JP2024520582A - Circular knitting machine for hosiery or the like, and method for producing tubular products - Google Patents

Abstract

A circular knitting machine with a needle cylinder configured to produce a tubular product includes a pick-up device that reciprocates between a pick-up position arranged coaxially around the needle cylinder for picking up the tubular product and a position for releasing it at a station laterally spaced from the needle cylinder. The station is provided with an everter having a lower part forming an access entrance. The lower part of the everter is configured to coaxially receive the tubular product for turning it inside out. The circular knitting machine includes a pulling means adapted to act on an outer surface of the tubular product in command to convey a portion of the tubular product to a storage area. The everter is associated with a suction means to transfer a portion of the tubular product conveyed to the storage area through the access entrance towards the lower part of the everter.

Description

The present invention relates to a circular knitting machine for hosiery and the like, and a method for producing tubular products.

In the field of manufacturing tubular knitted products using circular knitting machines for hosiery and the like, it is sometimes necessary to transfer the product from the knitting machine to a separate manufacturing unit for further processing of the product that cannot be performed on the knitting machine used to manufacture the product or that is not economically advantageous to perform on the knitting machine.

In particular in the field of hosiery production, techniques have been developed in recent years for automatically closing the toe of a hosiery product by a series of stitches or looping. Some of these techniques are based on removing the product from the knitting machine and transferring it to a station for further processing away from the producing knitting machine, so that the toe of the hosiery product is closed at the station for further processing, while the knitting machine used to produce the hosiery product is used to produce another hosiery product. These techniques have the advantage over other techniques based on directly closing the toe of the hosiery product on the knitting machine used to produce the hosiery product, that they do not impair the productivity of the knitting machine to a great extent.

The transfer of a hosiery product, or more generally a tubular product, from a knitting machine used to manufacture such a product to a station for closing the axial ends of the product, or more generally for further processing of the product, is typically performed by a pick-up device in which pick-up elements individually grip the knitted loops of the product from the needles of the knitting machine and hold these knitted loops during the transfer of the product.

In some techniques for closing the toe of hosiery products, the pick-up device is further used to support the product while further processing is being carried out, while in other techniques the pick-up device is used only to transfer the product, as when it reaches the station where further processing is carried out it usually transfers the knitting loops already picked up from the needles again separately to another device, e.g. a processing device, which has the function of supporting the product while further processing is being carried out.

In both of these techniques, the sewing or looping action is often performed inside out relative to the product so that the stitching or looping chain is largely invisible on the face of the product, i.e., the side that would normally be visible when the product is worn.

For this reason, sewing or looping stations configured to perform these techniques to close the axial ends of tubular knitted products are typically provided with a flipping device that functions to flip the product picked up with the product facing out from the knitting machine that produced the product before performing the sewing or looping operation on the product, and optionally to flip the product again after the sewing or looping operation to return the product to a facing out state.

One of the most widespread types of turn-over devices for this type of use is based on the use of a tubular body, which is supported by a pick-up or processing device at the axial end of the product to be closed and is positioned substantially vertically with said axial end facing upwards in the lower area. The tubular body is further arranged so that its upper axial end is vertical so as to face the suspended product. The interior of the tubular body is therefore connected to a suction means so as to suck in, via the upper axial end, the product that remains held by the pick-up or processing device at the axial end to be closed. The tubular body is therefore raised so that its upper axial end crosses the axial end of the product engaged by the pick-up or processing device. This crossing causes the product to be turned over on the outer surface of the tubular body and gradually removes the product from the upper axial end of the tubular body as it is being turned over.

In the case of heavy tubular products, for example thick and/or long hosiery products, it may be difficult to reliably and accurately insert the tubular product into the tubular body.

The object of the present invention is to solve the above-mentioned problems by providing a circular knitting machine for hosiery and the like, which reliably and accurately inserts tubular products into tubular bodies, even when the tubular products are of considerable weight and length.

Within this spirit, the object of the present invention is to provide a circular knitting machine for hosiery and the like, which has high reliability and precision of operation.

Another object of the present invention is to provide a circular knitting machine for hosiery and the like that is structurally simple and can be offered at a competitive price.

This aim, as well as these and other objects which will become more apparent hereinafter, are achieved by a circular knitting machine for hosiery or the like and a method for manufacturing tubular products according to the independent claims, optionally having one or more of the features of the dependent claims.

Further features and advantages of the present invention will become more apparent from the description of preferred, but not exclusive, embodiments of a circular knitting machine for hosiery or the like according to the present invention, shown in the accompanying drawings, which are non-limiting examples.

