FR2692566A3 - Joining machine for linking ends of rolls of material - includes guides and adhesive tape dispensing device forming automatic joint between ends of material - Google Patents

Abstract

The device comprises two supports (4, 5) which momentarily immobilise the two sections of material so that the edges abut side by side. A further support is provided for an adhesive band carrier (10) and a cutting tool (8, 9) which moves vertically and cooperates with stops (6, 7). The two supports are able to move in order to allow the two material sections to be brought to the correct position for joining. The presence of the material is detected by photodetectors (3) as it passes over a roller (2). USE - Automatic joining of lengths of material, esp. plastic used e.g. in packaging of pharmaceutical pills in blister pack.

Description

 The invention relates to a device for automatically joining the final section of a first sheet of material, mobile and sent to a working process arranged downstream, with the initial section of a second sheet of material being in the standby position. , by avoiding an interruption in the working process by forming a reserve of material ply from the final section of the first ply of material, this device comprising, on the one hand, two supports which support the two plies of material and momentarily immobilize them and which, in a position where the ends of the plies of material are abutted edge to edge, constitute a counter-support for an adhesive strip holder and, on the other hand, a device for cutting off the ends of the plies of material which is vertically movable and whose cutting surfaces cooperate with cutting edges made on the supports, the two sections of the plies of material being hand held on these supports and being joined together, in the form of a continuous sheet, by means of an adhesive strip disposed on the adhesive strip holder.

 Industrial production undergoes many working processes, for example the continuous packaging of pharmaceutical products by means of what is known as packaging in blister packs or in blister packs, in which a sheet of material in film of material plastic, paper or similar material must be sent continuously to the work process. Since the tablecloths which can be used for this purpose are supplied in rolls, each time a reserve of tablecloth must be kept ready and connected, following the previously treated tablecloth, in a sufficiently rapid manner so that, as a result, there is only a short interruption of the work process, the ideal being, if possible, a total absence of interruption.

 In a known device of this type (DE-OS 36 14 221), the front end of a second sheet to be connected is brought into the standby position by being arranged in overlap so as to project beyond a first cutting edge of its support and it is held in this position by a clamping rod. The first associated ply is also brought above a lower blade so that, when it reaches its final section, the latter overlaps the cutting edge of this lower blade while hanging beyond. The two end sections are immobilized with respect to the cutting edges, for one by means of the said clamping rod and for the other by means of a pair of cylinders arranged next to the lower blade in the direction displacement of the tablecloth. The end sections of ply are brought one on the other so as to be edge to edge and an adhesive strip is applied to the connection zone of these ends of ply.

We can then continue to move the glued sheet.

 In this known device, a functional drawback, limiting the working speed, lies in the fact that the trajectory of movement of the support relative to the lower blade is arranged along a curve. In addition, the fact that a reserve of ply must be permanently provided in the outgoing ply of material constitutes a drawback for obtaining a precise control of the ply.

 The object of the invention is to provide a device of the type indicated in the preamble, of the simplest possible structural design, which allows the two ends of the ply to be joined together while the working process is taking place, of a so that there is no delay in this process.

 According to the invention, this object is achieved by the fact that the supports are guided so as to be in a common plane parallel to the plane of movement of the sheets and to be able to be moved inside this plane, in one direction and in the other, between a position in which they are in abutment against one another by their cutting edges and a position in which they coincide with the cutting surfaces of the cutting device so as to carry out cutting, the fact that the adhesive strip holder is mounted so that it can be moved vertically in translation, with respect to the sheets of material, above the position in which the cutting edges of the supports are in abutment one on the other, and the fact that downstream of the supports and upstream of a next processing station in the direction of movement of the first sheet of material, there is provided a drive device for transporting the ply, used to form the reserve from the outgoing end constituting the end of the first ply, there the presence of the end of the latter being detected by a sensor disposed upstream of the supports in the direction of movement and being drawn from so as to form the reserve at an increased forward speed after reception of the signal from this sensor by the drive device.

 Advantageously, it can be provided that above the supports, there are arranged two counter-supports which are driven so that they can be moved vertically and horizontally and whose horizontal feed movements are adapted synchronously the movements of the supports.

According to a first particular embodiment of the invention,
The drive arrangement, used for transporting the sheet, may comprise a pair of jaws disposed on either side of the plane of movement of the first sheet and movable horizontally, the lower jaw serving as a fixed abutment for the jaw which is made so that it can be moved vertically. According to a second particular embodiment of
The invention, it can be provided that the drive arrangement, used for transporting the sheet, is produced in the form of a pair of driven cylinders which is provided on either side of the plane of movement of the sheet. .

