The present invention relates to a device for unloading and storing preforms for the production of containers made of plastics.

Devices for unloading and storing preforms for the production of containers made of plastics are known which are usually constituted by a cooling plate that defines a plurality of receptacles arranged in a matrix and intended to accommodate respective still-hot preforms for the time required to cool them down at least partially.

Typically, these preforms are fed directly by the injection press to the cooling plate and remain in the respective receptacle for a preset time.

Specifically, once the injection process has ended, the mold opens and the cooling plate is moved toward the preforms partially accommodated in one of the two mold parts so that the receptacles can engage respective portions of preforms that emerge from the mold part in order to extract them therefrom so as to allow the mold to close and allow a new molding cycle.

The unloading of the preforms from the cooling plate occurs following an action of expulsion by pushers arranged at the bottom of the receptacles.

Following expulsion from the cooling plate by the pushers, the preforms by then already at least partially cooled fall by gravity onto a conveyor belt, which then makes them fall, again by gravity, into a container.

The solution described above, despite being widely used, is not however free from drawbacks.

First of all, the preforms, despite having undergone a certain cooling, still have some of their portions, typically the bottom one, that are not perfectly rigid, and accordingly the falls can cause localized deformations.

Moreover, the fall by gravity inside the container causes a random arrangement of the preforms that reduces in practice, the quantity of preforms that can be placed in each container.

The aim of the present invention is to eliminate, or at least reduce drastically, the drawbacks described above.

Within this aim, an object of the invention is to provide a device for unloading and storing preforms for the production of containers made of plastics that allows to unload, in an extremely practical and effective manner, the preforms from the cooling plate into the containers.

Another object of the invention is to provide a device for unloading and storing preforms for the production of containers made of plastics that allows to accommodate, inside the containers, a greater number of preforms.

This aim and these and other objects that will become better apparent hereinafter are achieved by a device for unloading and storing preforms for the production of containers made of plastics according to the provisions of claim 1.

Further characteristics and advantages of the invention will become better apparent from the description of some preferred but not exclusive embodiments of a device for unloading and storing preforms for the production of containers made of plastics according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Figure 1 is a perspective view of a device for unloading and storing preforms for the production of containers made of plastics during the step of picking up the preforms from the cooling plate;

Figure 2 is a front elevation view of the device during the pick-up step;

Figure 3 is a top view of the device during the pick-up step;

Figure 4 is a perspective view of the device during a first intermediate step of transfer of the preforms from the cooling plate toward a container;

Figure 5 is a front elevation view of the device in the first intermediate transfer step; Figure 6 is a top view of the device in the first intermediate transfer step;

Figure 7 is a perspective view of the device during a second intermediate step of transfer of the preforms from the cooling plate toward a container;

Figure 8 is a front elevation view of the device in the second intermediate transfer step;

Figure 9 is a top view of the device in the second intermediate transfer step;

Figure 10 is a perspective view of the device during a step for unloading the preforms into the container;

Figure 11 is a sectional view of the device in the unloading step;

Figure 12 is a top view of the device in the unloading step;

Figure 13 is a perspective view of a constructive variation of the device during the step for pick-up of the preforms from the cooling plate;

Figure 14 is a side elevation view of the device of Figure 13 in the pick-up step;

Figure 15 is a side elevation view, from another point of view, of the device of Figure 13 in the pick-up step;

Figure 16 is a perspective view of the variation of the device during an intermediate step of transfer of the preforms from the cooling plate toward a container;

Figure 17 is a side elevation view of the device of Figure 16 in the intermediate transfer step;

Figure 18 is a side elevation view, from another point of view, of the device of Figure 16 in the intermediate transfer step;

Figure 19 is a perspective view of the variation of the device during a step for unloading the preforms into the container;

Figure 20 is a side elevation view of the device of Figure 19 in the unloading step; Figure 21 is a side elevation view, from another point of view, of the device of Figure 19 in the unloading step;

Figures 22 to 25 are perspective views of constructive variations of the device according to the invention.

The present invention refers to a device, generally designated by the reference numeral 1, for unloading and storing preforms 10 for the production of containers made of plastics.

The unloading and storage device 1 comprises at least one cooling plate 2, which defines a plurality of receptacles 3 for respective preforms 10.

The device 1 is provided with means for transferring the still-hot preforms from an injection molding device, not shown in the figures, to the cooling plate 2.

According to the present invention, the device 1 comprises pick-up means 20, which are adapted to pick up the preforms 10 from the cooling plate 2 and place them inside at least one accommodation container 4.

At the practical level, the pick-up means 20 can comprise a robot selected, for example, among:

- Cartesian robots;

- cylindrical robots;

- spherical robots;

- SCARA robots;

- articulated or anthropomorphic robots.

According to a practical embodiment, the pick-up means 20 comprise at least one Cartesian robot 24 (as shown in Figures 13 to 21).

