ITVR20120130A1 - EQUIPMENT FOR SORTING AND STORAGE OF PRINTING SLABS - Google Patents

Description

EQUIPMENT FOR SORTING AND STORING PRINTING PLATES

DESCRIPTION

The present invention relates to an apparatus for sorting and depositing printing plates, intended in particular to be used in printers for printing newspapers and the like.

As is known, in fact, printing plates are plates which are applied from time to time to the cylinders of the rotary presses and which carry the image to be printed on. In particular, each printing plate bears the image relating to one of the basic colors; the overlap of the various basic colors then determines the final image on the sheet of paper. As a result, for example, four printing plates are required to print each four-color page, one for each base color.

More specifically, reference will be made hereinafter to the printing plates used in flexography, even if all the evaluations are to be understood as applicable to printing plates for any technology. The printing plates for flexography consist of a metal support, on which a layer of photopolymer material is applied; the latter during the process of preparation for printing is first polymerized in correspondence with everything that needs to be printed, and subsequently processed in such a way as to remove all uncured material. The final result is that of a layer in which everything that needs to be printed on the paper is embossed.

In general, however, the printing plates are flexible (in that they are of reduced thickness) of rectangular shape and have two opposite edges folded into a V; the latter, with respect to the plate lying flat, therefore define two undercut seats that allow them to be hooked to the cylinders of the rotary presses. On one of the folded edges, then, are reported the data relating to the page imprinted on the plate itself, which then allows its correct positioning on the rotary presses; these data are normally codes that can indicate, for example, the name of the header, the page number, the base color, etc ...

During the printing phase, then, each plate has its specific location on one of the cylinders of the press; each cylinder normally houses eight plates. For each edition, therefore, a different plate is required for each position of each cylinder.

The mounting of the plates on each cylinder is usually done manually. Furthermore, between the plant for preparing the individual plates and the cylinders, the handling of the plates can take place completely manually or automatically.

In the first case (manual handling), each prepared plate is picked up by an operator who identifies it on the basis of the codes shown for example on the folded edge, and assigns it the correct position on the printing cylinders based on correspondence tables; this position is normally marked on the plate by means of an indelible inscription manually affixed by the operator on the polymeric material in correspondence with an area without any raised elements.

Subsequently, the slabs must be divided by the operator according to their final destination (for example slabs for cylinder number 1, slabs for cylinder number 2, etc ...) and subsequently picked up by the operator assigned to the assembly.

In the second case (automatic handling), the plant picks up the plates directly from the preparation unit, which also applies a bar code (generally of the two-dimensional QR type) to the plates, and sends them to the sorting area and storage area. In the sorting and storage area, there is normally provided a stacking apparatus for the plates which comprises handling means which advance the plates arranged flat along a movement path, on the two sides of which two plurality of stacking housings are generally arranged. two by two opposite each other, facing and inclined so as to converge from above towards the central handling means.

In correspondence with each pair of housings there are overturning means capable of overturning a sheet from the handling means to one of the housings. Normally it is envisaged that each housing can house up to thirty-two slabs (a quantity which, in the jargon of the sector, is normally referred to as a "group"). When necessary, then, an operator picks up the pack of plates and divides them to mount them on the various cylinders.

It is also envisaged that the equipment may include two overlapping movement paths, each flanked by the relative housings, in order to reduce the overall length.

However, this known technology has some drawbacks.

In the first place, known stacking apparatuses are complex and expensive, especially since they must have a plate overturning device for each housing.

They also have considerable dimensions, at least for the main printers where many headings are printed every night and hundreds of printing plates are therefore prepared.

Both of these reasons make it necessary to provide that at least thirty-two plates are stacked in each housing so as to reduce both the number of overturning devices required and the overall size.

However, this negatively affects the work of the operators assigned to mounting plates on the presses. In fact, a group of thirty-two plates has a considerable weight which makes the work physically demanding. This is all the more so considering that in order to pick up the stack of plates, the operator must act from the rear of the housing (which faces the handling means) and lift the plates completely above the housing, that is to say practically at least at the height of your head.

A second drawback of known apparatuses is that the plates of each group are intended to be mounted on four different cylinders; the operator must then check each slab and see on which of the four cylinders it should be installed with a considerable increase in terms of assembly times and therefore productivity.

A further drawback of the known processes, regardless of whether or not an apparatus for automatic stacking is used, is that the identification of the individual plates downstream of the preparation station, as well as the affixing of instructions on them installation, are delegated to the skill and concentration of an operator. As a result, errors can occur which, at best, lengthen the mounting times of the plates, and at worst result in the printing of a certain number of incorrect copies.

In this context, the technical task underlying the present invention is to provide an apparatus for sorting and depositing printing plates which remedies the aforementioned drawbacks.

It is a particular technical task of the present invention to provide an apparatus for sorting and depositing printing plates which is more performing, less expensive and which allows a reduction in overall dimensions with respect to known apparatuses.

A further technical task of the present invention is to provide an apparatus for sorting and depositing printing plates which makes the subsequent work by the assembly operators physically easier and less wearing, as well as which reduces the labor required for operation.

A further technical task of the present invention is to provide an apparatus for sorting and depositing printing plates which, with the same overall size, allows the plates to be divided into stacks which include a lower number of plates than those formed by known equipment (advantageously stacks of sixteen or eight plates).

