Patent Description:
In the field of the production of tubular knitted articles with circular knitting machines for hosiery or the like, in some cases there is the need to transfer the article from the machine used to produce the article to another production unit to perform additional work on the article that cannot be performed on said machine or that it is not economically convenient to perform on said machine. <CIT>, <CIT> and <CIT> describe pick up devices for transfer of knitted items.

In particular, in the field of the production of hosiery, in recent years methods have been developed for the automated execution of the closure of their toe by sewing or linking. Some of these methods are based on picking up the article from the machine used for its production and on its transfer to a station for additional work, which is distinct from the production machine, so as to close the toe of the hosiery item in the additional work station while the machine is used to produce another hosiery item. These methods have the advantage, with respect to other methods that are based on the execution of the closure of the toe of the hosiery item directly on the machine used for its production, of not penalizing excessively the productivity of the machine.

The transfer of the hosiery item, or more generally of the tubular article, from the machine used for its production to the station in which an axial end of the article is to be closed, or more generally additional work on the article is to be done, is performed generally by means of a pick-up device which, by means of pick-up elements, individually takes the loops of knitting the article from the needles of the machine and retains them during the transfer of the article.

In some methods for closing the toe of hosiery items, the pick-up device is used also to support the article during the execution of the additional work, while in other methods the pick-up device is used exclusively to transfer the article, since once it has reached the station in which the additional work is to be performed, it transfers the loops of knitting, previously picked up by the needles, to another device which has the function of supporting the article during the execution of the additional work, such as for example a handling device. This handling device arranges the loops that belong to one half of the row of knitting received from the pick-up device so that they face the loops that belong to the other half of the same row of knitting and supports the two half-rows of knitting in a mutually facing position during the intervention of a sewing or linking head, which joins the mutually facing pairs of loops of knitting.

In some pick-up devices of the known type used to simply transfer the article from the machine that produces it to a handling device, the coupling between the pick-up elements and the needles, in order to transfer the loops of knitting from the needles to the pick-up elements, usually occurs by means of the insertion of the head of the needle in a seat formed in the end of the pick-up element. For this reason, the pick-up device usually has an annular pick-up body, which is designed to face coaxially the end of the needle cylinder from which the heads of the needles protrude and which supports a plurality of pick-up elements oriented parallel to the axis of the pick-up body.

A pick-up device of this kind is shown for example in <CIT>.

Pick-up devices are also known, and described for example in <CIT>, which comprise an annular pick-up body which supports pick-up elements which can slide along radial directions with respect to the pick-up body. The pick-up body can be arranged coaxially around the needle cylinder of a circular hosiery knitting machine so that each one of the pick-up elements faces laterally a corresponding needle of the machine.

This type of pick-up device comprises actuation means which act on the pick-up elements in order to move them toward or away from the axis of the pick-up body so as to engage or disengage each pick-up element with respect to the needle which it is made to face and each one of the pick-up elements is adapted to pick up the loop of knitting of the article retained on the needle.

According to <CIT>, the end of each one of the pick-up elements that is directed toward the axis has a seat, which can engage a region of the stem of the needle that is located proximate to the latch of the needle on the opposite side with respect to the head, and the actuation means comprise elastic means which act on the pick-up elements in order to cause their sliding toward the axis and radial pushers which act on the pick-up elements to cause their sliding away from the axis in contrast with the action of the elastic means.

In the additional work station there is a handling device which is provided with an annular body arranged so that its axis is vertical. The annular body is provided, on its lower face, with a plurality of spikes arranged along an imaginary cylindrical surface the axis of which coincides with the axis and which extend parallel to said axis. The spikes are angularly mutually spaced around the axis uniformly along according to an angular spacing that corresponds to the spacing that exists between the pick-up elements of the pick-up device. In practice, each pick-up element is matched by a spike of the handling device and when the pick-up device is arranged in the additional work station the pick-up body of the pick-up device assumes a position that is coaxial to the body of the handling device with the pick-up elements arranged around the annular arrangement of spikes and with each pick-up element in radial alignment with a spike.

The aim of the present invention is to solve the problems described above, providing a system with a pick-up device for picking up a tubular knitted article from a circular knitting machine for hosiery or the like and for its transfer to a unit adapted to perform additional operations on the article that can be provided in a relatively simple manner and can be coupled to the needles of the machine with excellent precision.

Within this aim, an object of the invention is to provide a system that ensures high reliability in operation.

