DEVICE AND PROCESS FOR LOCKING A TERMINAL EDGE OF A FABRIC ROLL

Abstract: It is foreseen a device used for locking a terminal edge of a fabric roll, including lock devices (7) suitable for applying adhesive labels (8), positioning members (5) including mobile bearings (5a, 5b) for a fabric roll (3) and a drive member (5c) suitable suitable for turning said roll (3) therearound, a positioning zone (2a) for a terminal edge (3a) of said fabric developping along a prefixed length between a cutting edge (3b) of said terminal edge (3a), and synchronization means (21) suitable for locating the position of said cut edge (3b) and active onto said drive member (5c) and onto said lock device (7). Further it is foressen a process including the rotation of said roll (3) in a direction suitable for winding said terminal edge (3a) and the application of adhesive labels (8) to said roll (3), these labels being forcedly supplied with a feeding speed coincident with the peripheral rotation speed of said roll (3).

Description: The present invention relates to a device and a process for locking the terminal edge of a fabric roll and it is referred to the technical field of machines used for winding fabrics and cloths in automatic manner. As it is known, the locking of the terminal edge of a fabric roll or similar material roll precedently wound onto e.g. a cylindrical cardboard element is made by some proper lock elements, using one or more lock devices. Generally the lock elements are adhesive bands that, using proper lock devices including particular feeders, are applied by adhesion to the fabric roll along a length corresponding to its whole circumference. The adhesive bands are normally fed from the lock devices by the drawing action of the rotating fabric roll after a little initial part of said adhesive bands was joined by adhesion to the fabric roll. The above mentioned technique has important drawbacks. In fact a first drawback is caused by the surface length related to the adhesive band contact. This length corresponds, for each applied band, to the whole circumference of the fabric roll. This causes the possibility of damaging the whole more external turn of the fabric roll, as generally the adhesive band causes some traces or signs onto the fabric, above all if the said fabric is soft. Further during the use it is necessary to cut the adhesive band, instead of separating it simply by detaching, using particular attention for avoiding the fabric damages, as it is not possible to find easily the band end point, overlapped to another zone thereof, and to start its removal from this position. A second important drawback is the stretch of the fabric, that is caused to the roll surface, as the adhesive band is applied onto the same roll by the drawing action of this roll, driven previously in rotation. This drawback is particularly important with soft fabrics. Both above mentioned drawbacks make often impossible to use the more external turn of the fabric roll, and this damaged turn must be rejected. It was tried to solve at least the first drawback using special strips of adhesive band, having a considerably high cost, suitable for avoiding to let traces onto the fabric, but the obtained results are not satisfactory. In this situation the technical scope of the present invention is to supply a device and a process for locking the terminal edge of a fabric roll suitable for obviating substantially the above mentioned drawbacks. Within this technical scope, an important object of the invention is to supply a device and a process in which the damages caused to the external surfaces of the fabric roll by the lock elements of the terminal edge are substantially reduced, and in which the stretches or tensions of the fabric are totally avoided, mainly in the application zones of the locking elements of the terminal edge. Another important object of the invention is to supply a device and a process in which the removal of the lock elements is easier during the use of the fabric roll. A device and a process, which correspond respectively to the preamble of independent claims 1 and 10, are known from FR-A-2 235 075. The above mentioned technical scope and the specified objects are substantially obtained by a device for locking the terminal edge of a fabric roll as described in Claim 1 and by a