"DEVICE AND METHOD TO ALIGN THE EDGE SURROUNDING AN END OF A TUBULAR KNITTED ARTICLE"

DESCRIPTION Technical Field The present invention relates to a machine or device for handling tubular knitted articles, such as in particular - but not exclusively - stockings and socks.

More specifically, the present invention relates to a device useful for preparing tubular knitted articles of the aforesaid type - which are unloaded from the knitting machine in which they are produced with the toe open - for the subsequent operations to sew the toe. State of the Art

WO-A-2005/100664 describes a complex machine, comprising a plurality of stations having the function of picking up the individual socks or other tubular knitted articles from a basket and preparing them for sewing in a sewing machine comprising a guillotine. One of these stations has the function of aligning approximately on a plane the edge or band surrounding one of the ends of the article and more specifically the edge surrounding the open toe thereof. This station comprises an operating head provided with a plurality of contact mem- bers, controlled in order to selectively move toward an article inserted on a tubular support and transport member. The relative movement between the tubular member, with the tubular article inserted thereon, and the contact members is such that contact between these members and the tubular article takes place in different times according to the position of the tubular knitted article on the tubular transport member. The tubular knitted article is made to slide on the tubular transport member by the pads which gradually come into contact therewith and press it on the surface or side wall of the tubular transport member. The final result of the operation is to align approximately on a plane orthogonal to the axis of the tubular transport member all the portions of the edge surrounding the open toe of the tubular knitted article, so that the entire band or edge surrounding the toe opening is approximately on the same plane substantially orthogonal to the axis of the tubular member. This facilitates the subsequent operations to pick up and insert the toe of the tubular knitted article in the sewing machine.

Object and summary of the Invention

According to a particular aspect, an object of the invention is to improve the device described above to make it faster and more reliable.

In substance, this and other objects and advantages, which will be clear to those skilled in the art from reading the text below, are obtained with a device of the type mentioned above, wherein the operating head comprises, besides the pads, at least one wheel or preferably a pair of wheels to act on the fabric of the tubular knitted article. These wheels, suitably motorized, perform the movement of the part of the fabric of the tubular knitted article, which at the beginning of the operating cycle is above the front end of the tubular transport member. In this way the step to unload the tubular knitted article from the front portion of the tubular transport member is accelerated, as is the subsequent alignment step through the movement of the pads, which come gradually, and selectively into contact with the textile material of the tubular knitted article in- serted on the tubular member.

Further features and preferred embodiments of the invention will be described in greater detail below with reference to the drawings and are indicated in the appended claims, which form an integral part of the present description. Brief description of the drawings The invention will be better understood by following the description and accompanying drawing, which shows a practical non-limiting embodiment of the invention. More specifically, in the drawing:

Figure 1 shows an overall side view of the device with the operating head and the tubular member with the tubular knitted article inserted thereon; Figure 1A shows a section according to 1A-1A in Figure 1;

Figure 2 shows a view analogous to Figure 1 in the first operating step; Figures 3A, 3B and 3C shows subsequent operating steps of a possible work cycle;

Figures 4 and 5 show a further two operating steps of a possible operat- ing cycle.

Detailed description of an embodiment of the invention

The device comprises an operating head 1432 which cooperates with a tubular member 377, on which the tubular knitted article is disposed, for example to transport it through subsequent stations of a same machine. In the em-

bodiment shown the arrangement of the tubular transport member 337 is vertical, but it must be understood that the orientation of the entire machinery can be rotated, i.e. placing the tubular transport member 337 with the axis thereof horizontal or even with an intermediate inclination. According to a possible embodiment, the station 1432 comprises a plate

1435 facing a front end of the tubular member 337. The plate 1435 and the tubular member 337 are movable with respect to each other according to the double arrow f1435 to move reciprocally toward or away from each other. Advantageously, the operating head 1432 is movable in a direction substantially parallel to the axis of the tubular member 337, while the tubular member is fixed or is provided with a movement orthogonal to the axis thereof to transfer the tubular knitted article from one station to the other of the machine. According to a possible embodiment an actuator 1437 is provided to impart the movement to said plate 1435. In the embodiment shown a piston-cylinder 1437 is provided, but other embodiments are possible, including one with a electric stepper motor and a threaded bar engaging in a female screw, or other type of actuators.

According to an advantageous embodiment, a bracket 1439 connected rigidly to the plate 1435 supports an oscillating lever 1441 , hinged in 1443 to the bracket 1439. An actuator 1445 controls the oscillating movement of the lever 1441. At an end thereof, the lever 1441 supports a first wheel 1447, the rotation of which is controlled by an electric motor (not shown) or by another suitable source of motion.

The oscillating lever 1441 supports an oscillating bracket 1449 hinged to the lever 1441 coaxially to the wheel 1447. An actuator 1451 controls the oscillating movement of the oscillating bracket 1449 around the axis of oscillation thereof. The oscillating bracket 1449 supports a second wheel 1453, which is connected to the wheel 1447 through a motion transmission belt 1455, so that this motor (not shown) will make both the wheels 1447, 1453 rotate. It would also be possible to provide a second separate motor for the wheel 1453, although the arrangement shown is preferred as it requires a more limited number of mechanical parts.

