APPARATUS FOR FINISHING MEN'S SOCKS Technical field

[01] The present invention relates to an apparatus for finishing men's socks and the like.

Background of the invention

[02] It is known that, during the manufacturing process, men's socks are subjected to a series of finishing treatments intended to give the socks suitable characteristics. In particular, men's socks are subjected to a thermal boarding treatment by pressurized steam.

[03] To carry out this treatment, the socks are put and stretched on special forms of metal material, preferably made of aluminum, by means of which the socks are then led, stepwise, into the operating stations of the finishing apparatus. Boarding shapes consist in particular of shapes conforming the profile of the foot. Boarding shapes have different dimensions depending on the size of the socks to be made, from the child to the adult, with consequent less or greater use of metal material. The smaller sized boarding shapes have a narrow leg and short foot; the larger sized boarding shapes have a wide leg and a long foot.

[04] The boarding shapes are mounted in a vertical position on transport devices designed to move the shapes, generally with reciprocating motion, on a closed path, along whose sides the operating stations of the apparatus are arranged. The transport devices may each carry a pair of boarding shapes, for example.

[05] Patent application WO 2006/0131353 illustrates a method for treating socks, according to which the socks put and stretched on respective shapes are moved on a closed path along whose sides a series of operating stations are arranged, including a semi-boarding station and/or a boarding station.

[06] More specifically, according to the working method currently in use, the men's socks to be treated are put and stretched on the appropriate boarding shapes by one or more operators, at a loading station. In particular, the boarding shapes carried by the transport devices pass stepwise in front of the operator who puts each sock on a respective boarding shape.

[07] During the step of putting on the socks, the boarding shapes have a variable and undefined temperature, in any case generally it is comprised between 20° and 70° C. In fact, higher temperatures would be very problematic for the safety of the operator.

[08] The variability of the temperature of the boarding shapes, during the step of putting on the socks, depends on various factors, such as in particular the operating speed of the apparatus or the more or less rapid time of the work cycle, as well as the pressure and temperature parameters of the following work steps, as specified below. In fact, each work cycle may require different times, for example 3 seconds or higher values, depending on the type of socks to be treated.

[09] The socks put on the boarding shapes are subjected to a thermal boarding by superheated steam, at a boarding station, in which the socks are inserted into a boarding chamber arranged in line according to the direction of travel stepwise of the transport devices and supplied with pressurized steam. This boarding chamber is also called an autoclave in the specific sector.

[10] Upon exiting the boarding autoclave, the socks put on the shapes are introduced into a drying oven to eliminate residual condensation left on the yarn of the socks and on the shapes.

[11] Finally, the socks are extracted from the shapes, manually or by automatic systems, so as to be sent to the following packaging steps.

[12] As known in the art, the autoclave is made up of a pair of opposed metal shells of large thickness, adapted to automatically tighten around the boarding shapes (see Figures 9A, 10A better described below). Inside the autoclave, after the shells have been closed, superheated steam is supplied for a specific time, necessary to perform the thermal boarding.

[13] The relative pressure reached inside the autoclave, during the thermal boarding, is always not less than 1 bar (14.5 psi); this pressure corresponds to a temperature not lower than 120° C. Normally the maximum pressure used in the boarding phase inside the autoclave is equal for example to about 1.5 bar (21.8 psi), which corresponds to a temperature of 127.62° C. Pressure and therefore temperature values significantly higher than these are generally not achievable in the known art, as they would require a time for introducing the pressurized steam into the autoclave that is incompatible with the normal duration of the operating cycle, on which obviously depends the productivity of the apparatus. In the known art, the time of injection of pressurized steam inside the autoclave is about 1.5 sec. for example, which is compatible with an operating cycle duration of about 3 sec.

[14] It should be noted that, in the known art, the shells of the autoclave are made by means of a casting of cast iron or thick steel. This thickness must be able to withstand the thrust generated by the pressure of the superheated steam introduced into the autoclave. The shells of the autoclave are normally provided with hooks, on the external vertical sides, in order to withstand the thrust created by the pressure of the steam inside the boarding chamber where the socks inserted on the shapes are arranged.