This aim, as well as this and other objects which will become better apparent hereinafter, are achieved by a system according to independent claim <NUM>.

Further characteristics and advantages of the invention will become better apparent from the description of a preferred but not exclusive embodiment of system according to the invention, illustrated by way of nonlimiting example in the accompanying drawings, wherein:.

The pick-up device is shown in its application to a single-cylinder knitting machine for hosiery or the like, generally designated by the reference numeral <NUM>, but it can also be used to pick up an article <NUM> from the needles arranged in the lower needle cylinder of a double-cylinder circular knitting machine for hosiery or the like or also to pick up an article from the needles located in the upper needle cylinder of a double-cylinder circular knitting machine for hosiery or the like. In this last case, however, the device according to the invention must be installed upside down with respect to what is shown in the accompanying figures.

With reference to the figures, the single-cylinder circular knitting machine for hosiery or the like <NUM>, designed to be served by the pick-up device, comprises a needle cylinder <NUM>, with a vertically oriented axis 121a. Multiple axial slots <NUM> are formed on the lateral surface of the needle cylinder <NUM> and a needle <NUM> is accommodated inside each one of them and can be actuated with an alternating motion along the corresponding axial slot <NUM> in order to form knitting.

In a per se known manner, inside the needle cylinder <NUM> there is a suction tube <NUM> which is coaxial to the needle cylinder <NUM>. This suction tube <NUM>, the upper end of which is open and goblet-shaped, can move along the axis 121a with respect to the needle cylinder <NUM> so that it can protrude, for a portion of its extension, from the upper end of the needle cylinder <NUM>.

The needles <NUM> are actuated in a per se known manner, for example by means of cams, not shown for the sake of simplicity, which are arranged around the needle cylinder <NUM> and can engage, as a consequence of the rotation of the needle cylinder <NUM> about its own axis 121a with respect to said cams, with the heels 123a of the needles <NUM> that protrude radially from the lateral surface of the needle cylinder <NUM>. The machine <NUM>, being a machine substantially of a known type, is not described further for the sake of simplicity.

With reference to the figures, the pick-up device designated generally by the reference numeral <NUM>, comprises a pick-up body <NUM>, which is annular and supports pick-up elements <NUM> which can slide, with respect to the pick-up body <NUM>, along radial directions. The pick-up body <NUM> can be arranged coaxially around the needle cylinder <NUM> of a circular hosiery knitting machine <NUM> so that each one of the pick-up elements <NUM> faces laterally a corresponding needle <NUM> of the machine <NUM>.

The pick-up device <NUM> comprises actuation means which act on the pick-up elements <NUM> in order to move them toward or away from the axis 11a of the pick-up body <NUM> so as to actuate the engagement or disengagement of each pick-up element <NUM> with respect to the needle <NUM> which it is made to face and each one of the pick-up elements <NUM> is adapted to pick up the loop of knitting of the article <NUM> retained on the needle <NUM>, as will become better apparent hereinafter.

The end 29a of each one of the pick-up elements <NUM> that is directed toward the axis 11a has a seat <NUM> which can engage a region of the stem 123b of the needle <NUM> that is located proximate to the latch 123d of the needle <NUM> on the opposite side with respect to the head 123c, and the actuation means comprise elastic means which act on the pick-up elements <NUM> to cause their sliding towards the axis 11a and radial pushers <NUM> which act on the pick-up elements <NUM> to produce their sliding away from the axis 11a in contrast with the action of the elastic means.

More particularly, the pick-up body <NUM> is arranged so that its axis 11a is vertical and is fixed to the end of an arm <NUM>, which is arranged horizontally and is connected, with its opposite end, to a sleeve <NUM> which has a vertical axis 13a. The sleeve <NUM> is fitted coaxially around a hollow shaft <NUM> and is integral therewith in rotation about its axis 13a. The hollow shaft <NUM> is supported, so that it can rotate about its own axis 13a, by a supporting structure <NUM> which can be constituted by the supporting structure of the machine <NUM> or by an autonomous supporting structure which optionally can be associated with the supporting structure of the machine <NUM>.

A gear <NUM> is keyed on the hollow shaft <NUM> and meshes with a gear <NUM> which is coaxial and integral with a helical gear <NUM> which mates with a worm gear <NUM> that is fixed to the output shaft of an electric motor <NUM> supported by the supporting structure <NUM>.