 Advantageously, in order to constitute the reserve of material ply, provision may be made for a return arrangement to cylinders which is subjected to an elastic prestress.

 Preferably, the sensors can be photoelectric cells.

The device according to the invention combines in itself the combination of the following advantages:
- it is in a separate and automatic way that the two ends of the ply are cut exactly at right angles and joined,
- the ends of the ply are brought one on the other edge to edge and joined by means of a thin adhesive strip which is always applied on the same side of the ply surfaces,
- overlapping of the ends of the ply is safely avoided in the junction area,
a reserve of ply is formed by increasing the advance movement of the end of the outgoing ply,
- thanks to the formation of a reserve, the working process can be continued at rates adjustable in a different way during the joining of the sheets,
- the rollers carrying the plies can always be placed in the same position on fixed axes and
- the end sections of the sheet which are cut fall freely downwards and therefore do not interfere with the rest of the work process.

Other characteristics and advantages of the invention will emerge from the description which follows, by way of nonlimiting example and with reference to the appended drawings in which:
Figures 1 to 6 show an embodiment of a device according to the invention in different phases of the junction of the plies of material and
FIG. 7 illustrates the application of an adhesive strip on the joining section of the two ends of the ply.

 As shown in FIG. 1, a first ply A is sent, via a deflection cylinder 2, from a fixed roller 1 to a working process located in the direction of the arrow P, for example to a packaging machine working continuously. A first optical sensor 3 is disposed approximately at the level of the return cylinder 2.

 Two supports 4 and 5 comprising cutting cutting edges 6 and 7 are arranged below the plane of movement of the ply A. These supports with cutting edge 4 and 5 are mounted, and connected to a drive provided with a control , so as to be able to join, passing from the separated position shown in FIG. 1 to the position of FIG. 4 in which they are in contact with each other by their cutting edges 6 and 7.

 Above the cutting edge supports 4 and 5, there are arranged two counter-supports 4a and 5a which are movable vertically and horizontally and whose horizontal displacement of each is adapted respectively to that of the cutting edge support 4 or 5 associated, so as to move each horizontally and synchronously with the associated cutting edge support. It is also arranged, above the supports with cutting edge 4 and 5, two cutting blades 8 and 9, the cutting edges of which are arranged in the vertical planes of the cutting edges 6 and 7 which are in the position separated from the figure. 1. These cutting blades 8 and 9 are mounted so that they can be moved vertically and are also connected to a drive which is controlled in an exact time manner from the central control unit.

 In the area between the two cutting blades 8 and 9, there is an adhesive strip holder 10 which can be moved vertically and which holds, on its underside, an adhesive strip K which can be released when necessary (see also figure 7). This maintenance can for example be obtained by means of a suction nozzle, by means of a mechanical means or in another way within the reach of the technician. In each case, it should be respected as a condition that the adhesive tape K can be released from its support 10 at the appropriate time.

 Elements 4 to 9 described so far constitute a sectioning device designated as a whole by the reference T.

 Between the cutting device T and the working machine not shown, there is disposed a pair of drive elements 11 and 12 which, when necessary, can be clamped on both sides on the ply A and drive the latter according to the direction of arrow M (Figure 2). By means of a drive provided with a control, at least one of these two drive elements 1 1 and 12 can be moved perpendicular to the ply A and both can be moved in the direction of advance of the tablecloth (arrow P).

 A reserve ply B is placed on a second roller 13, in the standby position. It is also guided by means of a return cylinder 14, passing in front of an optical sensor 5. The end section b of this reserve ply B overlaps the cutting edge 6, itself in the standby position.

 All the elements of the device described so far are connected to a central control unit and are actuated by the latter by means of drive elements, not shown, in such a way as the work described above. after can take place automatically.

 It is first assumed that the sheet A, for example a sheet of plastic material used for packaging purposes, is extracted from the roller 1 and reaches, via the deflection roller 2, at the working machine where it is processed continuously. The reserve ply B located on the roller 13 projects beyond the cutting edge 6 by its end section b overlapping the latter and it is, as has already been indicated, in the standby position.

 As soon as the end of the sheet A supplying the working process passes in front of the optical sensor 3, the latter sends a signal to the central control unit, after which the elements 11 and 12 grasp the sheet and move it forward in the direction of arrow P at a speed which exceeds the speed necessary for feeding the working process to such an extent that the reserve of material R shown in FIG. 2 is formed. The example given, which can be modified by the technician in different respects, shows three return cylinders 16, 17 and 18, the return cylinder 18 can be subjected, in the direction of arrow 19, to the stress of a tension spring not shown, of so that the excess of the material web accumulates between the return cylinders 16, 17 and 18 and is available for the working process.