process for locking the terminal edge of a fabric roll as described in Claim 10. Further characteristics shall appear better by the following description of a preferred but not limited embodiment of a device and a process for locking the terminal edge of a fabric roll, that is described making reference to the annexed drawings, in which: Figure 1 shows a lateral view of the device according to the invention; Figure 2 shows a plan view of a part of the Figure 1; and Figures 3 and 4 show, in enlarged scale, the details of the device of the Figure 1. Making reference to the above mentioned figures, the device according to the invention is generally indicated by the reference number 1. It includes a seat 2, suitable for housing a fabric roll 3, showing the terminal edge 3a obtained by the cutting made by a cutting member 4 located on one side of the device 1. In pratice the cutting member 4 makes a cutting edge 3b of the fabric by truncation and it is adjacent to a winding device, located on the left side of the cutting member 4 in Fig. 1, in which the roll 3 is formed and then ejected in the direction of the seat 2, passing under the cutting member 4. The seat 2 is substantially formed by positioning members 5 of the roll 3, including a couple of mobile bearings or conveyor belts 5a and 5b and a drive member 5c. The conveyor belts 5a and 5b are laid on a cradle and the drive member 5c drives the same conveyor belts in a manner suitable for turning the fabric roll 3 around its axle by tangential drive. It is advantageously foreseen a prefixed and substantially constant peripheral speed, corresponding to the progress speed of the same conveyor belts. During the rotation, the roll 3 remains always housed within the seat 2, with its central axle being located in substantially fixed position. Before rotating the roll 3 around its axle, the terminal edge 3a engages a positioning zone 2a of the fabric having a constant length, equal to the distance between the cutting member 4 and the roll 3. A bar 6, parallel to the fabric roll 3 and mobile by approaching and moving away with respect to the roll, supports a plurality of lock devices 7, spaced with one another and positioned along the bar 6 (Figure 2) and suitable for feeding adhesive elements 8 forming adhesive labels, that are wound on a limited part of the circumference of the fabric roll 3. The guide members 9 and drive means 10, located onto the bar 6, are foreseen at the ends of said bar 6. The guide members 9 include rail elements 11, mounted substantially in radial direction with respect to the fabric roll 3 and trolley elements 12, joined to the bar 6 and sliding on the rail elements 11. The drive means 10 includes, in conjunction with an end of the bar 6, an electric motor 14, joined to the bar 6 and mobile therealong, a gear 15 keyed to a shaft 16 parallel to the bar 6 and rotating driven by the motor 14 and a rack 17 substantially directed in radial direction with respect to the fabric roll 3 and meshed with the gear 15. Each one of the above described lock devices 7 supported by the bar 6, includes (Figure 3) rewinding members 18 of a continuous support strip 19, on which the adhesive labels 8 are applied in succession and separated with one another. Each lock device 7 includes also drive elements 7a suitable for supplying by force the adhesive labels 8 at a feeding speed coinciding with the foreseen peripheral speed of the roll 3, that is the peripheral speed caused by conveyor belts 5a, 5b by means of the drive member 5c. Further, in conjunction with the lock devices 7, pressure members 20 of the labels 8 made up of rollers parallel to the fabric roll 3 and supported by spring means 20a activing in the direction of the roll 3 are provided. Further, the device 1 includes synchronization means 21 including electronic programmable logic units and connected both to the lock devices 7 and to the drive member 5c. In detail the synchronization means 21 is suitable for activating the lock devices 7 during the passage of the cutting edge 3b under the said lock devices and for this aim they include sensors, such as a finger 13 and a rotation time counter 22. The finger 13 is supported by the bar 6, joined to the electric motor 14 and directed to the roll 3 for measuring the diameter of the roll 3. The time counter 22 is joined to