Essentially, the actuation of the electric motor <NUM> causes the rotation of the arm <NUM> about the axis 13a, which constitutes a vertical actuation axis for the arm <NUM> with respect to the supporting structure <NUM>, producing the transition of the pick-up body <NUM> from a pick-up position, in which it is arranged coaxially to the needle cylinder <NUM> of the machine <NUM>, to a release position, in which it is arranged at an additional work station <NUM>, constituted for example by a sewing or linking station, and vice versa, in which the unit adapted to perform additional work on the article <NUM> is arranged, as will become better apparent hereinafter.

Preferably, it is possible to stop the rotation of the arm <NUM> in a standby or intermediate position which is located between the pick-up position and the release position cited above.

The three positions, which can be assumed by the pick-up body <NUM> following the actuation of the electric motor <NUM>, are controlled by three sensors <NUM>, <NUM> and <NUM>, which detect references located on the block that supports the gear <NUM> and the helical gear <NUM>.

The station <NUM> for additional work of the article <NUM> comprises in particular a handling device <NUM> which has a plurality of spikes <NUM> arranged along a cylindrical surface and designed to engage the article <NUM>.

According to the invention, the pick-up body <NUM>, in the release position, is arranged coaxially to the cylindrical surface along which the spikes <NUM> are arranged.

The cylindrical surface along which the spikes <NUM> are arranged is spaced radially in the direction of the axis 11a of the pick-up body <NUM> with respect to the cylindrical surface along which the ends of the pick-up elements <NUM> directed toward the axis 11a, with the pick-up body <NUM> in the release position, are arranged.

The handling device <NUM> is provided with an annular body <NUM> which is arranged so that its axis 61a is vertical. The body <NUM> is provided, on its lower face, with the plurality of spikes <NUM>, which are arranged along an imaginary cylindrical surface the axis of which coincides with the axis 61a and which extend parallel to said axis 61a. The spikes <NUM> are mutually angularly spaced uniformly around the axis 61a.

The angular spacing may correspond to the one that exists between the pick-up elements <NUM> of the pick-up device <NUM>, but nothing forbids it from being also different, providing furthermore a different number of spikes <NUM> (preferably a smaller one) with respect to the number of the pick-up elements <NUM>.

When the pick-up device <NUM> is positioned in the additional work station <NUM>, the pick-up body <NUM> of the pick-up device <NUM> is located in a position that is coaxial to the body <NUM> of the handling device <NUM> with the pick-up elements <NUM> arranged around and externally with respect to the ring of spikes <NUM>.

The sleeve <NUM>, with the arm <NUM> connected thereto, can move on command along the axis 13a with respect to the hollow shaft <NUM>. More particularly, the sleeve <NUM> is integral with a female thread <NUM> which has a vertical axis and with which a threaded shaft <NUM> mates and is connected, by means of a coupling <NUM>, to the output shaft of an electric motor <NUM> which is supported by a block that is fixed to the hollow shaft <NUM>.

In this manner, an actuation of the electric motor <NUM> causes the lifting or lowering of the arm <NUM> in any angular position of the arm <NUM> about the axis 13a.

The pick-up body <NUM> of the pick-up device <NUM> has a plurality of radial slots <NUM> inside each of which a pick-up element <NUM> is accommodated slidingly.

Each pick-up element <NUM>, as shown in particular in <FIG>, is provided with a laminar body which is arranged on a plane which is radial with respect to the axis 11a of the pick-up body <NUM>. The end of each pick-up element <NUM> that is directed toward the axis 11a is provided with a seat <NUM>, which is open both toward the axis 11a and parallel to said axis 11a, i.e., both above and below. This seat <NUM>, when the pick-up body <NUM> is in the pick-up position, can be coupled to the stem 123b of a needle <NUM> which the pick-up element <NUM> faces.

More particularly, the pick-up body <NUM> of the pick-up device <NUM> supports a number of pick-up elements <NUM> that matches the number of the needles <NUM> of the machine <NUM> and said pick-up elements <NUM> are angularly spaced around the axis 11a of the pick-up body <NUM> in a manner that corresponds to the angular spacing, around the axis 121a of the needle cylinder <NUM>, that exists between the needles <NUM> of the machine <NUM>. Furthermore, the pick-up body <NUM>, in a peripheral region, supports a centering pin <NUM>, which has a vertical axis and which, by means of the lowering of the arm <NUM>, which can be actuated by means of the electric motor <NUM>, can be inserted in a corresponding centering seat provided in the supporting structure of the machine <NUM> laterally to the needle cylinder <NUM> and not shown for the sake of simplicity. The coupling between the centering pin <NUM> and the corresponding centering seat ensures the precise positioning of the pick-up body <NUM> and of the pick-up elements <NUM> with respect to the needle cylinder <NUM> of the machine <NUM>. Adapted control elements, usually provided in modern circular knitting machines for hosiery or the like, allow precise angular positioning of the needle cylinder <NUM> about its own axis 121a with respect to the supporting structure of the machine and therefore allowed to position each needle <NUM> of the machine in radial alignment with the seat <NUM> of a corresponding pick-up element <NUM> when required.