[15] More specifically, the autoclave usually consists of a pair of opposing shells of great thickness, having for example a rectangular profile, movable with respect to each other between an open position and a closed position, in which they are adapted to define a boarding chamber having a relatively large internal volume. The boarding chamber is in fact capable of containing, during the boarding step, a pair of shapes carried simultaneously stepwise by a single transport device. At least one of said shells peripherally has the seat for housing a gasket suitable for ensuring the hermetic closure of the boarding chamber during the step of treating the socks with pressurized steam.

[16] The pressurized steam is introduced into the boarding chamber through an inlet hole and is discharged through an outlet hole, at the end of the boarding step. The inlet and outlet holes are controlled by respective pneumatic valves. It should be noted that, in order to avoid damage to the fabric of the socks due to the direct jet of pressurized steam, the use of special deflectors is usually provided at the inlet valve. However, this necessarily entails a further increase of the internal volume of the boarding chamber.

[17] A drawback complained of in the use of known apparatuses for heat setting men's socks consists of a very high consumption of pressurized steam. This high steam consumption is determined both by the high internal volume of the boarding chamber, which must be filled with pressurized steam and then emptied at each boarding cycle, and by the fact that the insertion of pressurized steam inside the same boarding chamber continues until the shapes and walls of the shells have reached the temperature corresponding to the set working pressure.

[18] It should be noted that, at the end of each operating cycle, the opening of the autoclave causes a sudden decrease in the temperature of the internal walls of the shells. The introduction of superheated steam inside the autoclave, during the boarding step, must therefore bring the shell walls back to the temperature corresponding to the set working pressure.

[19] Obviously, due to the large thickness of the walls, the autoclave shells absorb a proportionally high thermal energy to reach the temperature corresponding to the set working pressure at each operating cycle.

[20] Another drawback complained of in the known art is given by the fact that at the end of the boarding step the high amount of superheated steam inserted into the autoclave inevitably produces a considerable amount of condensation. The steam collected in the boarding chamber at the end of the boarding step is discharged, through a special pipe, into the water supply.

[21] Ultimately, heat setting of men's socks involves, according to the technique currently in use, a very high consumption of superheated steam, with a cost that is necessarily reflected in the final cost of the products. It should be pointed out that, since these are generally consumer products, a reduction in the production costs of men's socks is essential.

Disclosure

[22] The aim of the present invention is to solve the aforementioned problems, devising an apparatus that allows to optimally carry out the finishing of men's socks and the like, in particular ensuring a very limited consumption of steam under pressure.

[23] As part of this aim, a further object of the present invention is to provide an apparatus which substantially allows a total recovery of the residual steam at the end of the finishing phase.

[24] Another object of the present invention is to provide an apparatus that allows to obtain a significant reduction in the production costs of textile articles.

[25] A still further purpose of the invention is to provide an apparatus that avoids damage to the fabric of the socks during the step of boarding with pressurized steam.

[26] An even further object of the invention is to provide an apparatus with a simple constructive and functional conception, with reliable operation, versatile use, and which is relatively unexpensive.

[27] The aforementioned objects are achieved, according to the present invention, by the apparatus for finishing men's socks and the like according to claim 1.

[28] According to the present invention, the apparatus comprises a boarding station comprising at least one boarding chamber defined by a pair of shells between which a flattened space adapted to contain a single shape bearing a put on and stretched men's sock to be treated may be enclosed, in an operative boarding step.

[29] Preferably, said boarding station comprises a first and a second boarding chamber arranged in series and each adapted to contain a said single shape.

[30] Advantageously, said flattened space is shaped so as to surround said single shape.

[31] Preferably, said boarding chamber consists of a pair of shells of stainless sheet steel.

[32] Preferably, said shells of stainless sheet steel have sealing means, along the edge, designed to define the thickness of said flattened space enclosed in the chamber.

[33] Preferably, said sealing means comprise a gasket applied to a first shell of said boarding chamber in such a way as to peripherally surround the entire profile of the same boarding chamber.

[34] Preferably, said gasket is adapted to define the thickness of said flattened space enclosed in said boarding chamber.