Regardless of this, it is a second technical task of the present invention to provide an apparatus for sorting and depositing printing plates that allows the plates to be divided correctly even in the absence of a bar code printed on them by the printing plant. preparation of the plates. For some types of plates, such as those for flexography in particular, it is not possible to reliably print recognition barcodes on individual plates.

Finally, a third independent technical task of the present invention is to provide a device that allows to avoid errors in reporting on the plate the indication of its subsequent positioning on the printing cylinders.

The technical task and the aims indicated are substantially achieved by an apparatus for sorting and depositing printing plates in accordance with what is described in the attached claims.

Further characteristics and advantages of the present invention will become more evident from the detailed description of a preferred, but not exclusive, embodiment of an apparatus for sorting and depositing printing plates illustrated in the accompanying drawings, in which:

Figure 1 shows a schematic axonometric view of an apparatus for sorting and depositing printing plates according to the present invention;

- Figure 2 shows the apparatus of Figure 1 in a different schematic axonometric view;

- figures 3 and 4 show respectively the details III and IV of figure 2; - figure 5 shows in an axonometric view a part of the equipment of figure 1;

- figure 6 shows an enlargement of a detail of figure 5;

- figure 7 shows an axonometric view of a further part of the equipment of figures 1 and 2;

Figure 8 shows an enlarged view of the detail VIII of Figure 7;

figure 9 shows the part of figure 7 in a disconnected condition; - figure 10 is an enlarged view of detail X of figure 9;

- figure 11 shows a side view of a movable member of the apparatus of figure 1, which includes the part of figure 7;

- figure 12 shows the detail XII of figure 11 enlarged;

- figure 13 shows in a schematic side view, a withdrawal station of the equipment of figures 1 and 2, in a first operational phase;

- Figures 14 to 18, 20 and 21 show a sequence of operating steps subsequent to that of Figure 13, provided for the removal of a plate by a mobile member equipped with gripping means;

- figure 19 shows the detail XIX of figure 18 enlarged;

- Figures 22 to 26, 28 to 30 and 32 show a schematic side view partially in transparency and with some parts removed, a sequence of operating steps foreseen for the deposit of a plate in a housing by the movable member equipped grasping means for the apparatus of Figures 1 and 2;

- figures 27 and 31 show enlarged respectively the details XXVII of figure 26 and XXXI of figure 30;

- Figures 33 to 40 show a sequence of steps for the recognition of a printing plate in the equipment of Figures 1 and 2; in particular, figures 33-35, 38 and 39 show a partially sectioned schematic side view of a recognition station, while figures 36, 37 and 40 show the same recognition station seen from the left with respect to what is illustrated in figure 33;

- Figure 40 shows the equipment of Figures 1 and 2 in front view, with some parts removed to better highlight others, and in a working configuration; And

- figure 42 shows detail XLII of figure 41.

With reference to the aforementioned figures, the reference number 1 globally indicates an apparatus for sorting and depositing printing plates 2 according to the present invention.

As anticipated, the present invention is characterized by the fact that it comprises three inventive aspects that can be applied both in all three in a single device 1, and each independently from the others. Each of them could therefore form the subject of an autonomous patent protection. They will be described in the following substantially in sequence.

As regards the first inventive aspect, as can be seen in Figures 1 and 2, the apparatus 1 for sorting printing plates 2 object of the present invention first of all comprises a support structure 3 which in the illustrated embodiment consists of a first frame 4 and a second frame 5.

On the support structure 3, and more precisely on the first frame 4 in the accompanying figures, at least one pick-up station 6 is identified in correspondence with which support means 7 are mounted for the plates 2, which have the function of supporting a plate to be print 2. In the preferred and illustrated embodiment, the support means 7 allow to support a plate 2 which is arranged at least mainly horizontally as visible in particular in Figure 1 (in Figures 16 and 17 described below). In other embodiments, however, it can also be provided that the support means 7 allow to support the slab 2 arranged vertically or inclined.

In the illustrated embodiment, then, on the first frame 4 there are provided two collection stations 6 side by side, as well as a recognition station 8 (to which we will return hereinafter in relation to the second and third inventive aspects) and the feeding means 9 of the slabs 2 to the pick-up stations 6.

Again on the support structure 3, and in the embodiment illustrated more precisely on the second frame 5, there is then arranged at least a plurality of mainly vertical housings 10, each designed to house a plurality of printing plates 2 arranged mainly vertically. In the illustrated embodiment, however, two pluralities of housings 10 are provided side by side along a main longitudinal direction of the apparatus 1 starting from the two pick-up stations 6. The housings 10 of each plurality are arranged in succession along a path which extends starting from the relative pick-up station 6 and which in the accompanying figures is advantageously rectilinear. Figure 5 shows the first thirty-two housings 10 of each plurality of Figure 1, observed substantially from the opposite side with respect to the observation point of Figure 1 (correspondingly in Figure 5 only the first two thirds of the base portion of the first frame 4 are visible ).

Each housing 10 is then open at the top to allow the insertion into it, from above, of printing plates 2 which are arranged at least mainly vertically (for example as better described below with reference to Figure 28). Preferably, then, the housings 10 present at the top an access opening 11 which has a main extension dimension substantially perpendicular to the path, and a secondary extension direction parallel to the path; advantageously, the size of the access openings 11 along the main development direction is greater than the width of the printing plates 2 (where the width of the plate 2 is generally one of its main dimensions, preferably that which corresponds to the edge provided with the V-shaped folding 12 ), to allow the insertion of the same in the housings 10 keeping them arranged in a substantially vertical plane perpendicular to the path. However, we will return to this point in the following.