The centering pin <NUM> can be disengaged from the corresponding centering seat by lifting the arm <NUM> in order to allow the rotation of the arm <NUM> about the axis 13a.

Each pick-up element <NUM> rests, with one of its sides, on the bottom of a corresponding radial slot <NUM> and protrudes from it, in the direction of the axis 11a, with its end in which the seat <NUM> is formed. It should be noted that the seat <NUM> can be delimited laterally by two mutually opposite walls, as in the illustrated embodiment, but it can also be delimited only on one side by a single wall.

Preferably, the end 29a of each pick-up element <NUM> is shaped like a hook which is open upward and the seat <NUM> is formed on the back of the hook.

The end 29b, arranged opposite the end 29a, of each pick-up element <NUM> is shaped like a heel which extends parallel to the axis 11a and protrudes above the corresponding radial slot <NUM> of the pick-up body <NUM>, so as to form a shoulder <NUM> that is directed toward the axis 11a. The elastic means which push the elements <NUM> toward the axis 11a act against the side of this heel that is directed opposite with respect to the axis 11a. Said elastic means are preferably constituted by an annular helical spring <NUM> the axis of which coincides with the axis 11a and which is arranged around the pick-up elements <NUM> and acts on the side of the end 29b, which is heel-shaped, that is opposite with respect to the shoulder <NUM>.

The radial pushers <NUM> are arranged in the pick-up body <NUM> and act on command on the shoulder <NUM> so as to cause the sliding of the pick-up elements <NUM> away from the axis 11a in contrast with the action of the helical spring <NUM>.

More particularly, the pick-up body <NUM> is closed in an upper region by a fixed plate <NUM> which is annular and is arranged concentrically to the axis 11a. Five radial pushers <NUM> are arranged inside the pick-up body <NUM>, are shaped like annular sectors and face the shoulder <NUM> of the pick-up elements <NUM>. Each one of these radial pushers <NUM> is fixed to a pair of pins <NUM>, which are mutually angularly spaced around the axis 11a and are oriented parallel to the axis 11a. These pins <NUM> pass slidingly through first slits <NUM> which are formed in the fixed plate <NUM>. The pairs of first slits <NUM> with which the pins <NUM> of a same radial pusher <NUM> engage are mutually parallel and are oriented so as to allow the corresponding radial pusher <NUM> to move radially toward and away from the axis 11a. A movable plate <NUM> is arranged above the fixed plate <NUM>, is also annular, is arranged concentrically to the axis 11a and is supported, so that it can rotate about the same axis 11a, by the pick-up body <NUM>. The movable plate <NUM> is crossed by second slits <NUM>, one for each pin <NUM>, which are each crossed slidingly by a pin <NUM>. The second slits <NUM> are inclined with respect to the first slits <NUM> so that a rotation of the movable plate <NUM> about the axis 11a with respect to the pick-up body <NUM> and the fixed plate <NUM> causes a movement of the radial pushers <NUM> toward or away from the axis 11a.

The movable plate <NUM> is connected to a linear actuator which is provided with stroke adjustment means.

Preferably, the linear actuator comprises the stem of the piston of a double-acting fluid-operated cylinder <NUM> which is mounted on the arm <NUM> and can be actuated to cause the rotation of the movable plate <NUM> about the axis 11a with respect to the pick-up body <NUM>.

In practice, the actuation of the fluid-operated cylinder <NUM> causes the rotation of the movable plate <NUM> about the axis 11a with respect to the pick-up body <NUM> in one direction, producing the spacing of the radial pushers <NUM> and therefore of the pick-up elements <NUM> from the axis 11a in contrast with the action of the helical spring <NUM>, as shown in particular in <FIG>, <FIG>, or in the opposite direction, producing the approach of the radial pushers <NUM> to the axis 11a, allowing the movement of the pick-up elements <NUM> toward said axis 11a by virtue of the action of the helical spring <NUM>, as shown in particular in <FIG>, <FIG>. The stroke of the pick-up elements <NUM> toward the axis 11a is delimited by a shoulder <NUM> which is arranged opposite the shoulder <NUM> and is formed inside the pick-up body <NUM> or by the radial pushers <NUM>.

