the hosiery item in the station for further processing while the machine is used to produce another hosiery item. These techniques have the advantage, with respect to other techniques that are based on closing the toe of the hosiery item directly on the machine used for its production, of not excessively penalizing the productivity of the machine. The transfer of the hosiery item, or more generally of the tubular item, from the machine used for its production to the station at which the closing of an axial end of the item, or more generally further processing on the item, must be performed is generally performed by means of a pickup device which, using pickup elements, individually picks up the loops of knitting of the item from the needles of the machine and holds them during the transfer of the item. In some techniques for closing the toe of hosiery items, the pickup device is also used to support the item during the execution of the further processing, while in other techniques the pickup device is used only to transfer the item since, once it has arrived at the station in which the further processing is to be performed, it releases, usually again individually, the loops of knitting, which were previously removed from the needles, to another device whose function is to support the item during the execution of the further processing, such as for example a handling device. In both techniques, the sewing or linking operation is very often carried out on the item in the inside-out configuration so that the sewing or linking chain is not easily visible on the external side of the item and that is to say on the side that, usually, is visible with the article being worn. For this reason, in sewing or linking stations intended to implement these techniques for closing one axial end of knitted tubular items, a turning device is generally provided the function of which is to perform the inversion of the item, which is taken in the right-way-out configuration from the machine that produced it, before subjecting it to the sewing or linking operation and optionally inverting it again in order to bring it to the right-way-out configuration after the sewing or linking operation. One of the most widespread types of turning devices for this type of use is based on using a tubular body which, from below, faces the item, which is held by a pickup device or by a handling device at its axial end to be closed and is arranged substantially vertically with such axial end directed upward. The tubular body is also arranged with its axis vertical, so as to face the hung item with its upper axial end. The inside of the tubular body is therefore connected to suction means so as to suck, through its upper axial end, the item which however remains retained, at its axial end to be closed, by the pickup device or by the handling device. The tubular body is then lifted so that its upper axial end passes through the axial end of the item which is engaged with the pickup device or with the handling device. As a consequence of this passing through, the item is everted on the outer lateral surface of the tubular body and is extracted progressively from the upper axial end of the tubular body by carrying out its turning. For tubular items of considerable weight, such as for example for hosiery items of great thickness and/or considerable weight, difficulties can be encountered in successfully ensuring a correct insertion of the tubular item inside the tubular body. EP2250307B1 discloses the preamble of claim 1 and a method for reversing a tubular knitted item comprising moving a lower portion of a turning device which has an access mouth between a first position, in which said access mouth is aligned with an upper portion of said turning device in order to allow the turning of said tubular item, and a second position, in which said access mouth is arranged laterally with respect to said upper portion and substantially below said second axial end of said tubular item in order to allow the transfer of said tubular item fro