The housings 10 of each plurality are therefore side by side with each other with their main directions of development parallel to each other.

In the preferred embodiment, then, as clearly visible in Figure 6, the apparatus 1, in correspondence with each housing 10, comprises an inclined back 13 extending mainly vertically, and a lower support element 14 extending transversely to the back 13 and connected to a lower portion of the back 13 itself. In this way, in use, one or more slabs 2 can be stacked on the back 13. Figure 6 shows only one of these slabs 2. The backs of each housing 10 are also positioned on the side facing the pick-up station 6.

Preferably, then, the support element 14 and the back 13 of each housing 10 are jointly slidingly mounted on the support structure 3 and are movable between an operative position in which they are positioned side by side with those of the housings 10 adjacent thereto (Figures 1 and 2), and a non-operative position in which they are facing away from the adjacent housings 10 and allow free front access to an operator who in use can remove the plates 2 positioned on them (Figures 5 and 6). In particular, as clearly visible in Figure 6, in the preferred embodiment each back 13 and the relative support element 14 are configured as extractable drawers 15 equipped with an external side 16 equipped with a handle 17 for gripping and handling, and with a side internal 18. When the drawer 15 is extracted as in figure 6, it is possible to freely access the relative back 13 from the front and remove any slabs 2 stacked on it. For this purpose, the back 13 advantageously has two grip openings 19 arranged at an intermediate height and on the two sides thereof, in such a way as to be, in use, straddling the lateral edge of the stacked slabs 2; in this way the operator can insert each hand from the front into a gripping opening 19, access the opposite face of the slabs 2 and easily withdraw them. The upper band 20 of each back 13 (above the position in which the upper edge of a slab 2 inserted in the housing 10 is found) is finally inclined in the opposite direction with respect to the rest of the back 13 to facilitate insertion. of the plates 2 in the rear housing 10 as explained below.

The sliding movement of each drawer 15 can be ensured by suitable guides 21 of the type commonly used for moving drawers 15 and the like; they will therefore not be described further.

Advantageously, moreover, each drawer 15 is made in such a way that the support element 14 is vertically misaligned with respect to the corresponding access opening 11, on the vertical of which the back 13 is instead present; as explained below, this facilitates the insertion of the plates 2 into the housing 10.

Returning to figures 1 and 2, in accordance with the present invention, for each plurality of housings 10 provided, the apparatus 1 then comprises at least one mobile member 22 which can be moved along the path and is equipped with gripping means 23.

The gripping means 23 have the purpose of hooking a printing plate 2 at its edge when it is on the support means 7 in the pick-up station 6, and of releasing it when it is inserted in a relative housing 10.

Furthermore, the movable member 22 allows the movement of the gripping means 23 between a lowered position in which they can at least release a plate 2 in a housing 10, and a raised position in which they can hold a plate 2 arranged substantially vertically above the Housing 10. Preferably, moreover, in its lowered position, the gripping means 23 can also interact with a printing plate 2 placed in the pick-up station 6 to hook it. However, it can also be provided that the gripping means 23 can hook a slab 2 when they are in the raised position (for example if in the pick-up station 6 the slab 2 is arranged vertically), as well as that they can assume different lowered positions, at heights different, one for depositing the plates 2 in the housings 10 and one for removing the plates 2.

Advantageously, in the preferred embodiment, the gripping means 23 comprise at least one rod 24 arranged substantially horizontally and which has an upper side 25 which can be hooked to a substantially V-shaped folding 12 of an edge of each printing plate 2; as said with reference to the known art, in fact, each printing plate 2 normally has two opposite edges folded into a V which have the purpose of allowing it to be mounted on the printing cylinders. Advantageously, as can be seen in figure 19 where the rod 24 is shown coupled to the edge provided with the V-shaped folding 12, the upper side 25 of the rod 24, in order to be hooked, is partially counter-shaped to the V-shaped folding 12 itself, and has especially a bevel.

In accordance with the present invention, then, when the movable member 22 is in correspondence with the pick-up station 6 and the gripping means 23 in the relative lowered position, the rod 24 is located at a lower (vertical) height with respect to that which can be assumed by a printing plate 2 which is arranged on the support means 7 in the pick-up station 6 itself. In this way, in fact, as better explained in the following, the subsequent passage of the rod 24 from the lowered position to the raised position first determines, in use, the same contact with a plate 2 arranged in correspondence with a pick-up position identified on the pick-up station 6, and subsequently the hooking to the edge equipped with the 12 V-folding.

In order to allow the plate 2 to be moved along the path when it is hooked by the gripping means 23, it is advantageously provided that with the gripping means 23 in a raised position, along the entire path of the movable member 22 the rod 24 is spaced from each housing 10 by a distance greater than the length of a printing plate 2.

As can be seen in figures 1 and 2, then, in the preferred embodiment to define the movement path of the movable member 22, the support structure 3 comprises at least one crosspiece 26 substantially parallel to the path. In turn, the movable member 22 comprises a hooking body 27 slidably mounted along the crosspiece 26; the sliding of the body along the crosspiece 26 determines the displacement of the movable member 22 along the path. As can be seen in Figures 3, 4, 12 and 42, in the illustrated embodiment the coupling body 27 comprises a first trolley 28 to which four first wheels 29 coplanar in a vertical plane are rotatably coupled, two above and two below being associated with a first track defined by the crosspiece 26. A first motor 30 is then connected to a first omega transmission 65 (shown only in Figure 42) which is engaged with a fixed toothed belt which extends parallel to the movement path; the first motor 30 then controls the rotation of the first omega transmission 65 to determine a controlled movement of the hooking body 27 along the crosspiece 26.