It should be noted that each pick-up element <NUM> engages the stem 123b of the corresponding needle <NUM> by virtue of the action of the spring <NUM>. As a consequence of this fact, a sort of adaptation of the stroke of each pick-up element <NUM> in the direction of the axis 11a to the actual radial position of the corresponding needle <NUM> is achieved. In practice, the particular actuation of the pick-up elements <NUM> makes the coupling of each pick-up element <NUM> to the corresponding needle <NUM> less critical, since it can obviate imprecise radial placements of the needles <NUM>, thus ensuring in any case a precise mating. Furthermore, the particular actuation of the pick-up elements <NUM>, in addition to allowing excellent containment of the axial space occupation of the pick-up body <NUM> as a whole, also allows to use a same pick-up device <NUM> with machines that have the same number of needles but are arranged along cylindrical surfaces that have slightly different diameters.

The pick-up device <NUM> also comprises a presser <NUM>, which has a circular plan shape with a perimetric profile that is shaped like a comb with a plurality of teeth arranged around the axis 42a, which is oriented vertically, of the presser <NUM>.

The presser <NUM> is connected to one end of a corresponding arm <NUM> which, in the illustrated embodiment, is arranged above the arm <NUM>. The arm <NUM> is connected, with its opposite end, to a corresponding sleeve <NUM> which is arranged coaxially to the sleeve <NUM> and mates, so as to be able to rotate about the axis 13a and so as to be able to slide along said axis 13a, in a cylindrical seat <NUM> formed in the sleeve <NUM>.

The arm <NUM> rests against the upper end of posts <NUM> which have a vertical axis, are arranged around the axis 13a and are accommodated, so that they can slide axially, in corresponding seats <NUM> formed by the sleeve <NUM>. The arm <NUM> rests on the posts <NUM> by means of a bearing <NUM>, the axis of which coincides with the axis 13a so as to reduce the sliding of the arm <NUM> on the posts <NUM> during a rotation of the arm <NUM> with respect to the arm <NUM> about the axis 13a.

The posts <NUM> are pushed in the direction of the arm <NUM>, and therefore upward in the illustrated embodiment, by springs <NUM> which are interposed between the posts <NUM> and the corresponding seats <NUM>.

The sleeve <NUM> supports a fluid-operated cylinder <NUM>, which has a vertical axis and rests with the stem of its piston against the sleeve <NUM>. In practice, the fluid-operated cylinder <NUM> is integral with the sleeve <NUM> in rotation about the axis 13a and in translation along said axis 13a and can be actuated in order to produce the translation, downward in the illustrated embodiment, of the sleeve <NUM> and therefore of the arm <NUM> along the axis 13a with respect to the arm <NUM> in contrast with the action of the springs <NUM>.

The arm <NUM>, on its side directed toward the arm <NUM>, is provided with a pin <NUM> which has a vertical axis and which, by means of the translation of the arm <NUM> with respect to the arm <NUM> along the axis 13a, can be inserted in a seat <NUM> having a vertical axis which is formed in the arm <NUM> or can be extracted from said seat <NUM>.

The coupling of the pin <NUM> to the seat <NUM> ensures the coaxial arrangement of the presser <NUM> with respect to the pick-up body <NUM> and at the same time renders mutually integral the arm <NUM> and the arm <NUM> and therefore the presser <NUM> and the pick-up body <NUM> in rotation about the axis 13a.

The inlet of the seat <NUM> is formed on the bottom and at a closed end of a slot <NUM> which is formed on the face of the arm <NUM> that is directed toward the arm <NUM>. This slot <NUM> is shaped like a circular sector that is centered on the axis 13a and is open at one of its ends that is opposite with respect to the end occupied by the seat <NUM>. In the condition of maximum spacing of the arm <NUM> above the arm <NUM>, the lower end of the pin <NUM> is at such a level as to disengage from the seat <NUM> but be able to engage with the slot <NUM>, as shown for example in <FIG> and <FIG>. In this manner, in the condition of maximum spacing of the arm <NUM> above the arm <NUM>, the arm <NUM> can rotate about the axis 13a with respect to the supporting structure <NUM>, disengaging from the arm <NUM> in one direction since the pin <NUM> exits from the open end of the slot <NUM> while in rotation in the opposite direction it engages the arm <NUM>, since the pin <NUM> enters said open end of the slot <NUM>, engaging therewith, as will become better apparent hereinafter.