[35] Preferably, said gasket is held along the external profile of said first shell of the boarding chamber by means of a side element attached to the same first shell.

[36] Preferably, said side element comprises a strip shaped according to the external profile of said first shell of the boarding chamber and adapted to be associated with an external edge of said gasket through boarding means which cross the same external edge of the gasket.

[37] It should be noted that said flattened space enclosed between the shells of the boarding chamber has a very small volume, and more specifically the minimum possible volume in relation to the dimensions of the single shape contained in the boarding chamber. In practice, this volume is limited to the space necessary to enclose a single shape. It has been verified that the overall internal volume of the pair of single boarding chambers of the boarding station according to the present invention is about 14 times lower than the internal volume of the boarding chamber of an autoclave made according to the known art. For example, this internal volume is suitably equal to about 750 cm3 for each boarding chamber, compared to a volume of about 21 ,000 cm3 of the boarding chamber of an autoclave known in the art.

[38] Due to the very small volume of the boarding chamber, a proportionately shorter time is sufficient to complete the insertion of the superheated steam inside the boarding chambers at the desired pressure and temperature. For example, the inlet of superheated steam for a time of about 0.3 sec. permits to reach a pressure of about 4 bar and a corresponding temperature of about 150° C inside the boarding chambers.

[39] According to another aspect of the invention, said boarding chamber is fed with superheated steam produced by an energy-efficient electric steam generator, carried on board of the apparatus.

[40] Advantageously, said electric steam generator has a maximum rated power of about 6 kW.

[41] Said electric steam generator is capable of producing 8 kg/h of steam at said maximum nominal power of about 6 kW.

[42] Advantageously, said electric steam generator is adapted to introduce superheated steam into said boarding chamber at high pressure, for example at a pressure of about 4 bar, thus reaching a corresponding temperature of about 150° C inside the boarding chamber.

[43] According to a preferred embodiment of the invention, the apparatus comprises a pair of energy-efficient electric steam generators, carried on board of the apparatus, each suitable for supplying with superheated steam a respective boarding chamber of said boarding station.

[44] Advantageously, said first shell of the boarding chamber has a pair of holes controlled, on opening and closing, by respective electromagnetic valves respectively for introducing the superheated steam inside said boarding chamber and for discharging the residual steam at the end of the boarding step.

[45] Advantageously, said hole for discharging residual steam is placed in communication with a water tank, where the same residual steam mixes with makeup water, supplied from the water supply network.

[46] Preferably, said makeup water is supplied to said water tank through a water softener device, in order to feed the steam generators with suitably treated water, free for example of limestone, oxides and the like.

[47] Therefore, according to a prerogative of the invention, the apparatus basically allows a total recovery of the residual steam at the end of the finishing step. It has been verified that the steam recovered in this way is equal to about 50% of the steam introduced into the boarding chambers for heat setting the socks.

[48] The apparatus according to the invention includes a frame forming a work surface developed on a substantially horizontal plane, on which a closed path is defined along whose sides a series of operating stations are arranged.

[49] The apparatus includes a plurality of transport devices designed to move at least one respective shape on which the men's socks to be treated are inserted, in use.

[50] Said transport devices are independent of each other.

[51] Said transport devices are associated with handling means adapted to drive the same transport devices stepwise along a closed path.

[52] Preferably, said transport devices respectively comprise a support member with which a pair of shapes, arranged coplanar, are made integral, in a removable manner.

[53] Preferably, said boarding chamber consists of a pair of opposing shells adapted to be tightened by a closing device on said shapes transferred stepwise by said transport devices inside the boarding chamber.

[54] Preferably, said shells are held by respective frames hinged below said work surface on axes arranged longitudinally to the direction of travel of said transport devices, so as to be adapted to oscillate between an open position and a closed position of said boarding chambers.

[55] Preferably, said closing device comprises a connecting rod and crank control mechanism, adapted to synchronously control the movement of said frames which hold said shells.