the drive member 5c and is suitable for surveying the rotation time of the roll 3 corresponding to the activation time of the drive member 5c. When the finger 13 causes the stop of the motor 14, the same finger supplies also the informations necessary for recognizing the measure of the diameter of fabric roll 3 and therefore it allows the calculation of the above mentioned rotation time of the roll, necessary for causing the passage of the cutting edge 3b before the lock devices 7. The running of the above described device according to the invention, that was described under the structural point of view, occurs as follows. The fabric roll 3, after being formed between proper winding cylinders, is ejected and partially unwound towards the cutting member 4 and towards the seat 2. The operation of the cutting member 4 realizes in one side of the seat 2, the cutting edge 3b that forms the end of the terminal edge 3a to be wound and fixed. The terminal edge 3a remains unwound and laid to the positioning zone 2a, and has a prefixed length, while the roll 3 is located in the seat 2 on the positioning members 5. In this situation the bar 6 is lowered until the finger 13 contacts the roll 3. In this manner the lock devices 7 are correctly positioned at a suitable operative distance from the surface of the roll 3. Further the finger 13 sends a signal for the synchronization means 21 that establishes the exact value of the diameter of the roll 3. In this manner the synchronization means 21 can calculate a time T1 necessary for rotating the roll 3 with a prefixed speed by the angle included between the contact zone of the seat 2, located approximatively on the vertical direction with respect to centre of the roll 3, and the feeding point of the adhesive labels 8. Further the synchronization means 21 stores a time T2 necessary for winding of the fabric section having a constant length included between the cutting member 4 and the above mentioned contact zone. Therefore it is foreseen that the roll 3 is wound with a constant peripheral or tangential speed as the conveyor belts 5a, 5b are driven by the drive member 5c with a substantially constant speed, and the time T2 is constant and independent from the diameter of the fabric roll 3. Also the time T1 can be calculated easily. In this manner the sum of the time T1 and time T2 supplies the total time T corresponding to the rotation of the fabric roll 3 suitable for positioning the end of the terminal edge 3a in the zone foreseen under the lock devices 7. The feeding of the adhesive labels 8 occurs at a speed coinciding with the progress speed of the conveyor belts 5a and 5b, that is also the peripheral speed of the fabric roll 3. In this manner the adhesion of the label to the fabric is made without applying any stretch on the fabric. The rollers 20 supplies a spring pressing force, suitable for guaranteeing the perfect adhesion of the label 8 to the fabric. The device 1 fulfils a process for locking the terminal edge of a fabric roll, also this being a part of the invention. This process includes the installation of the fabric roll 3 with the terminal edge 3a to be wound having a prefixed length and the positioning of lock devices 7 of the terminal edge 3a in prefixed position with respect to the fabric roll 3. In the following the fabric roll 3 is rotated in winding direction with a prefixed peripheral speed and the lock devices 7 are driven only when the cutting edge 3b of the terminal edge 3a passes under said lock devices 7. The adhesive label is applied onto the fabric roll, this label being advantageusly supplied at a speed coinciding with the peripheral rotation speed of the same fabric roll. The invention achieves important advantages. In fact the locking of the terminal edge of the fabric roll damages in a very reduced manner the external surface of the fabric, if it is made according to the invention. In fact a very reduced area is taken by the adhesive labels and the same labels are applied without stretching the fabric. Further it must be underlined that the manual removal of the adhesive labels is made easier by the visibility of the start and of the end thereof, favoured by the visual contrast with the fabric. In this manner it is also avoided the necessity of using cutting elements that can damage the underlying fabric.