The presser <NUM>, particularly when it is in a position that is coaxial to the pick-up body <NUM>, can move, by means of the actuation of the fluid-operated cylinder <NUM>, from a raised position, in which it is spaced upward from the pick-up body <NUM>, as shown for example in <FIG>, <FIG>, <FIG>, <FIG> and <FIG>, to a lowered position, in which it penetrates with the teeth of its perimetric profile between the pick-up elements <NUM>, as shown for example in <FIG>, <FIG> and <FIG>.

Along the trajectory followed by the arm <NUM> in its rotation about the axis 13a there is an abutment <NUM> which stops the rotation of the arm <NUM>, in the raised position, in a position that substantially corresponds to the intermediate position of the arm <NUM> between the machine <NUM> and the additional work station <NUM>, preventing the arm <NUM> from following the arm <NUM> in the additional work station <NUM>. Vice versa, when the arm <NUM> rotates about the axis 13a from the additional work station <NUM> to the machine <NUM> and reaches the intermediate position in which it has previously abandoned the arm <NUM>, the pin <NUM> enters the slot <NUM> and, at the end thereof, i.e., when the pin <NUM> is coaxial to the seat <NUM>, entrains in its rotation toward the machine <NUM> the arm <NUM>.

The seat <NUM> that is present in the end of each pick-up element <NUM> that is directed toward the axis 11a and can be coupled to a needle of the machine <NUM> can be mated likewise to a spike <NUM> by means of an axial movement of the pick-up body <NUM> and by means of a radial movement of the pick-up elements <NUM> with respect to the spikes <NUM>.

The body <NUM> can be composed, in a per se known manner, by two annular portions 63a, 63b which are mutually pivoted about a diametrical axis <NUM>. One of the two annular portions, constituted by the annular portion 63b, can be turned over on command with respect to the other annular portion 63a about the diametrical axis <NUM> so as to move each spike <NUM> of the annular portion 63b so that it faces a corresponding spike <NUM> of the annular portion 63a. In the illustrated embodiment, when the two annular portions 63a, 63b are in a coplanar position, the spikes <NUM> are directed with their tip downward and the annular portion 63b can be turned over about the diametrical axis <NUM> so as to face the annular portion 63a in a downward region.

Furthermore, at the station <NUM> there is an annular body <NUM> which can be accommodated coaxially in an annular seat <NUM> the axis of which coincides with the axis 61a. The annular body <NUM> is connected to the stem of the piston of a fluid-operated center, not shown, which is oriented so that its axis is parallel to the axis 61a. This fluid-operated cylinder can be actuated in order to produce the movement in one direction or in the opposite direction of the annular body <NUM> along the axis 61a.

The perimetric profile of the face of the annular body <NUM> that is directed upward is preferably comb-shaped, with teeth which can be inserted between the pick-up elements <NUM> of the pick-up device <NUM> when the pick-up body <NUM> is moved into the additional work station <NUM>.

The operation of the pick-up device according to the invention is as follows.

The article <NUM> is produced on the circular knitting machine for hosiery or the like by beginning its production from one axial end and ending it at the opposite axial end.

While the machine <NUM> is ending the production of the article <NUM>, the pick-up device <NUM> is located with its pick-up body <NUM> in the intermediate position between the machine <NUM> and the additional work station <NUM> with the pick-up elements <NUM> in a position that is spaced from the axis 11a of the pick-up body <NUM>. The presser <NUM> is arranged above and coaxially to the pick-up body <NUM> and is raised with respect to it.

Each loop of knitting of the last row of knitting formed is retained on the needle <NUM> that produced it. The dial, not shown for the sake of simplicity, which is arranged above and coaxially to the needle cylinder <NUM>, after the cutter, which is integral with the dial, has cut the yarn used to produce the article <NUM>, is spaced upward from the needle cylinder <NUM> in order to allow the arrangement, above and coaxially to the needle cylinder <NUM>, of the pick-up body <NUM> of the pick-up device <NUM> with the corresponding presser <NUM> arranged above and coaxially to the pick-up body <NUM>, as shown in <FIG>.