[56] The present invention also relates to a method for finishing men's socks and the like, comprising the steps of a. actuating stepwise, along a closed path, a plurality of transport devices adapted to bring in movement at least one shape on which the men's socks to be treated are inserted, in use; b. bringing each shape in succession inside a boarding chamber arranged in line along said closed path, according to the direction of travel of said transport devices, and defined by a pair of shells between which a flattened space capable of containing a single shape may be enclosed, in a operative step of boarding; c. closing said shells of the boarding chamber; d. introducing superheated steam inside said boarding chamber for a specified period; e. maintaining the closure of said shells of the boarding chamber until the predetermined boarding cycle is completed.

[57] Advantageously, the method for finishing men's socks comprises the further steps of f. discharging the residual steam from said boarding chamber towards means for recovering the same residual steam; g. opening said shells of the boarding chamber for extracting said shape from said boarding chamber.

[58] Preferably, the method provides for introducing superheated steam inside said boarding chamber for a time of about 0.3 sec. at a pressure of about 4 bar and a corresponding temperature of about 150° C.

Description of drawings

[59] The details of the invention will become more evident from the detailed description of a preferred embodiment of the apparatus for finishing textile articles according to the invention, illustrated as a non-limitative example in the accompanying drawings, wherein: Figures 1 and 2 are a perspective view of an apparatus for finishing men's socks, respectively from the front and rear sides;

Figures 3 and 4 are respectively a front view and a side view of a pair of boarding shapes; Figure 5 is a longitudinal section view of a boarding shape inside a boarding chamber of the boarding station;

Figure 6 is a side view of said boarding station;

Figures 7 and 8 are an internal front view of said boarding chambers of the boarding station, respectively from the side of said first shells and said second shells;

Figure 9 is a front view of said pair of boarding shapes in the configuration of insertion inside the respective boarding chambers;

Figure 10 is a cross-sectional view of said pair of boarding shapes in said configuration of insertion inside the respective boarding chambers;

Figures 9A and 10A are respectively a front view and a cross-sectional view of a pair of boarding shapes in the configuration of insertion inside the boarding chamber of a boarding station according to the known art;

Figure 11 is a perspective view of the closing device of said boarding chambers. Description of embodiments of the invention

[60] With particular reference to these figures, 1 indicates the apparatus for finishing men's socks and similar textile articles, such as the so-called ankle socks. The apparatus 1 is provided with a frame 2 which forms a work surface 3 developed on a substantially horizontal plane. A substantially polygonal closed path is defined on the work surface 3 along whose sides the various operating stations of the apparatus are arranged.

[61] A plurality of shapes 4 are guided stepwise along said polygonal path, on which the socks to be treated in said operating stations are put, in use. In practice, in the shown case, this polygonal path consists of a rectangle defined by the sides of the frame. Obviously, it is possible to provide that said closed path has a different shape from the represented one.

[62] In particular, the apparatus 1 includes a station for loading the socks to be treated on the shapes, manually or by means of an automatic loading apparatus not shown in the drawings; a station for boarding by means of superheated steam; a station for drying the treated socks; an output station of the socks.

[63] The shapes 4 are made up of an aluminum template, preferably black in color. In particular, the shapes 4 consist of a solid template shaping the profile of the foot and are mounted in pairs, in a vertical position, on transport devices 5 (see Figures 3 and 4). In a known way, the shapes 4 have different dimensions according to the size of the socks to be made, from the child to the adult.

[64] The transport devices 5 respectively comprise a support member 6 with which a pair of shapes 4, arranged coplanar, is made integral, in a removable manner. The support member 6 is mounted on special runners 7, sliding on guide means associated with the plane 3 of the apparatus. The transport devices 5 may be operated synchronously by suitable handling means 8 associated with the apparatus 1.

[65] The socks are put on the respective shapes 4 at a loading station where one or more operators work(s). Alternatively, it is possible to provide that the socks are automatically put on the shapes by means of a loading apparatus, in a manner known in the art.

[66] According to the present invention, the boarding station 10 comprises at least one boarding chamber 11 arranged in line along said closed path, according to the direction of travel of the transport devices 5; the boarding chamber 11 is adapted to enclose, in the operative boarding step, a single shape 4.