1 is a plan view showing a knitting machine according to the present invention. FIG. 2 is an enlarged view of a tensioning device for a circular knitting machine according to the present invention; 1 is a schematic front view of a circular knitting machine in which a pick-up device is arranged coaxially with respect to the needle cylinder and in a pick-up position in the upper region. 4 is a view similar to FIG. 3, but with the pick-up device in an intermediate position between the pick-up position and the release position. FIG. 2 is a view similar to the previous one, in which the pick-up device is arranged in a further processing station in a release position; FIG. 6 is a view similar to FIG. 5 during the preparation step of the tensioning device. 7 is a view similar to FIG. 6 during the actuation process of the tensioning device. 8 is a view similar to FIG. 7 during the operating process of the suction device. 1 is a schematic front view showing the knitting machine ready to turn the tubular product inside out.

With reference to the drawings, a circular knitting machine for hosiery or the like according to the present invention, generally designated by the reference numeral 1, includes at least one needle cylinder 2 having a cylinder axis 100 and configured to produce a tubular product 101.

Advantageously, the circular knitting machine 1 can be a double cylinder circular knitting machine or a hosiery knitting machine, as shown in the drawings.

Naturally, nothing herein prevents the application of the inventive concept that is the subject of this application to single-cylinder circular knitting machines.

Advantageously, the circular knitting machine 1 comprises a lower needle cylinder with a vertically oriented axis 100 and an upper needle cylinder arranged in an upper region coaxially with the lower needle cylinder. The needle cylinder is provided with a number of axial grooves on its side, each of which accommodates a needle, and the needles are operable in a reciprocating motion along the corresponding axial groove to form the knitted product.

The lower needle cylinder and the upper needle cylinder have therein, in a manner known per se, an ejection device for ejecting the product. By way of example, the ejection device has a tubular suction element coaxial with the needle cylinder. This tubular suction element is movable along an axis 100 relative to the lower needle cylinder so that it can protrude with a part of its extension from the upper end of the needle cylinder 2.

The needles are actuated in a manner known per se, for example by cams, not shown for the sake of simplicity, arranged around the needle cylinder, which can engage with the heels of the needles which project radially from the sides of the needle cylinder as a result of the latter rotating about its own axis 100 relative to said cam. The circular knitting machine 1, which is essentially a knitting machine of known type, is not described further for the sake of simplicity.

The circular knitting machine 1 is equipped with a pick-up device 10 adapted to shuttle between a pick-up position arranged coaxially around one or more needle cylinders 2 for picking up the tubular product 101 from the needle cylinders at their axial ends, and a position spaced laterally from the needle cylinders 2 for releasing the tubular product 101 at a station 40 for further processing of the tubular product 101.

The further processing station 40 preferably comprises a sawing or looping station.

By way of example, the pick-up device 10 has an annular pick-up body 11, which supports pick-up elements that are radially slidable relative to the pick-up body 11. The pick-up body 11 can be arranged coaxially around the needle cylinder 2 such that the pick-up elements laterally face corresponding needles of the circular knitting machine 1, respectively.

The pick-up device 10 has actuation means acting on the pick-up elements to move them towards or away from the axis of the pick-up body so as to engage or disengage each pick-up element from the opposing needle, each pick-up element being adapted to pick up a knitted loop of the product 101 held by the needle.

Of course, nothing prevents the provision of pick-up elements to engage between the knitted loops if non-loop sewing is subsequently performed.

More specifically, the pick-up body 11 is arranged with its axis vertical and is fixed to the end of the arm 12, which is arranged horizontally. The arm 12 is connected at its opposite end to a sleeve having a vertical axis 102. The sleeve is coaxially fitted around the hollow shaft and is integral with it during rotation about its axis. The hollow shaft is supported by a support structure for rotation about its axis 102, which may be constituted by the support structure of the knitting machine 1 itself or by an autonomous support structure that may be optionally associated with the support structure of the knitting machine 1.

It is preferable that the rotation of the arm 12 can be stopped at at least one standby position or intermediate position provided between the above-mentioned pick-up position and release position.

The two or three positions that the pick-up body 11 can take after the activation of a motor means constituted, for example, by an electric motor, are controlled by respective sensors which detect references arranged on each part during their relative movement.

The circular knitting machine 1 is provided with a turning device 20 having a lower part 22 forming an access opening 21 in the upper region in a further processing station 40.

The lower portion 22 of the turning device 20 extends about its elongated axis 103 and is configured to coaxially receive the tubular product 101 for turning it over.

The circular knitting machine 1 according to the present invention is provided with a tensioning means 30 which acts on the outer surface of the tubular product 101 in a command manner.

The pulling means 30 is adapted to convey at least one portion of the tubular product 101 to at least one accumulation area 200.