 As soon as the reserve of ply R necessary for the joining operation has been accumulated, the drive elements 11 and 12 are stopped, in such a way that there also remains on the cutting edge 7 an extreme section straddling the latter. The two end sections a and b are then sectioned, as shown in FIG. 3, by the sectioning blades 8 and 9 moving downwards and they fall, while the two ends of the ply to be joined are clamped on the cutting edge supports 4 and 5 by the counter-supports 4a and 5a also moving downwards, these ends of the sheet thus being immobilized. While this is happening, the working process continues without disturbance, the water reserve R then being gradually consumed.

 The two cutting edge supports 4 and 5 are then brought together (FIG. 4), then, by a downward movement of the adhesive strip holder 10, the adhesive strip K is applied under pressure so to cover the two ends of the tablecloth and thus to bring together the tablecloths (Figure 7). When necessary, the adhesive strip K can be chosen to be thin enough so that, in comparison with an overlapping joint, its thickness is practically not taken into account and that it practically does not interfere with the working process and also remains invisible.

 It is only when the reserve of ply R has been practically completely consumed that the ply is released by raising the drive element 11, 12, the counter-supports 4a and 5a and the adhesive strip holder 10 and that it can then continue to be extracted from the roller 13 by the working machine (FIG. 6). The empty roller 1 is replaced by a new reserve roller 1a, the end of which in turn remains in the standby position, overlapping the cutting edge 6, until the optical sensor 15 announces the presence of the end of the ply B. The end section of the new reserve ply A 'is then located above the ply B during movement.

 The device described can be used for all possible materials in the form of a sheet and capable of being rolled up. The adhesive strip K may for example be a strip of polypropylene with an adhesive underside or a strip of commercial adhesive tape. It is also possible to use a strip of thermoplastic material which is applied by a thermal action applied to melt it.

Claims (6)

 1. Device for automatically joining the final section of a first sheet of material (A), mobile and sent to a working process arranged downstream, with the initial section of a second sheet of material (B) being in position waiting, avoiding an interruption of the working process by forming a reserve of material ply (R) from the final section of the first material ply (A), this device comprising, on the one hand, two supports (4, 5) which support the two layers of material and immobilize them momentarily and which, in a position where the ends of the layers of material are butt-jointed edge to edge, constitute a counter-support for an adhesive strip holder (10) and, on the other hand, a device (8, 9) for cutting the ends of the plies of material which is vertically movable and whose cutting surfaces cooperate with cutting edges (6, 7) produced on the supports (4, 5), the two sections of the na ppes of material being held on these supports and being joined together, in the form of a continuous sheet, by means of an adhesive strip (K) disposed on the adhesive strip holder (10), characterized in that the supports (4, 5) are guided so as to be in a common plane parallel to the plane of movement of the sheets (A, B) and to be able to be moved inside this plane, in one direction and in the other, between a position in which they abut each other by their cutting edges (6, 7) and a position in which they coincide with the cutting surfaces of the cutting device (8, 9) so as to carry out a sectioning, in that the adhesive strip holder (10) is mounted so that it can be moved vertically in translation, with respect to the sheets of material, above the position in which the sectioning edges ( 6, 7) supports (4, 5) are in abutment one on the other, and in that has val supports (4, 5) and upstream of a next processing station in the direction of movement of the first sheet of material (A), there is provided a drive device (11, 12) for the transport of the ply, used to form the reserve (R) from the outgoing end of the first ply (A), the presence of the end of the latter being detected by a sensor (3) disposed upstream of the supports according to the direction of movement and being pulled so as to form the reserve (R) at an increased forward speed after reception of the signal from this sensor by the drive device (11, 12).  2. Device according to claim 1, characterized in that above the supports (4, 5), there are arranged two counter-supports (4a, 5a) which are driven so as to be able to be moved vertically and horizontally and whose the horizontal feed movements are synchronized with the movements of the supports (4, 5).  3. Device according to any one of claims 1 and 2, characterized in that the drive arrangement, used for transporting the sheet, comprises a pair of jaws (11, 12) disposed on either side of the plane for moving the first ply (A) and movable horizontally, the lower jaw (11) serving as a fixed abutment for the upper jaw (12) which is produced so that it can be moved vertically.  4. Device according to claim 1 or 2, characterized in that the drive arrangement, used for transporting the sheet, is produced in the form of a pair of driven cylinders which is provided on either side of the plane displacement of the tablecloth.  5. Device according to any one of claims 1 to 4, characterized in that, to constitute the reserve of material ply (R), there is provided a return arrangement to cylinders (16 to 19) which is subjected to a elastic prestress.  6. Device according to any one of claims 1 to 5, characterized in that the sensors (3, 15) are photoelectric cells.