Advantageously, as shown in Figures 1 to 12, the pick-up means 20 comprise an anthropomorphic robot 21.

Conveniently, the pick-up means 20 comprise a plate 22 that supports a plurality of supporting bodies 23 for a respective preform 10.

Advantageously, the supporting bodies 23 are arranged in a matrix. With reference to the embodiment shown in the figures, the supporting bodies 23 comprise respective protrusions that are extended substantially at right angles to the plate 22.

In order to allow the unloading of the preforms 10, the protrusions are associated with at least one pusher body 24 to unload the preforms from the respective supporting body 23.

This or these pusher bodies 24 is/are movable, on command, substantially at right angles with respect to the direction of extension of the protrusions in order to abut against a portion of the preforms 10 and disengage them from said protrusions so as to allow their placement inside the accommodation container 4.

Conveniently, during the preform unloading step the plate 22 is arranged substantially parallel to the bottom of the accommodation container 4.

According to a particularly important aspect of the invention, the pick-up means 20 are adapted to unload the preforms 10 in an orderly manner into the accommodation container 4.

By way of example, the means for transferring the still-hot preforms from the injection molding device to the cooling plate 2 comprise a device for moving the cooling plate 2 with respect to the molding device in order to pick up directly the still-hot preforms from the molding device in the open condition.

In particular, the injection molding device is constituted by a first mold part and a second mold part which can move with respect to each other between a closure position, in which they cooperate in order to define cavities that correspond to the shape of the preform 10, and an opening position, in which the still-hot preforms 10 obtained by the injection process protrude at least partially from the first mold part so that they can be picked up from the receptacles 3 defined on the cooling plate 2.

In order to allow the preforms 10 to cool down enough, the cooling plate 2 is provided with a plurality of series or arrays of receptacles 3 that are mutually spaced in a manner that corresponds to the position of the preforms 10 obtained by the injection molding device.

Obviously, the supporting bodies 23 also are arranged on the plate 22 in a manner similar to the series of receptacles 3.

Advantageously, the device 1 according to the invention provides for the possibility that at least the container or containers 4 are arranged within a confinement region 30 in which a pressure that is higher than atmospheric pressure is provided.

This pressure higher than atmospheric pressure is, for example, obtained by means of a device 31 for injecting and withdrawing air, advantageously filtered, in and from the confinement region 30.

By keeping the containers 4 (and therefore the preforms 10 accommodated therein) in a confinement region 30 with pressure higher than atmospheric pressure the risk that dirt and/or impurities might in some way contaminate the preforms is reduced substantially.

Advantageously, the confinement region 30 comprises at least one opening that can be crossed by the pick-up means 20 during the operations for storing the preforms 10 in the container 4.

Conveniently, the opening is closed by an air curtain generated by a device 32 for producing an air flow.

With reference to the embodiment shown in Figure 22, the confinement region 30 accommodates the container or containers 4.

As an alternative, as shown in Figure 23, the confinement region 30 accommodates the container or containers 4 and the pick-up means 20.

According to a further embodiment shown in Figure 24, the confinement region 30 accommodates the container or containers 4, the pick-up means 20 and the cooling plate 2.

In some cases, the confinement region can have an opening that can be closed by means of a device other than an air curtain, such as for example a shutter device.

With reference to the constructive variation shown in Figure 25, the device 1 can have means 50 for separating at least one container 4 from the confinement region 30.

Specifically, the separation means 50 are intended to separate the accommodation region of the container 4, when it is full, from the confinement region 30, so that its pick-up and replacement with a container 4 to be filled does not contaminate the confinement region 30.

By way of example, the separation means 50 can comprise at least one upper partition 53, which can be moved, on command, in order to arrange it above the access opening of the full container 4.

Advantageously, the separation means 50 have only one upper partition 53, which can move on a substantially horizontal plane in order to be arranged, in each instance, above the access opening of the container 4 to be unloaded.

Preferably, the separation means 50 have lateral partitions 51, 52.

Advantageously, there is at least one vertical dividing partition 51 arranged between the containers 4: conveniently, the vertical dividing partition 51 is fixed.

Preferably, there is at least one fixed or movable vertical partition 52 for lateral closure, and an access door 54, which is preferably associated with a respective container 4 and can be opened in order to be able to access the container to be unloaded when the fixed or movable partitions are arranged so as to isolate such container from the remaining part of the confinement region 30.

The separation means 50 can be associated, obviously, also with devices 1 that have different types of confinement regions 30 such as, for example, the ones shown in Figures 22 and 23.

Moreover, it is noted that in some embodiments the separation means 50 can define the shutter device intended to close the opening of the confinement region 30.

According to a further aspect, the present invention relates to a device 1 for unloading and storing preforms 10 for the production of containers made of plastics .

The device 1 comprises at least one cooling plate 2 that defines a plurality of receptacles 3 for respective preforms 10 and means for transferring the still-hot preforms from an injection molding device to the cooling plate 2.