The lower part 22 of the turning device 20 is associated with suction means adapted to transfer at least one portion of the tubular products 101 conveyed to the accumulation area 200 towards the lower part 22 of the turning device 20 via the access inlet 21.

Advantageously, the accumulation area 200 is located immediately adjacent to the access entrance 21.

The pulling means 30 is configured to remove at least one portion of the tubular product 101 toward an end opposite the end associated with the pick-up device 10.

The turning-over device 20 has an upper part (not shown) in addition to the lower part 22, which are advantageously arranged below and above, respectively, an intermediate area in which a support means 41 for the turning-over tubular product 101 suspended at the axial end of the tubular product 101 is arranged or can be arranged.

The turning-over device 20 further has a tubular body 23, which can be inserted at its upper axial end from below upward through the axial end of the tubular product 101 suspended from the support means 41 after sucking the tubular product through the upper axial end of the tubular body in order to turn over the tubular product held by the support means 41.

With reference to the embodiment shown in the drawings, the tensioning means 30 comprises at least one pull roller 32 associated with a motor means 35.

The pull-out rollers 32 are advantageously positioned immediately adjacent to the storage area 200.

In particular, when the pick-up device 10 is in the release position, the outer surface of at least one pull roller 32 is adapted to contact the outer surface of the tubular product 101 in order to pull at least one portion of the tubular product 101 towards the accumulation area 200.

The tensioning means 30 has at least one contrast roller 31, which is preferably arranged on the opposite side of each of the at least one pull-out rollers 32 with respect to the tubular product 101 during the rotational operation of the at least one pull-out roller 32.

According to a practical embodiment, the contrast roller 31 is supported by the pick-up device 10, while the pull-out roller 32 is supported by the turn-over device 20.

Naturally, nothing prevents the provision of various configurations of the tensioning means 30, both in terms of the arrangement of the various elements and the use of alternative tensioning elements, e.g. belts or similar elements.

Advantageously, the tensioning means 30 is functionally associated with a sensor means 36 adapted to control the conveyance of a portion of the tubular product 101 to the accumulation area 200.

By way of example, the sensor means 36 is arranged to detect the position of an axial end of the tubular product 101 opposite an axial end of the tubular product 101 associated with the support means 41.

The tensioning means 30 further comprises a lever 37 supported by the pick-up device 10, the lever 37 being configured to convey the tubular product 101 beneath the contrast roller 31 while the pick-up device 10 moves from the pick-up position to the release position.

The lever 37 is preferably actuated by an actuating means having, for example, a pneumatically actuated cylinder.

The lower portion 22 of the turning device 20 may be arranged to be commandably tilted with respect to the extension axis 103 when the tubular body 23 supported by the lower portion 22 is in the lowered position to facilitate the transfer of the tubular products 101 from the accumulation area 200 to the access inlet 21.

With reference to the embodiment shown in the drawings, the accumulation area 200 is located between the tensioning device 30 and the support means 41.

Of course, nothing prevents the accumulation area 200 from instead being located between the access inlet 21 and the needle cylinder 2.

During the suction process, the pulling means 30 is removed from the tubular product 101.

The present invention further provides a method for making a tubular product, comprising the steps of:
- manufacturing a tubular product 101 by means of at least one needle cylinder 2,
- picking up the tubular product 101 at its axial end by means of a pick-up device 10;
- transferring the axial end of the tubular product 101 from a pick-up position in at least one needle cylinder 2 to a release position in a station 40 for further processing of the tubular product 101;
- pulling at least one portion of the tubular product 101 by means of pulling means 30 acting in command on the outer surface of the tubular product 101 in order to transport at least one portion of the tubular product 101 to at least one accumulation area 200, and - sucking by means of suction means at least one portion of the tubular product 101 transported to the accumulation area 200 through an access entrance 21 towards a lower part 22 of an inverting device 20 configured to coaxially accommodate the tubular product 101 in order to invert the tubular product 101, in order to transfer the tubular product 101.

Indeed, it has been found that the present invention achieves its intended aims and objectives by providing a circular knitting machine and a method for manufacturing tubular products that can ensure efficient transfer of the tubular products to the turning device even in the case of very heavy or long tubular products.

The invention thus conceived is susceptible to numerous modifications and variations, all of which are within the scope of the appended claims, and all of the details may further be replaced by other technically equivalent elements.

In fact, the materials used and the associated shapes and dimensions can be anything depending on the requirements and current technology, so long as the materials used are suitable for the particular application.

The disclosures in Italian Patent Application No. 102021000014318, from which this application claims priority, are hereby incorporated by reference.