[67] Preferably, the boarding station 10 comprises a first and a second boarding chamber 11 arranged side by side on a vertical plane longitudinal to the direction of travel of the shapes mounted on the transport devices 5 (Figure 5). The boarding chambers 11 are designed to enclose each one a single shape 4, as specified below. Therefore, essentially, the pair of boarding chambers 11 arranged side by side is suitable for receiving the pair of shapes 4 mounted on a single transport device 5 feeding stepwise at each operating cycle, so as to simultaneously carry out the thermal boarding of the pair of socks put on said pair of shapes 4.

[68] Each boarding chamber 11 is defined by a pair of opposing shells 12, movable with respect to each other between an open position and a closed position of the boarding chamber 11. Preferably, the shells 12 are made of stainless steel plates, suitably shaped, having respective sealing means 13, 14 along the edge (see Figures 6, 7 and 8). For example, these stainless steel plates have a thickness of 1.2 mm. Advantageously, said stainless steel plates are shaped so as to surround said single shape 4.

[69] Sealing means 13, 14 are arranged on the side of the stainless steel plates facing the inside of the boarding chamber 11. In particular, a first shell 12 of the boarding chamber 11, facing the outside of the apparatus, has a gasket 13 applied peripherally around the entire profile of the same boarding chamber 11. The gasket 13 is held in abutment along the external profile of the first shell 12 of the boarding chamber 11 in contrast to a side element 15 shaped according to the external profile of the same shell 12. The gasket 13 and the side element 15 are constrained to the shell 12 of the boarding chamber 11 by suitable fixing means, for example a series of regularly spaced rivets 16.

[70] The second shell 12 of the boarding chamber 11, facing towards the inside of the apparatus, has a further gasket 14 applied thereon, which affects only the lower part of the boarding chamber 11 , so as to seal the shape 4, in the closed position of the same boarding chamber 11. The further gasket 14 is similarly held in abutment along the external profile of the second shell 12 of the boarding chamber 11 contrasting a relative side element 17 shaped according to the external profile of the same shell 12. The side elements 15, 17 are for example made of sheet metal elements.

[71] In practice, a flattened space capable of enclosing the single shape 4 may be defined between each pair of shells 12, in said open position of the boarding chamber 11. The sealing gasket 13 applied along the edge of the first shell 12 essentially defines the thickness of said flattened space enclosed in the boarding chamber 11. In practice, the volume of the boarding chamber 11 is determined only by the thickness of the sealing gasket 13.

[72] It is easy to recognize that this flattened space has a very small volume, and more specifically the minimum possible volume in relation to the dimensions of the single shape 4 contained in the boarding chamber 11. In practice, this volume is limited to the space necessary to enclose the single shape 4. For example, this volume is conveniently equal to about 750 cm3 for each boarding chamber 11.

[73] The first shell 12, facing the outside of the apparatus, has a pair of holes 18, 19, the upper and the lower, respectively for introducing the superheated steam inside the boarding chamber 11 and for discharging the residual steam at the end of the boarding step. The steam inlet and outlet holes 18, 19 are suitably controlled, on opening and closure, by respective electromagnetic valves.

[74] The boarding chambers 11 are fed with superheated steam produced by respective energy-efficient electric steam generators 20, carried on board of the apparatus. The steam generators 20 are preferably mounted above the work surface 3 of the apparatus, at a short distance from the boarding station 10.

[75] In particular, each steam generator 20 has for example a rated power of 6 kW, capable of producing 8 kg/h of steam. In use, the superheated steam is suitably introduced into the boarding chambers 11 at a pressure of about 4 bar (58 psi), with a corresponding temperature of about 150° C (302° F).

[76] The steam generators 20 are powered by a water tank 21 , fed in turn by a treatment device, adapted to prevent the formation of limestone and oxides. This treatment device is conveniently made up of a softening device known in the art. The water tank 21 is connected to the water supply through said softener device. It should be noted that the use of treated water in the system, in addition to preserving the steam generators 20, improves the quality of the produced socks.

[77] The water tank 21 is also connected to the drain holes 19 of the boarding chambers 11 , for the recovery of residual steam at the end of each boarding step, as specified below.