It should be noted that the pick-up device <NUM> is arranged so that the pick-up body <NUM> is above the needle cylinder <NUM> and is then lowered along the axis 11a, which coincides with the axis 121a, by means of the actuation of the electric motor <NUM> so that the centering pin <NUM> enters the adapted seat provided in the supporting structure of the machine <NUM>.

The needle cylinder <NUM> continues to be actuated with a rotary motion about its own axis 121a so that the needles <NUM>, by means of the needle actuation cams, are first raised into the tuck-stitch position and then returned with their head 123c below the sinkers <NUM> to be then raised again to the tuck-stitch position, lifting simultaneously the suction tube <NUM> so that the loops of knitting of the last row of knitting of the article <NUM> that have been formed are assuredly in the head 123c of the corresponding needle <NUM> with the latches 123d of the needles <NUM> open. Finally, the needles <NUM>, again by means of the rotation of the needle cylinder <NUM> with respect to the needle actuation cams, are all raised to the tuck-stitch position together with the suction tube <NUM>. At this point, the rotation of the needle cylinder <NUM> is stopped and the needle cylinder <NUM> is locked mechanically so as to exclude a random or accidental rotation thereof during subsequent steps. In this rotational position of the needle cylinder <NUM>, the end 29a of each pick-up element <NUM> that is directed toward the axis 11a is radially aligned with the stem 123b of a corresponding needle <NUM>.

At this point the fluid-operated cylinder <NUM> is actuated and, by rotating the movable plate <NUM>, causes the movement of the radial pushers <NUM> toward the axis 11a, thus allowing the pick-up elements <NUM> to move toward the axis 11a by virtue of the action of the thrust applied by the spring <NUM>, as shown in <FIG>, <FIG>. The end of each pick-up element <NUM> that is directed toward the axis 11a rests with the seat <NUM> against the stem 123b of the corresponding needle <NUM> directly below the latch 123d of the same needle <NUM>, as shown in <FIG> and more particularly in <FIG>, which show exclusively the coupling of a pick-up element <NUM> to a needle <NUM>.

After the engagement of the pick-up elements <NUM> against the stem 123b of the corresponding needle <NUM>, the pick-up body <NUM> is raised slightly, by means of the actuation of the electric motor <NUM>, so that the end 29a of each pick-up element <NUM> engages, by means of the seat <NUM>, the stem 123b of the needle <NUM> between the free end of the open latch 123d of a needle <NUM> and the stem 123b of said needle <NUM>.

Then the suction tube <NUM> is lowered and, by means of the actuation of the fluid-operated cylinder <NUM>, the transition of the presser <NUM> to the lowered position is produced, in which it enters with the teeth of its perimetric profile between the needles <NUM> and between the pick-up elements <NUM>. As a consequence of this axial movement of the presser <NUM>, the loops of knitting are pushed into the hook-shaped end 29a of the pick-up elements <NUM> below the latches 123d of the needles <NUM>, as shown in <FIG> and <FIG>. Furthermore, the pin <NUM> engages in the seat <NUM>, rendering mutually integral, in rotation about the axis 13a, the arm <NUM> and the arm <NUM>.

The pick-up body <NUM> of the pick-up device <NUM> is then raised along its own axis 11a with respect to the needle cylinder <NUM> together with the presser <NUM> by means of the actuation of the electric motor <NUM>. This lifting, by virtue of the sliding toward the head 123c of the corresponding needle <NUM> of the pick-up elements <NUM> that previously were arranged with their end 29a below the open latch 123d of the corresponding needle <NUM>, causes the closure of the latches 123d onto the heads 123c of the needles <NUM> and the disengagement of the loops of knitting from the needles <NUM>, as shown in <FIG>.

In this step, the suction tube <NUM> is raised again in order to assist the rise of the article <NUM> and protect the article <NUM> from contact with the parts of the machine that are located about the needles <NUM> in the subsequent step.

By means of the actuation of the electric motor <NUM>, the arms <NUM> and <NUM> are then rotated about the axis 13a so as to transfer the pick-up body <NUM> of the pick-up device <NUM> and the presser <NUM> from the machine <NUM> to the intermediate position between the machine <NUM> and the additional work station <NUM>, as shown in <FIG>. In this intermediate position the fluid-operated cylinder <NUM> is deactivated so that the arm <NUM>, which supports the presser <NUM>, disengages with its pin <NUM> from the seat <NUM>.