It should however be noted that in other embodiments other systems for moving the coupling body 27 along the crosspiece 26 can also be adopted. By way of example, the first wheels 29 can be toothed wheels and be coupled either with racks or with toothed belts integral with the crosspiece 26 .

A substantially vertical upright 31 is then slidingly coupled to the hooking body 27 which carries the gripping means 23 at the bottom. The upright 31 is movable with respect to the hooking body 27 at least between an upper position in correspondence with which the gripping means 23 are in its raised position and a lower position in correspondence with which the gripping means 23 are in its lowered position (Figure 11).

More in detail, in the illustrated embodiment, a second trolley 32 is fixed to the hooking body 27 equipped with four second wheels 33 coplanar in a vertical plane. Unlike the first trolley 28 which slides along the crosspiece 26, however, as regards the second trolley 32 it is the upright 31 that slides with respect to it; the four second wheels 33 are in fact coupled two to one vertical side, two to the other, of the upright 31. Also in this case a second motor 34 is connected to a second omega transmission (not visible in the accompanying figures), meshed with a toothed belt (not shown) integral with the upright 31, to control its rotation and determine the vertical translation of the mounted with respect to the coupling body 27.

It should be noted that, as illustrated in Figures 41 and 42, in the illustrated embodiment the upright 31 can translate upwards with respect to the coupling body 27 up to an extreme position higher than that in which the gripping means 23 are in raised position; in this embodiment, in fact, two movable members 22 are provided for each path, the coupling bodies 27 of which are coupled to opposite sides of the crosspiece 26. The presence of two movable members 22 has the function of increasing the productivity of the apparatus 1 : while one of the two movable members 22 is returning unloaded towards the collection station 6 (the highest one in figure 42), the other (the lowest one in figure 41) can move from the collection station 6 towards one of the housings 10 to carry a plate 2. The fact of providing for the possibility of bringing the upright 31 to the extreme position during the return to the pick-up station 6 allows the relative rod 24 to cross the rod 24 of the other movable member 22 located at the relative raised position coupled to a plate 2, without impacting either against it or against the plate 2 carried by it (Figure 42). This expedient is not needed in the case in which a single movable member 22 is provided per path.

As can be seen in particular in Figures 7, 8 (which do not show the coupling body 27) and 11, advantageously the upright 31 in turn has a first part 35 connected to the coupling body 27, and a second part 36 to which it is coupled the rod 24, and which is slidingly connected to a lower area of the first part 35. In the accompanying figures this is obtained by fixing a V-shaped guide 37 to the first part 35 and by sliding the second part 36 (the two are counter-shaped to each other). A head 38 fixed at the top of the second part 36 prevents it from sliding downwards (Figure 11). On the contrary, nothing prevents the possible slipping of the second part 36 from the first part 35 following its upward movement; consequently, the upward sliding of the second part 36 with respect to the first part 35 beyond a predetermined stroke determines its decoupling. In this way, if during operation, in the passage of the gripping means 23 from the raised position to the lowered position, something blocks the relative rod 24, the first part 35 of the upright 31 would continue to descend while the second part 36 with the rod 24 they would decouple. This sliding connection between the two parts 35, 36 can also be useful during maintenance to quickly replace a possibly defective or damaged rod 24 with a new one.

As can be seen in figures 8 to 10, then, advantageously the rod 24 has a first end 39 connected to a lower end of the upright 31 (and in particular in the attached figures of its second part 36) by means of hooking means 40 suitable for allowing it decoupling if an external stress greater than a threshold value acts between the two. The coupling means 40 comprise a plurality of balls 41 interposed between the rod 24 and the upright 31. Each ball 41 is partially inserted in two opposing seats 42 in the shape of a spherical segment, one made in the rod 24 and one in the upright 31 (visible in figure 31 where the spheres have been removed for clarity). An elastic element 43 acts on rod 24 and upright 31 to clamp the balls 41 between them and allows the decoupling between rod 24 and upright 31 when the external stress above the threshold value acts between the two (Figure 10). Even more in detail, in the illustrated embodiment the rod 24 is connected to the upright 31 in correspondence with one of its terminal recesses 44 and the elastic element 43 comprises two leaf springs 45, 46 a V-shaped 45 fixed to close the recess terminal 44 and a mainly flat one 46 fixed on the other side of the recess 44. As shown in Figure 10, in the moment of possible decoupling the two leaf springs 45, 46 deform outwards.

Advantageously, then, the apparatus 1 comprises a control unit operatively connected to all the active parts / devices of the apparatus 1 such as the mobile member 22 (i.e. to the first motor 30 and to the second motor 34 in the illustrated embodiment) and the others / others described below.

Figures 13 to 21 show the sequence of steps provided for the removal of a slab 2 by the movable member 22 starting from the withdrawal station 6.

In the illustrated embodiment, the support means 7 are constituted by a plurality of bars 47 (only one of the bars 47 is therefore visible in figures 3-21, where it is highlighted in hatching) arranged parallel to the path and at a certain distance one from the 'other. The bars 47 can also be moved vertically between a working position and a rest position.