[78] The shells 12 of the boarding chambers 11 are held by a respective frame 22. The shells 12 are fixed to the frame 22, in a removable manner, by suitable fixing means distributed along the periphery of the stainless steel sheet plates, for simplicity not shown. Appropriately, a layer of insulating material 24 is interposed between each shell 12 and the respective frame 22.

[79] In particular, the boarding station 10 comprises a pair of opposite frames 22, each holding a pair of shells 12 cooperating with the opposite pair of shells 12 to define said boarding chambers 11 arranged side by side on the vertical plane longitudinal to the direction of travel of the transport devices 5.

[80] The frames 22 holding the shells 12 are hinged below the frame 2 of the apparatus on a respective axis 23 arranged longitudinally to the direction of travel of the shapes 4, so that they oscillate between said open position and said closed position of the boarding chambers 11.

[81] The shells 12 may be tightened on the shapes 4 transferred stepwise inside the boarding chambers 11 by a closing device 30 associated with the frames 22 (see Figure 11). The closing device 30 comprises a connecting rod and crank control mechanism 31, adapted to synchronously control the movement of the frames 22 holding the shells 12. More precisely, the control mechanism 31 consists of a crank member 32 articulated to a connecting rod member 33. The crank member 32 is rotating on a shaft parallel to the axes 23 of the frames 22, driven by a motor member 34.

[82] Following the rotation of the crank member 32, the connecting rod member 33 is movable between a raised top dead center configuration and a lowered bottom dead center configuration. The connecting rod member 33 may transmit motion to a double pair of tie rods 35, 36 hinged respectively to the frames 22. In particular, the tie rods 35, 36 are hinged, on the opposite side to that of articulation to the frames 22, at the opposite ends of a link 37 rotated by a shaft 38 which takes the motion from the connecting rod 33.

[83] Basically, the reverse reciprocating movement imposed on the tie rods 35, 36 by the connecting rod and crank control mechanism 31 of the closing device 30 determines the oscillating movement of the frames 22 between said open position and said closing position of the boarding chambers 11. [84] The operation of the apparatus for finishing men's socks according to the present invention is easily understood from the above description.

[85] The men's socks to be treated are put, manually or by means of an automatic loading device, on the shape 4, which is in the loading station. In the illustrated case, for example, at each stop at the loading station a pair of socks is put on the pair of shapes 4 carried by a single transport device 5.

[86] After putting the socks on the shape 4, the stepwise feeding is operated, which makes the transport devices 5 sequentially engage the boarding station 10. In particular, the transport devices 5 carry the individual shapes 4 in succession inside the respective boarding chambers 11 , where the heat treatment of the socks with superheated steam takes place. To this end, after the entry and stopping of a single transport device 5 inside the boarding station 10, the closing device 30 commands the closing of the opposing shells 12 of the boarding chambers 11; the shells 12 are hermetically tightened on the forms 4, to allow the introduction of the superheated steam into the chamber.

[87] Conveniently, the support member 6 of the shapes 4 on the transport device 5 has a central hole 9 which, at the boarding station 10, allows the beam emitted by an emitter to coincide with a suitable receptor, so as to ensure the perfect centering of each shape 4 inside the relative boarding chamber 11.

[88] At this point the opening of the inlet holes 18 of the shells 12 is commanded, through the respective electromagnetic valves, to introduce superheated steam inside each boarding chamber 11. Advantageously, the superheated steam introduced into the boarding chambers 11 has a high pressure, for example 4 bar, which corresponds to a temperature of 152° C. The introduction of superheated steam takes place for a predetermined time, for example equal to 0.3 sec.

[89] After the superheated steam is introduced, the shells 12 of the boarding chambers 11 are kept closed until the predetermined boarding cycle is completed. The opening of the outlet holes 19 of the shells 12 is then controlled, through the respective electromagnetic valves, to discharge the residual steam from each boarding chamber 11. This residual steam is conveyed to the water tank 21, where it mixes with the makeup water fed from the water supply network. The makeup water fed from the water supply network, before entering the water tank 21 , passes through the softener device, in order to feed the steam generators 20 with suitably treated water, free of limescale, oxides and the like. In practice, the steam generators 20 are substantially fed with distilled water.