The rotation of the arm <NUM> about the axis 13a is then completed by means of the electric motor <NUM> until the pick-up body <NUM> is arranged so that its axis 11a is at the axis 61a in the further processing station <NUM>, as shown in <FIG>. It should be noted that in the completion of the rotation of the arm <NUM> about the axis 13a the arm <NUM> does not follow the arm <NUM>, since its rotation is blocked by the abutment <NUM> and the slot <NUM> slides along the pin <NUM>, disengaging from it. Optionally, in this position the article <NUM> can be aspirated pneumatically into a tubular body which is arranged below and coaxially to the pick-up body <NUM>.

The pick-up body <NUM>, which is located below the two annular portions 63a, 63b, which are mutually coplanar, is then raised by means of the actuation of the electric motor <NUM>.

The annular body <NUM> is then raised along the axis 61a and penetrates with the teeth of its perimetric profile between the pick-up elements <NUM>, causing the penetration of the spikes <NUM> in the knitting.

At this point the article <NUM> can be turned inside out above the body <NUM>, making it pass axially through it, in a per se known manner, for example by pneumatic suction or by means of a turner tube which can be inserted axially through the body <NUM>.

The annular body <NUM> is then returned to the lowered position and the pick-up body <NUM> of the pick-up device <NUM> is spaced from the additional work station <NUM> and returned to the intermediate position by means of a lowering produced by the activation of the electric motor <NUM> and by means of a rotation about the axis 13a produced by the actuation of the electric motor <NUM>, as shown in <FIG>.

In the additional work station <NUM>, work on the article <NUM> can continue in a per se known manner for example by means of a non-linked sewing of the two annular portions by means of the overturning of the annular portion 63b below the annular portion 63a and by means of the subsequent sewing, thus closing an axial end of the article <NUM>.

In practice it has been found that the system according to the invention fully achieves the intended aim and objects.

A further advantage of the system according to the invention is that it can have a reduced axial space occupation for the pick-up body and therefore can require a minimal lifting of the dial, if it is used on a single-cylinder knitting machine, or of the upper needle cylinder if it is used on a double-acting circular machine.

A further advantage of the system according to the invention is that it can be used to pick up articles from needles or to transfer articles onto spikes which are arranged according to different cylindrical surfaces having different diameters.

The system thus conceived is susceptible of numerous modifications and variations, all of which are within the protective scope of the appended claims.

Claim 1:
A system comprising a circular knitting machine for hosiery (<NUM>), a pick-up device (<NUM>) and a station (<NUM>) wherein the pick-up device (<NUM>) is configured to pick up a tubular knitted article from the machine (<NUM>) and for its transfer to a unit adapted to perform additional operations on the article, the pick-up device (<NUM>) comprising an annular pick-up body (<NUM>) which supports pick-up elements (<NUM>) which can slide relative to said pick-up body (<NUM>) along radial directions, said pick-up body (<NUM>) being configured to be arrangeable coaxially around the needle cylinder (<NUM>) of the machine (<NUM>) so that each one of said pick-up elements (<NUM>) faces laterally a needle (<NUM>) of the machine (<NUM>); actuation means being provided which act on said pick-up elements (<NUM>) for their movement toward or away from the axis (11a) of said pick-up body (<NUM>), for the engagement or disengagement of each pick-up element (<NUM>) with the needle (<NUM>) of the machine (<NUM>) which it is made to face, and each one of said pick-up elements (<NUM>) being adapted to pick up the loop of knitting held on said needle (<NUM>), said pick-up body (<NUM>) is movable on command from a pick-up position, in which it is configured to be arranged coaxially around the needle cylinder (<NUM>) of the machine (<NUM>) , to a release position, in which it is configured to be arranged at the station (<NUM>) for further processing which is spaced laterally with respect to the needle cylinder (<NUM>) of the machine (<NUM>) and in which said unit adapted to perform additional operations on the article (<NUM>) is arranged, with said pick-up body (<NUM>) in said release position, said station (<NUM>) for further processing of said article (<NUM>) comprising a handling device (<NUM>) provided with a plurality of spikes (<NUM>) which are arranged along a cylindrical surface and are designed to engage said article (<NUM>), said pick-up body (<NUM>), in said release position, being arranged coaxially to said cylindrical surface, characterized in that, in said release position, said cylindrical surface of spikes is spaced radially in the direction of said axis (11a) of said pick-up body (<NUM>) with respect to the cylindrical surface along which the ends of said pick-up elements (<NUM>) directed toward the axis (11a) are arranged with said pick-up body (<NUM>).