The bars 47 are interspersed with drive belts 48, which are also parallel to the path and each wrapped around at least two pulleys 49 at least one of which is motorized and controlled by the control unit. When the bars 47 are in the working position, they are placed at a higher level than the belts 48 while, when they are in the rest position, they are placed at a lower level. In the first case, any printing plates 2 rest on the bars 47, in the second on the belts 48. In other embodiments, however, the supporting means 7 can also consist of only the belts 48 or other elements.

Although the belts 48 represent the preferred embodiment of means for horizontal translation of the printing plate 2 at the pick-up station 6, other solutions can be adopted according to requirements.

Also in correspondence with the pick-up station 6 there are also a first sensor 50 for detecting the presence of a plate 2 aligned with it, a second sensor 51 for detecting the presence of a plate 2 aligned with it, a third sensor 52 for detecting the rod 24 placed in its lowered position, and a magnetic element 53 (consisting of a permanent magnet or an electromagnet). All the sensors 50, 51, 52 can be either of the electromagnetic or optical type.

The control unit is also operationally connected to the translation means and to the sensors 50, 51, 52, to control the operation of the translation means in a coordinated manner with the movable member 22.

Advantageously, in the embodiment illustrated, to allow the removal of a slab 2, the control unit is programmed to perform the following steps in use:

activating the translation means to bring a printing plate 2 to a waiting position in which the edge provided with the V-shaped folding 12 is located at a first distance from a pick-up position; in the accompanying figures, the positioning of the plate 2 in the waiting position is signaled to the control unit by the first sensor 50 (Figure 13); bring the mobile member 22 in correspondence with the pick-up station 6 by acting on the first motor 30 (again figure 13 where the gripping means 23 are shown arranged just above its lowered position);

with the printing plate 2 kept in the waiting position, bring the gripping means 23 to the lowered position (Figure 14); in the illustrated embodiment, reaching the position is signaled by the third sensor 52; at that point the rod 24 is located at a lower level than the plane of the printing plate 2 identified by the translation means;

with the gripping means 23 in a lowered position, activate the translation means to move the edge with the V-shaped folding 12 up to the pick-up position, in correspondence with which the printing plate 2 is above the gripping means 23 ( figure 15); the reaching of the withdrawal position is signaled by the second sensor 51.

bringing the gripping means 23 into the raised position; during the transition from the lowered to the raised position, the rod 24 hooking into the V-shaped folding 12 and the printing plate 2 being lifted by the gripping means 23 (Figure 21).

The various phases of coupling and lifting are illustrated in more detail in figures 16 to 21.

In the first place, advantageously, before starting the lifting of the rod 24, the bars 47 are brought into the working position so that the plate 2 rests exclusively on the support means 7 (Figure 16); in fact, the support means 7 can be made of steel and can ensure a better sliding of the plate 2 during hooking, as will become more evident from the following description.

At that point the rod 24 is raised until it comes into contact with the plate 2 (figure 17) and continuing the lifting, its upper side 25 first slides against the lower face of the plate 2 causing it to bend, then it is inserted into the folding 12 a V of the edge by hooking the plate 2 (figure 18) and then lifting it (figure 19).

Since during the lifting, as illustrated in figure 18, the plate 2 undergoes an elastic bending, when the rear edge of the plate 2 detaches itself from the support means 7, the plate 2 itself tends to oscillate. At that point, two possibilities are advantageously provided. If the slab 2 is intended to be placed in a housing 10 sufficiently far from the withdrawal station 6, it is not necessary to do anything as the oscillation tends to vanish in the time necessary to reach the housing 10; the rod 24 can therefore be brought directly to the raised position (Figure 21). If, on the other hand, the housing 10 is closer and it is therefore not possible for the oscillation to dampen sufficiently before reaching it, it is advantageously provided that the rod 24 is stopped a little before the raised position, so that the edge bottom of the plate 2 arranged vertically comes into contact with the magnetic element 53 which locks it in the vertical position, eliminating the oscillation (Figure 20); after a short wait (of the order of a few tenths of a second) the rod 24 can be brought into the raised position (figure 21). As illustrated in Figure 20, moreover, as soon as the plate 2 is detached from the support means 7, a new movement of the bars 47 towards the rest position begins.

Figures 22 to 32 instead show how a plate 2 hooked to the rod 24 is subsequently deposited in a housing 10. In particular, this is illustrated with reference to the thirteenth housing 10 (all by observing the apparatus 1 from the same side of figure 2); consequently, only some of the housings 10 are shown in the figures, the most significant each time (in figures 22 to 25 the first thirteen housings 10, in the others only the one where the insertion is taking place and the one immediately in front of it).

Firstly, when the rod 24 is in the raised position at the pick-up station 6, the movable member 22 is moved towards the housing 10 where the plate 2 must be deposited. During the displacement, as illustrated in Figure 22, the plate 2 can undergo further oscillations.

Once the plate 2 has arrived at the correct housing 10, the movable member 22 is stopped. Advantageously, however, the stop occurs with a gradual braking (figure 23) which allows to minimize any residual oscillations of the plate 2 (figure 24). Furthermore, the stop can preferably always take place in a relatively advanced position that is suitable for the insertion of the plate 2 regardless of whether it is the first or the last plate 2 of the stack.