[90] At the end of the thermal boarding, the shells 12 of the boarding chambers 11 are opened to let the shapes 4 out, while in a suitable phase relationship a subsequent transport device 5 carries another pair of shapes 4 inside the respective boarding chambers 11.

[91] It should be noted that the use of black forms 4 let the forms to be kept warmer, facilitating the drying of the socks as they come out of the boarding chambers 11.

[92] The apparatus in question thus achieves the purpose of optimally operating the finishing of textile items such as men's socks and the like, in particular ensuring the lowest possible energy consumption.

[93] This result is achieved thanks to the inventive idea of providing a boarding station 10 comprising a pair of boarding chambers 11 arranged in series capable each one of containing a single shape 4 holding the sock to be treated. In particular, these boarding chambers 11 each suitable for containing a single shape 4 respectively define internally a flattened space shaped so as to surround said single shape 4.

[94] The very limited volume of this internal space of the boarding chambers 11 is substantially determined by the thickness of the sealing gasket 13 applied along the edge of the first shell 12 and is therefore such as to require the introduction of an equally minimal quantity of superheated steam at each operating cycle.

[95] Figures 9, 10 and 9A, 10A compare, by way of example, the dimensions of the single boarding chambers 11 of the boarding station 10 according to the present invention with the dimensions of the boarding chamber 11A defined between the shells 12A of a conventional autoclave, made according to the known art, in the configuration of inserting a pair of shapes 4 inside said boarding chambers.

[96] It has been verified that the internal volume of the boarding chamber 11 A of the autoclave made according to the known art is approximately 14 times the total internal volume of the single boarding chambers 11 of the boarding station 10 according to the present invention.

[97] More specifically, according to the present invention, the internal volume of each boarding chamber 11 is equal to about 750 cm3, compared to a volume of about 21 ,000 cm3 of the boarding chamber of a known type of autoclave. In practice, in fact, the area of the single boarding chambers 11 is about 60% less than the area of the boarding chamber 11A of the conventional autoclaves used in the apparatuses known in the art, defined by the rectangular surface of the shells 12A (Figure 9A); in turn, the thickness of the boarding chambers 11 is equal to approximately one fifth of the thickness of the boarding chamber 11 A of said known autoclaves (Figure 10A).

[98] According to a prerogative of the invention, the boarding chambers 11 are shaped so as to surround the individual shapes 4. Due to the resulting limited surface, inside each of said boarding chambers 11 , with the same set pressure of steam, the thrust acting on the opposite walls is much lower than that in the autoclave of the apparatus known in the art. It is therefore possible to use a stainless steel sheet having a reduced thickness for making the shells 12 of the boarding chambers 11 , for example not exceeding 2 mm and advantageously approximately 1.2 mm, without causing bending of the walls of these boarding chambers 11.

[99] The reduction in the width and thickness of the shells 12 naturally involves a corresponding reduction in the mass of the walls of the boarding chambers 11. In particular, this mass is suitably less than 10 kg for each of said boarding chambers 11 , compared to a mass greater than 100 kg for the autoclave of the apparatuses known in the art. The walls of the boarding chambers 11 can therefore reach the temperature corresponding to the set working pressure more quickly at each operating cycle.

[100] The strong reduction in steam consumption has the further advantage of using an energy- efficient electric steam generator 20, to feed each boarding chamber 11 with superheated steam. For example, it is possible to provide for the use of a steam generator 20 having a maximum power of 6 kW, capable of producing 8 kg/h of steam. Advantageously, due to its small size, this steam generator 20 can be installed on board of the same apparatus, for example at a short distance from the boarding station 10. This allows the electric boiler to be connected to the boarding chambers 11 by means of a pipe of reduced length, so as to minimize any pressure loss.

[101] This avoids the need to connect the apparatus to a centralized steam production plant within the factory, making the apparatus completely autonomous.