According to a possible embodiment the plate 1435 supports an additional actuator 1461 connected to a supporting member 1463 disposed below

the plate 1435. A plurality of brackets 1465 are rigidly connected and extend below the supporting member 1463. In a possible embodiment three of these brackets 1465 are provided, spaced from one another by 90° (see Figure 1A) about the axis Ax-Ax of the device. In an advantageous embodiment, each bracket 1465 is provided with a movable pad 1467. Each pad 1467 is movable in a radial direction, i.e. substantially orthogonal to the axis Ax-Ax, and the movement thereof is controlled by actuators 1469.

In an advantageous embodiment, tabs 225 are provided housed inside the tubular member 337, extractable and retractable through slots provided in the cylindrical side wall of this tubular member. The tabs and the slots extend in a direction substantially parallel to the axis of the tubular member. In a preferred embodiment the tabs 225 are provided with slots or longitudinal slotted openings indicated with 225X.

The wheels 1447, 1453 and each pad 1467 are provided with respective sensors which, in a preferred embodiment, comprise an optical emitter and an optical receiver, indicated with 1471 and 1473 and arranged one in front of the other so that a beam of light passes through the slots 225X at least during a part of the operating cycle, as will be described better in greater detail below.

The device 1432 operates as follows: in Figure 1 the tubular member 377 and the tubular knitted article M are taken into alignment with the plate 1435 of the device 1432. The toe of the article M partially covers the upper edge of the tubular member 377 and the plate 1435 is arranged at a distance with respect to the tubular member 377, so that the pads 1467 and the wheels 1447 and

1453 are not touching the tubular member 377 and the article M disposed thereon.

In the subsequent step (Figure 2), the actuator 1437 lowers the plate 1435 and the oscillating lever 1441 is made to oscillate counter-clockwise until the wheel 1447 is pressing against the upper edge of the tubular member 377. The oscillating bracket 1449 is also moved to press the wheel 1453 against the side surface of the tubular member 377. In a preferred embodiment in this step the tabs 225 are retracted inside the tubular member 377, i.e. they are not projecting from the cylindrical side surface of the tubular member 377.

The wheels 1447, 1453 are made to rotate until the fabric of the toe of the article M has been fully removed from the edge of the tubular member 377 and

made to slide along the cylindrical side surface thereof for a certain length (see Figure 3A). In a possible operating mode, at this point the tabs 225 are partially extracted and the direction of rotation of the wheels is reversed, so that the portion of fabric engaged by the wheel 1453 is moved slightly toward the upper edge of the tubular member 377. This movement is halted as soon as the sensor 1471 detects the edge or band F of the toe P of the tubular knitted article M through the slotted hole 225X produced inside the corresponding tab 225. The final position is shown in Figure 3B. In the absence of slotted holes 225X the optical sensors can be arranged so that they detect the thickness of the fabric on the longitudinal edge of the tabs 225.

The remaining part of the band or edge F is normally in a lower position not known in advance. The object of the subsequent steps of the operating cycle is to align the entire band F of the toe at approximately the same height, i.e. approximately on a plane substantially orthogonal to the axis of the tubular member 377.

To attain this object, according to a preferred embodiment of the invention, the supporting member 1463 is gradually moved toward the tubular member 377. Each pad 1467 is thus lowered (Figure 3C). As soon as the corresponding sensor 1473 detects the edge or band F surrounding the toe of the tubular knitted article M, the corresponding actuator 1469 pushes the pad against the tubular member 377 or preferably against the radially projecting longitudinal edge of the respective partially extracted tab 225. Detection is facilitated by the slots 225X ₁ as the beam of light of the sensors passes through said slots 225X and is interrupted as soon as the beam encounters the fabric. The same operating mode is provided for the sensor 1471.

Subsequently, the movement of the supporting member 1463 is preferably continued for a certain length after each pad 1467 has been moved against the tubular member 377 or the tab 225. Once the pad 1467 has been moved to press against the edge of the corresponding tab 225, it draws the fabric along the edge of this tab until the supporting member 1463 is halted. Consequently, as all the sensors 1473 are disposed in the same position with respect to the corresponding pad 1467, at the end of the downward travel of the supporting member 1463 the portions of fabric in contact with the pads 1467 are all at the same height with respect to the upper edge of the tubular member 377, as

shown in Figure 4.

According to a preferred embodiment of the invention, the movement of the supporting member 1463 is then reversed until the pads 1467 have taken the fabric to the same height with respect to the portion of fabric engaged by the wheel 1453. The final result of this operation is shown in Figure 5: the band or edge F of the toe P of the tubular knitted article M is approximately aligned along a plane parallel to the upper edge of the tubular member 377.

It must be understood that slightly different operating sequences from those described can be utilized to obtain the final result of alignment of the edge F of the tubular knitted article M. However, in general the device will perform a first step to unload the pocket of fabric of the toe from the portion or front end of the tubular member 377 through the wheels 1447, 1453, this operation being performed by a reciprocal movement between operating head 1432 and tubular member* 1437 along the direction parallel to the axis of this tubular member, in combination with the substantially radial movement of the pads 1467 controlled selectively by means of signals generated by the sensors 1473. Closing and sliding of the pads on the tubular member 377 ultimately takes the edge F of the toe P to an alignment at the desired height.

It is understood that the drawing only shows an embodiment of the inven- tion, which can vary in forms and arrangements without however departing from the scope of the concept underlying the invention. Any reference numerals in the appended claims are provided to facilitate reading of the claims with reference to the description and to the drawing, and do not limit the scope of protection represented by the claims.