Alternatively, for the same housing 10 the stopping position of the plate 2 can vary according to the number of plates 2 already present therein; the greater the number of plates 2 present, the more the plate 2 will be stopped near the next housing 10 along the path (the one in front of the one of interest). In this case, however, a monitoring system is required for the number of plates 2 present in each housing 10. When the plate 2 has reached its position, or already during braking, the movable member 22 moves the rod 24 towards the lowered position as illustrated in figure 28; the same figure shows how at a certain point, during the descent, the lower edge of the slab 2 comes into contact with the back 13 (or with the inner face of the upper slab 2 of any previously formed pile); continuing the descent the slab 2 flexes and its lower edge follows the trend of the back 13 until it touches the support element 14 (or the lower edge of the upper slab 2 of the stack) as shown in figure 29.

At that point, as shown in Figures 30 and 31, the further descent of the rod 24, advantageously up to the lowered position, causes the release of the plate 2. At that point the elasticity of the plate 2 causes it to stretch on the back 13 or on the stack of other plates 2 already present (figure 32). Note that with the described deposit procedure, the pile is formed with the lower edges of the slabs 2 inserted one inside the other, while the upper ones are placed on top of each other; consequently, the thickness of the stack will be lower at the bottom than at the top.

Figures 25 to 27 instead show what happens if at the time of inserting the plate 2 in its housing 10, the plate 2 is still subject to a certain oscillation or if, by choice, the plate 2 is stopped in a very advanced position. In both cases, its lower edge hits the rear side of the upper band 20 of the back 13 (the one inclined in the opposite direction to the rest of the back 13) of the drawer 15 in front of the one of interest, which therefore acts as a guide and bounces it into the correct slot 10.

In the preferred embodiment, it is then provided that the positioning of the plates 2 in the various housings 10 is not random, but is linked to the final destination of the plate 2; in particular, it can be provided that in each housing 10 either only the plates 2 intended to be mounted on a single cylinder (eight plates 2) or only those intended for two superimposed cylinders of a rotary press (sixteen plates 2) can be inserted. In this way, in fact, the operator who picks them up can go directly to the right place and proceed with assembly. To do this, however, the control unit must know at all times that plate 2 is in every position. This information can be communicated to it both during the loading of the plates 2 onto the apparatus 1 and from any equipment placed upstream in the plant for preparing the plates 2. Alternatively, as better described below, the apparatus 1 can be equipped of a plate recognition system 2 made in accordance with the second inventive aspect of the present invention.

While in general the apparatus 1 according to the present invention can comprise both a plurality of pick-up stations 6, and a plurality of paths along each of which at least one movable member 22 is movable, and a plurality of movable members 22 along each path, in the embodiment of figures 1 and 2 there are provided, as mentioned, two paths side by side, each of which starts from a relative pick-up station 6, and two movable members 22 for each path.

The feeding means 9 which feed the plates 2 to these pick-up stations 6 comprise a roller path 54 which extends along a direction perpendicular to that of the paths, and two belt paths, similar to that described with reference to the pick-up station 6, which cross the roller way 54 in correspondence respectively with an intermediate portion thereof and a final portion thereof. At the intersections, the belts can be raised or lowered to take the sheets 2 in load or respectively leave them in load on the roller way 54. The sheets 2 can then be fed to the initial portion of the roller way 54 in any way suitable for the scope.

Furthermore, as anticipated, in the embodiment illustrated in correspondence with the initial portion of the roller path 54 the apparatus 1 comprises a station 8 for recognizing the printing plates 2.

However, it should be noted that everything concerning the recognition station 8 forms part of the second inventive aspect of the present invention, and can therefore be completely disconnected from what has been described up to now; consequently, what will now be described with reference to the recognition of the plates 2 can also find application in any other sorting and / or stacking apparatus 1 which is equipped with a control unit capable of using this information to follow the subsequent movement of the plate 2 and selectively accumulate it in a predetermined pile. Therefore, an independent object of the present invention also forms a generic apparatus 1 for stacking and / or sorting printing plates 2 which is equipped with a plate recognition system 2 of the type described below.

The description of the recognition system will be made with reference to Figures 33 to 40 in which the plates 2 are fed to the recognition station 8 in a direction perpendicular to the direction of movement identified by the roller path 54; in any case, different power supplies can be provided in other embodiments.

Figures 33-35, 38 and 39 show the recognition station 8 according to a side view observed according to the direction of movement of the roller path 54; one of the rollers 55 highlighted by hatching is therefore visible laterally.

Otherwise, figures 36, 37 and 40 show the same recognition station 8 according to an observation direction parallel to the rotation axis of the rollers 55.

The 8 plate recognition station 2 comprises at least one camera 56 (five side by side in the accompanying figures) and an image processing unit (not shown and advantageously coincident also with the control unit if present, since both can consist of a single computer) connected to the camera 56 to receive from it at least an image of the printing plate 2 which represents an area thereof in which the recognition codes of the plate 2 itself are reported. The camera 56 is in fact arranged to film, in use, an area of the printing plate 2 which is equipped with identification codes. In the preferred embodiment (referring for example to flexographic printing), this is the area corresponding to the edge with the V-fold 12 where a series of alphanumeric characters is shown.

The image processing unit is then programmed to recognize the recognition elements present on the printing plate 2 and detected in the image, and to establish a correspondence between the recognized elements and the destination of the plate 2 based on previously stored information.

The result of this processing can be used both in the context of the second inventive aspect of the present invention to allow a controlled positioning of the plate 2 in a specific housing 10, and in the context of the third inventive aspect of the present invention.