Although reference numbers are provided following technical features described in any claim, these reference numbers are included solely to enhance comprehension of the scope of the claim, and therefore, such reference numbers do not affect in any way the interpretation of the respective elements identified by such reference numbers as examples.

Claims (13)

A circular knitting machine (1) for hosiery or the like, comprising:
At least one needle cylinder (2) having a cylinder axis (100) and configured to produce a tubular product (101);
a pick-up device (10) adapted to reciprocate between a pick-up position arranged coaxially around the needle cylinder (2) for picking up the tubular product (101) from the needle cylinder (2) at an axial end of the tubular product, and a release position spaced laterally from the needle cylinder (2) for releasing the tubular product (101) at a further processing station (40) for further processing of the tubular product (101),
a turning-over device (20) is provided in the further processing station (40) having a lower part (22) extending about its extension axis (103) with an access inlet (21) formed in an upper region, the lower part (22) of the turning-over device (20) being adapted to coaxially receive the tubular product (101) for turning it over,
a pulling means (30) adapted to act in command on the outer surface of the tubular product (101) to convey at least one portion of the tubular product (101) to at least one accumulation area (200);
The turning-over device (20) is associated with suction means adapted to transfer at least one portion of the tubular product (101) conveyed to the accumulation area (200) towards the lower part (22) of the turning-over device (20) via the access inlet (21). The circular knitting machine (1) according to claim 1, wherein the accumulation area (200) is located immediately adjacent to the access opening (21). the turning-over device (20) has the lower part (22) and the upper part, the lower part (22) and the upper part being respectively arranged below and above an intermediate area in which a support means (41) for an everting tubular product (101) suspended at an axial end of the tubular product is arranged or can be arranged,
3. The circular knitting machine (1) according to claim 1 or 2, further comprising a tubular body (23) which can be inserted with its upper axial end from below upwards through the axial end of the tubular product (101) suspended from the support means (41) in order to turn over the tubular product held by the support means (41). The circular knitting machine (1) according to any one of claims 1 to 3, wherein the tensioning means (30) comprises at least one pull-out roller (32) associated with a motor means (35). The circular knitting machine (1) according to any one of claims 1 to 4, wherein the at least one pull-out roller (32) is arranged immediately adjacent to the accumulation area. The circular knitting machine (1) according to any one of claims 1 to 5, wherein when the pick-up device (10) is in the release position, the outer surface of the at least one pull-out roller (32) is adapted to contact the outer surface of the tubular product (101) in order to pull at least one portion of the tubular product (101) towards the accumulation area. The circular knitting machine (1) according to any one of claims 1 to 6, wherein the tensioning means (30) has at least one contrast roller (31), which is arranged on the opposite side of the pull-out roller (32) with respect to the tubular product (101) during the rotational movement of the at least one pull-out roller (32). The circular knitting machine (1) according to any one of claims 1 to 7, wherein the at least one contrast roller (31) is supported by the pick-up device (10) and the at least one pull-out roller (32) is supported by the inside-out device (20). The circular knitting machine (1) according to any one of claims 1 to 8, wherein the tensioning means (30) is functionally associated with a sensor means (36) adapted to control the conveyance of a portion of the tubular product (101) to the at least one accumulation area. The circular knitting machine (1) according to any one of claims 1 to 9, wherein the tensioning means (30) comprises a lever (37) supported by the pick-up device (10), the lever (37) being configured to convey the tubular product (101) below the contrast roller (31) during the transition from the pick-up position to the release position. The circular knitting machine (1) according to any one of claims 1 to 10, wherein the lower part (22) of the turning device (20) can be tilted on command with respect to the extension axis (103) when the tubular body (23) supported by the lower part (22) is in a lowered position. The circular knitting machine (1) according to any one of claims 1 to 11, wherein the accumulation area (200) is arranged between the tensioning means (30) and the support means (41). A method for making a tubular product (101), comprising the steps of:
- manufacturing a tubular product (101) by means of at least one needle cylinder (2),
- picking up said tubular product (101) by means of a pick-up device (10) at an axial end of said tubular product,
- transferring the axial end of said tubular product (101) from a pick-up position in said at least one needle cylinder (2) to a release position in a station (40) for further processing of said tubular product (101);
- pulling at least one portion of the tubular product (101) by means of pulling means (30) acting in command on the outer surface of the tubular product (101) in order to convey said at least one portion of the tubular product (101) to at least one accumulation area (200); and - sucking by means of suction means, through an access inlet (21), at least one portion of the tubular product (101) conveyed to said accumulation area (200) towards a lower part (22) of a turning device (20) configured to coaxially receive said tubular product (101) in order to turn said tubular product (101) over, in order to transfer said tubular product.

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