Claims: 1. Device for locking the terminal edge (3a) of a web roll (3), including: a seat (2) for housing said web roll (3), at least one lock device (7) for applying adhesive elements (8) to said web roll (3) and for supplying said adhesive elements (8) onto a limited part of the circumference of said web roll (3), positioning members (5) of said web roll (3) defining at least a part of said seat (2) and including mobile bearings (5a, 5b) and a drive member (5c) for turning said web roll (3) around itself, a positioning zone (2a) for said terminal edge (3a) having a prefixed length, equal to the distance between a cutting edge (3b) of said terminal edge (3a) and said web roll (3), synchronization means (21) supplied with sensors (13, 22) for establishing the position of said cutting edge (3b), said synchronization means (21) being connected to said drive member (5c) and to said lock device (7) for causing the operation of said lock device (7) substantially during the passage of said cutting edge (3b) under said lock device (7), and said adhesive elements (8) being applied onto said web roll (3) with the force of at least one pressure member (20), characterized in that said web roll is a fabric roll (3) and said lock device (7) includes internally drive elements (7a) for supplying said adhesive elements (8) by force onto said rotating fabric roll (3) at a feeding speed coinciding with the peripheral speed of said fabric roll (3) that is turned by means of said positioning members (5). 2. Device according to Claim 1, in which said mobile bearings include conveyor belts (5a, 5b) driven by said drive member (5c) with a constant and prefixed speed for rotating said fabric roll (3) with a constant and prefixed peripheral speed. 3. Device according to Claim 2, in which said sensors (13, 22) are defined by a finger (13) for measuring the diameter of said fabric roll (3) and a time counter (22) for surveying the activation time of said drive member (5c). 4. Device according to Claim 1, in which said positioning zone (2a) of said terminal edge (3a) is situated between said fabric roll (3) and a cutting member (4) external to said positioning members (5), said cutting member (4) makes said cutting edge (3b) by truncating the fabric of said fabric roll (3). 5. Device according to Claim 1, in which said adhesive elements (8) are defined by adhesive labels, said adhesive labels being mounted in succession among one another onto a continuous support strip (19) and said lock device (7) including rewinding members (18) of said support strip (19). 6. Device according to Claim 1, in which at least one of said lock devices (7) is mounted onto a bar (6) parallel to said fabric roll (3) and in which guide members (9) and drive means (10) of said bar (6) are provided at the end thereof, for moving said bar (6) approaching and moving away with respect to said fabric roll (3). 7. Device according to Claim 6, in which said guide members (9) include rail elements (11), located substantially in radial direction with respect to said fabric roll (3) and trolley elements (12) joined to said bar (6) and sliding onto said rail elements (11). 8. Device according to Claim 6, in which said drive means (10) includes an electric motor (14) joined to said bar (6) and mobile therealong, a gear (15) rotatably driven by means of said electric motor (14) and mobile in translation therewith, and a rack (17) fixed in position substantially directed in radial direction with respect to said fabric roll (3), said rack (17) being meshed with said gear (15) and said electric motor (14) being controlled for being stopped by said finger (13) supported by said bar (6) and directed towards said fabric roll (3). 9. Device according to Claim 6, in which said pressure member (20) for said adhesive elements (8) is a roller located parallel to said fabric roll (3) and supported by spring means (20a) acting in the direction of said fabric roll (3), said spring means (20a) being connected to said bar (6). 10. Process for locking the terminal edge (3a) of a web roll (3), including: the rotation of said web roll (3) in a direction necessary for winding said terminal edge (3a), the actuation of a lock device (7) for applying an adhesive element (8) to said terminal edge (3a) only when a cutting edge (3b) of said terminal edge (3a) passes under said lock device (7), and the application with the force of at least one pressure member (20) onto a limited part of the circumference of said rotating web roll (3) of said adhesive element (8), characterized in that said web roll is a fabric roll (3) and said adhesive element (8) is supplied by force onto said rotating fabric roll (3) at a feeding speed coinciding with the peripheral rotation speed of said fabric roll (3). 11. Process according to Claim 10, in which both said terminal edge (3a) and said lock device (7) are located in prefixed positions, and said lock device (7) is actuated, while said fabric roll (3) is driven in rotation. 12. Process according to Claim 11, in which said fabric roll (3) is arranged with a section still unwound having a prefixed length, afterwards said fabric roll (3) is rotated in winding direction with a substantially constant and prefixed peripheral speed, and the operation of said lock device (7) is started after a time corresponding to the rotation of said fabric roll (3) necessary for positioning the end of said section still unwound in the zone under said lock device (7).

Inventors: GASTOLDI, PAOLINO
Applicants: LA MECCANICA COSTRUZIONE  MACCHINE TESSILI S.P.A.
Application year: 1989
Main classification: B65H19
IPC codes: B65H19