In accordance with the third inventive aspect of the present invention, in fact, the recognition means further comprise at least one printer 57 positioned above the roller path 54 to print information on a plate 2 which has been recognized by the recognition means. This concerns in particular the information relating to the subsequent positioning of the plate 2 in the rotary presses. The control of the printer 57 can also be entrusted to the image recognition unit which, once the identity of the plate 2 has been established, can retrieve information about its positioning from previously stored data, and have this information printed in correspondence with an area of the plate. 2 intended not to be used for subsequent printing in presses.

In the illustrated embodiment, then, the recognition station 8 also comprises lighting means 58 of the area to be detected such as a strip of LEDs, abutment elements to ensure an almost perfect positioning of the plate 2 to be detected, as well as a plurality of conveyors belt conveyors 59 interspersed with the rollers 55 of the roller way 54 55. The belt conveyors 59 can also be raised and lowered in this case to selectively rest the plates 2 on themselves or on the rollers 55 (in figures 36, 37 and 40 the belts of belt conveyors 59 are not shown).

The sequence of operation of the recognition station 8 is illustrated in Figures 33 to 40.

Figure 33 shows a plate 2 advancing on the belt conveyors 59 which are raised with respect to the roller way 54 55. In figure 34 the plate 2 has reached the position and is resting against a first abutment element 60. A fourth sensor 61 (of the type described above) detects its correct positioning when the plate 2 has completely passed it.

Subsequently, the belt conveyors 59 are lowered and the plate 2 rests only on the rollers 55 (Figures 35 and 36).

At that point, the rollers 55 are activated in the opposite direction with respect to when they have to feed a plate 2, and bring it into contact with a second abutment element 62 (Figure 37). Also in this case a fifth sensor 63 checks its correct positioning.

Since the plate 2 is now positioned in a precise manner along the two possible directions of movement, it is possible to detect the image; then both the lighting means 58 and the camera 56 are activated, but advantageously only after the belt conveyors 59 have been raised again (Figure 38). It should be noted that in other embodiments both the lighting means 58 and the camera 56 can be kept always active.

Once the detection has been carried out, the belt conveyors 59 are activated to move the plate 2 back until it comes into contact with a third abutment element 64 which in the meantime has been made to protrude upwards with respect to the belt conveyors 59 themselves (Figure 39). Also in this case the correct positioning of the plate is signaled by the fourth sensor 61.

Finally, the belt conveyors 59 are lowered and the sheet 2 is picked up by the rollers 55 which make it advance towards the pick-up stations 6; during the exit from the recognition station 8, the printer 57 imprints on the plate 2 the information tracked in the meantime by the image processing unit (Figure 40).

Subsequently, the advancement of the plate 2 is controlled by the control unit which is therefore able to know when that plate 2 will be taken over by the gripping means 23 and will be able to command its insertion in the relative housing 10.

The present invention achieves important advantages.

In the first place, the apparatus for sorting and depositing printing plates object of the first inventive aspect of the present invention is less expensive than known apparatuses, since it requires a considerably lower number of devices for stacking the plates (generally one or two for tens of housings) with respect to known apparatuses (which provide one for each housing).

Being then based on stacking from above in almost vertical stacks, the equipment allows a significant reduction in overall dimensions and / or to have a greater number of housings with an overall size not exceeding the known equipment. Consequently, it is possible to stack a smaller number of plates (in particular eight or sixteen) in each housing, which makes subsequent manipulation by the operator much easier.

The particular extractable drawer conformation of the housings also contributes favorably to making the subsequent work by the assembly operators physically easier and less wearing. Moreover, thanks to the equipment object of the present invention, the necessary manpower is also reduced.

The second inventive aspect of the present invention (that relating to recognition) then makes it possible to divide the plates into the stacks according to their final destination on the printing cylinders even in the absence of an identification bar code shown on the individual plates, and this independently of the whether the apparatus is otherwise made in accordance with the first characterizing aspect of the present invention or not.

The third inventive aspect of the present invention, on the other hand, makes it possible to avoid the risk that an operator may make mistakes when assigning a plate to a specific destination in the rotary presses. Finally, it should be noted that the present invention is relatively easy to produce and that the cost associated with its implementation is also not very high.

The invention thus conceived is susceptible of numerous modifications and variations, all falling within the scope of the inventive concept that characterizes it.

All the details can be replaced by other technically equivalent ones and the materials used, as well as the shapes and dimensions of the various components, may be any according to requirements.

Claims (18)