The device 1 , moreover, is provided with a device for transferring the preforms 10 from the cooling plate 2 to the container 4.

Such transfer device can comprise the pick-up means 20 described previously or a traditional device comprising, for example, belt conveyors.

Advantageously, the device provides for the possibility that at least the container or containers 4 is/are arranged within a confinement region 30 in which a pressure higher than atmospheric pressure is provided.

Such pressure higher than atmospheric pressure is, for example, obtained by means of a device 31 for injecting and extracting air, advantageously filtered, in and from the confinement region 30.

By keeping the containers 4 (and therefore the preforms 10 accommodated therein) in a confinement region 30 with a pressure higher than atmospheric pressure, the risk that dirt and/or impurities might in some way contaminate the preforms is reduced substantially.

Advantageously, the confinement region 30 comprises at least one opening that can be crossed by the transfer device during the operations for storing the preforms 10 in the container 4.

Conveniently, the opening is closed by an air curtain generated by an air flow generation device 32.

With reference to the embodiment shown in Figure 22, the confinement region 30 accommodates the container or containers 4.

As an alternative, as shown in Figure 23, the confinement region 30 accommodates the container or containers 4 and the pick-up means 20.

According to a further embodiment shown in Figure 24, the confinement region 30 accommodates the container or containers 4, the pick-up means 20 and the cooling plate 2.

In some cases, the confinement region can have an opening that can be closed by means of a device other than an air curtain, such as for example a shutter device.

With reference to the constructive variation shown in Figure 25, the device 1 can have means 50 for separating at least one container 4 from the confinement region 30.

Specifically, the separation means 50 are intended to separate the accommodation region of the container 4, when it is full, from the confinement region 30, so that its pick-up and replacement with a container 4 to be filled do not contaminate the confinement region 30.

By way of example, the separation means 50 can comprise at least one upper partition 53, which can move, on command, in order to be arranged above the access opening of the full container 4.

Advantageously, the separation means 50 have a single upper partition 53, which can move on a substantially horizontal plane in order to be arranged, in each instance, above the access opening of the container 4 to be unloaded.

Preferably, the separation means 50 have lateral partitions 51, 52. Advantageously, there is at least one vertical dividing partition 51 arranged between the containers 4: conveniently, the vertical dividing partition 51 is fixed.

Preferably, there is at least one fixed or movable vertical lateral closure partition 52 and there is an access door 54, which is preferably associated with a respective container 4 and can be opened in order to be able to access the container 4 to be unloaded when the fixed or movable partitions are arranged so as to isolate said container from the remaining part of the confinement region 30.

The separation means 50 can be associated, obviously, also with devices 1 that have different types of confinement regions 30, such as, for example, the ones shown in Figures 22 and 23.

Moreover, it is noted that in some embodiments the separation means

50 can define the shutter device intended to close the opening of the confinement region 30.

Operation of the device 1 according to the invention is evidently clear from what has been described above.

In particular, at each molding cycle of the preforms by the injection molding device, the cooling plate 2 is arranged at the mold part that accommodates part of the still-hot preforms in order to transfer them into the series of receptacles 3.

While the molding device performs a new preform molding cycle, the cooling plate 2 moves away from said molding device and the pick-up means 20 proceed to pick up, from a series of receptacles 3, the respective preforms 10 in order to deposit them inside the accommodation container 4.

The cooling plate 2 is thus moved again near the molding device so that the series of receptacles, now emptied of the preforms, can receive the freshly formed preforms.

The devised solution allows a more orderly unloading of the preforms

10.

Moreover, the device according to the invention allows to reduce substantially the number of falls, rebounds and scrapings, or in any case of potential opportunities for damage to the preform independently of the temperature, with respect to the solutions commonly used with belt conveyance.

Traditional systems in fact entail a first fall onto a conveyor belt, the transfer of the preforms stacked thereon with the various preform-preform and/or preform-conveyor belt frictions, and also the last conveyor belt- storage container fall, which in traditional solutions can be improved only with the use of a further machine (soft drop) that "guides" the last fall of the preforms by entering the storage container with a sort of bucket.

The device according to the invention eliminates, moreover, one "handling" since with a single pass the preforms are transferred directly from the cooling plate to the container, with a clear reduction of the risk of damaging the preform.

Moreover, the release of the preforms within the container is far "gentler" than known solutions, since it is possible to enter the container directly with the plate that supports the preforms.

The individual characteristic presented with reference to general teachings or to particular embodiments can be all present in other embodiments or can replace characteristics in these embodiments.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims.

In practice, the materials used, so long as they are compatible with the specific use, as well as the shapes and dimensions, may be any according to requirements.

All the details may further be replaced with other technically equivalent elements.

The disclosures in Italian Patent Application No. VR2014A000184 from which this application claims priority are incorporated herein by reference.

Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.