[102] According to a prerogative of the invention, the superheated steam is suitably introduced into the boarding chambers 11 by the electric steam generators 20 at high pressure, for example a pressure of about 4 bar, thus reaching inside the boarding chambers 11 a corresponding temperature of about 150° C. Due to the very small volume of the boarding chambers 11, the time required for introducing superheated steam inside the boarding chambers 11 is also very short. The introduction of the superheated steam inside the boarding chambers 11 is completed for example in about 0.3 sec., in comparison with about 1.5 sec. necessary in the autoclave of known types of apparatuses.

[103] In addition, the finishing of men's socks at a high temperature, about 150° C, has the effect of improving the quality of the product, as the yarn is blocked, avoiding the curling of the toe of the socks, which is frequent in the known art.

[104] Another advantage offered by this solution is given by the fact that the reduced dimensions of the boarding chambers 11 and the consequent lower quantity of steam under pressure inside them determine a reduction in the force necessary for sealing the boarding chambers 11. Consequently, the boarding station 10 does not require the presence of the clamping hooks of the shells 12 usually provided in the autoclave of known apparatuses.

[105] According to another prerogative of the invention, the apparatus basically allows a total recovery of the residual steam at the end of the finishing step. In fact, the steam coming out of the lower holes 19 of the shells 12 of the boarding chambers 11, at a relatively high temperature, is conveyed to the water tank 21 , where it mixes with the makeup water fed by the water supply network. In particular, it has been verified that the steam recovered in this way is equal to about 50% of the steam introduced into the boarding chambers 11 to carry out thermal treatment of the socks.

[106] Another advantage offered by the invention is given by the fact that the introduction of the superheated steam inside the boarding chambers 11 and the following discharge can take place through the holes 18, 19 of limited diameter. In fact, since the amount of superheated steam to be introduced into the boarding chamber 11 is reduced, the holes 18, 19 can have a correspondingly reduced diameter with respect to the known art, for example less than 10 mm. In particular, the inlet hole 18 of the superheated steam inside the boarding chamber 11 can have a diameter of less than 5 mm and advantageously approximately 4 mm. This makes it possible to control the opening and closing, that is, the steam inlet and discharge steps, by means of respective electromagnetic valves, faster than the pneumatic valves used in the known art. In particular, as mentioned, the introduction of superheated steam inside the boarding chambers 11 can be completed for example in about 0.3 sec., compared to about 1.5 sec. necessary in the autoclave of known apparatuses. This also avoids the need to connect the apparatus to a compressed air supply, as happens using pneumatic valves.

[107] A further advantage of the invention is the fact that said electromagnetic valves are designed to introduce steam in a radial direction into the flattened space enclosed between the shells 12, through the holes 18 placed in the upper position in the boarding chamber 11. This ensures that the superheated steam introduced into the boarding chamber 11 does not directly hit the socks inserted on the last 4, thus avoiding possible damage to the fabric.

[108] It should be noted that in the known art, to avoid said damage to the fabric of the socks, the use of a special steam diffuser 25A inside the boarding chamber is usually provided, as shown in Figure 10A. However, this necessarily contributes to the increase in the internal volume of the volume of the boarding chamber which, conversely, the present invention can make the minimum possible.

[109] Another advantage offered by the invention is the fact that the shells 12 that make up each boarding chamber 11 are removable and therefore interchangeable according to the type of socks, that is they can be easily replaced depending, for example, on the size of the treated socks. In this way, the internal volume of the boarding chamber 11 is always the minimum possible even when the size of the treated socks varies and therefore the minimum consumption of steam is always ensured, contrary to what happens in traditional apparatuses in which the autoclave is fixed and therefore it is necessarily dimensioned in relation to the larger shapes. [110] Ultimately, the apparatus according to the invention allows to significantly reduce the production cost of the textile items. In particular, it has been seen that the reduction in the cost of products can reach 80% compared to the known apparatuses.

[111] The apparatus described by way of example is subject to numerous modifications and variations according to the different needs.

[112] In the practical embodiment of the invention, the materials used, as well as the shape and the dimensions, may be modified depending on requirements.

[113] Should the technical features mentioned in any claim be followed by reference signs, such reference signs were included strictly with the aim of enhancing the understanding of the claims and hence they shall not be deemed restrictive in any manner whatsoever on the scope of each element identified for exemplifying purposes by such reference signs.