CLAIMS 1. Equipment for sorting and depositing printing plates, characterized by the fact of comprising: a support structure (3); support means (7) mounted on the support structure (3) at a pick-up station (6), to support a printing plate (2); a plurality of housings (10) with mainly vertical development arranged on the support structure (3) in succession along a path which extends from the pick-up station (6) each intended to house a plurality of printing plates (2) arranged mainly vertically, said housings (10) being open at the top to allow the insertion into them from above of printing plates (2) arranged at least mainly vertically; And at least one movable member (22) along said path and equipped with gripping means (23) for hooking a printing plate (2) at one edge thereof when it is on the support means (7) and for releasing it when it it is inserted in a relative housing (10); said member allowing the movement of the gripping means (23) between a lowered position in which they can at least release a printing plate (2) in a housing (10) and a raised position in which they can hold a plate (2) arranged substantially vertically . 2. Apparatus according to claim 1 characterized in that in said lowered position the gripping means (23) can also interact with a printing plate (2) placed in the pick-up station (6) to hook it. 3. Apparatus according to claim 1 or 2 characterized in that the gripping means (23) comprise at least one rod (24) arranged substantially horizontally and having an upper side (25) which can be hooked to a substantially V-shaped folding (12) one edge of each printing plate (2). 4. Apparatus according to claims 2 and 3 characterized in that when the movable member (22) is in correspondence with the pick-up station (6) and the gripping means (23) in said lowered position, the rod (24) is placed at a lower level than that assumed by a printing plate (2) placed in the pick-up station (6), and the passage from the lowered position to the raised position causing in use the contact of the same with a plate (2) arranged in correspondence to a pick-up position identified on the pick-up station (6). 5. Apparatus according to any one of the preceding claims characterized in that the support means (7) allow to support a printing plate (2) arranged at least mainly horizontally, 6. Apparatus according to any one of the preceding claims characterized in that with the gripping means (23) in said raised position, along the entire path of the movable member (22) the rod (24) is spaced from each housing ( 10) a distance greater than the length of a printing plate (2). 7. Apparatus according to any one of the preceding claims characterized by the fact that said housings (10) have an access opening (11) at the top having a main dimension of development substantially perpendicular to the path, and by the fact that they are side by side with each other with the main directions of development parallel to each other. 8. Apparatus according to any one of the preceding claims characterized in that it comprises, in correspondence with each housing (10) an inclined back (13) extending mainly vertically, and a lower support element (14) extending transversely to the back (13) and connected to a lower portion of the back (13), in use one or more plates (2) being able to be arranged substantially parallel to the back (13) and stacked on it. 9. Apparatus according to claim 8 characterized in that the support element (14) and the backrest (13) of each housing (10) are jointly slidingly mounted on the support structure (3) and are movable between an operative position in which are positioned side by side with those of the housings (10) adjacent to them, and a non-operative position in which they are facing away from the adjacent housings (10) and allow free front access for in use remove the plate (2) positioned on them . 10. Apparatus according to any one of the preceding claims characterized in that the support structure (3) comprises at least one crosspiece (26) substantially parallel to the path, and in that the movable member (22) comprises a coupling body (27 ) slidably mounted along said cross member (26), the sliding of the body along the cross member (26) causing the movement of the mobile member (22) along the path, and a substantially vertical upright (31) bearing the gripping means (23 ), slidingly coupled to the coupling body (27) and movable with respect thereto between an upper position in correspondence with which the gripping means (23) are in its raised position and a lower position at which the gripping means (23 ) are in their low position. 11. Apparatus according to claims 3 and 10 characterized in that the rod (24) has a first end (39) connected to a lower end of said upright (31) by means of coupling means (40) which comprise a plurality of balls each partially inserted in a seat obtained in the rod (24) and in a seat obtained in the upright (31), and at least one elastic element (43) which acts on the rod (24) and upright (31) to clamp the balls together , the elastic element (43) allowing the decoupling between the rod (24) and the upright (31) when an external stress greater than a threshold value acts between the two. 12. Apparatus according to claims 3 and 10 or 3 and 11 characterized in that the upright (31) has a first part (35) connected to the coupling body (27), and a second part (36) to which the rod (24), and which is slidingly connected to a lower area of the first part (35), the upward sliding of the second part (36) with respect to the first part (35) beyond a predetermined stroke causing its decoupling. 13. Apparatus according to claims 4, 5 and any of the other preceding claims, characterized in that it further comprises means for horizontal translation of the printing plate (2) located in correspondence with the pick-up station (6), and a control unit operatively connected both to the translation means and to the movable member (22) to control its operation in a coordinated way, and by the fact that the control unit is programmed to perform the following steps in use: activating the translation means to bring a printing plate (2) to a waiting position in which said edge provided with the V-shaped folding (12) is located at a first distance from a pick-up position; bring the mobile part (22) to the pickup station (6); with the printing plate (2) in the waiting position, bring the gripping means (23) to the lowered position, in correspondence with which the rod (24) is at a lower level than the plane of the printing plate ( 2) identified by the means of translation; with the gripping means (23) in this lowered position, activate the translation means to move the edge with the V-shaped folding (12) up to the pick-up position, in correspondence with which the printing plate (2) is located below above the gripping means (23); bring the gripping means (23) into the raised position, during the passage from the lowered to the raised position the rod (24) hooking into the V-shaped folding (12) and the printing plate (2) being raised by the gripping means ( 23). 14. Apparatus according to any one of the preceding claims characterized by the fact of comprising a plurality of sampling stations (6), and / or by the fact of comprising a plurality of paths along each of which at least one movable member (22) and / or by comprising a plurality of movable members along each path. 15. Apparatus according to any one of the preceding claims, characterized in that it further comprises a station for recognizing the printing plates (2) arriving at the pick-up station (6). 16. Apparatus according to claim 15 characterized in that the plate recognition station (8) (2) comprises at least one camera (56) and an image processing unit connected to the camera (56) to receive at least one image of the plate to be printing (2) and programmed to recognize any identification elements present on the printing plate (2) and detected in said image. 17. Apparatus according to claim 16 characterized in that said video camera (56) is arranged to film, in use, a V-folded edge of a printing plate (2) which is equipped with identification codes. 18. Apparatus according to claim 15, 16 or 17 characterized in that it further comprises at least one printer (57) for printing information on a plate (2) recognized by the recognition means.