EP4029815A1

EP4029815A1 - Handling system of sheet-like elements

Info

Publication number: EP4029815A1
Application number: EP22151606.5A
Authority: EP
Inventors: Roberto TROVI
Original assignee: Quarrata Forniture Srl
Current assignee: Quarrata Forniture Srl
Priority date: 2021-01-18
Filing date: 2022-01-14
Publication date: 2022-07-20
Anticipated expiration: 2042-01-14
Also published as: IT202100000755A1; EP4029815B1

Abstract

Described is a handling system (1) of sheet-like elements comprising:
a plurality of gripping devices (60) arranged in a matrix fashion on a lying plane (10)
each gripping device (60) of said plurality comprising a suction machine (6), designed to apply a negative pressure on a sheet-like element to be handled,
said system (1) also comprising a command and control unit configured to command and control said suction machines (6).

Description

This invention relates to a handling system of sheet-like elements.
The term sheet-like elements means all those elements, which are porous or not, such as, for example, mattresses and the sheet-like elements which make them up or other layered elements which have a substantially flat extension and are at least partly soft to touch and/or are made with a body the continuity of which is interrupted by the presence of small empty spaces or, if, for example, made of closed cell materials, they are not, if not minimally, porous.
There are currently various plants for handling the above-mentioned sheet-like elements.
These plants make particular use of roller conveyors or conveyor belts in order to transport the sheet-like element from one processing station to another.
These plants are also provided with further types of means for handling the sheet-like element which allow it to be transferred from one line to another as a function of the movement path to be followed to reach a specific processing station (or storage station for the sheet-like element).
For example, the handling means may comprise lifts or other types of lifting devices designed to move vertically to perform specific movements which would otherwise not be achievable by means of the simple roller conveyors or belts.
Disadvantageously, the handling means are bulky and limited in terms of movements, thus being "bottlenecks" from a point of view of the design of the production line and therefore from the point of view of the paths which the sheet-like element must follow.
Moreover, these plants, and in particular the handling means, are known to perform a transport which is not entirely safe for the sheet-like element which, usually resting on the roller conveyors, on a platform or more often suspended from it, could be subjected to undesired vibrations, causing the element to move relative to an optimum transport position (with the possibility of falling from the line or unsuitable infeeding into the processing station with incorrect machining and/or possibly harmful for the element or for the operators). In this regard, the Applicant had identified as particularly advantageous, in order to overcome the above-mentioned drawback, the use of handling means provided with particular grippers (in particular in the form of suction cups) operating according to the principle of the Bernoulli effect, as described in document IT102018000009365 .
In particular, the grippers use a radial flow of air which allows the lifting of the sheet-like element without using the means described above.
However, these types of prior art grippers also have drawbacks similar to those previously discussed for the prior art handling means.
In particular, these grippers do not allow the retaining of the sheet-like element to be guaranteed in an optimum transport position.
The above-mentioned grippers are able to lift the sheet-like element but are not able to guarantee the precise positioning of it.
In particular, the low friction which is created with the Bernoulli effect between the gripper and the sheet-like element in combination with the speeds and the radial accelerations of the air flow with a negative pressure generated by the Bernoulli effect cause a movement of the sheet-like element relative to an initial coupling position of the gripper.
Disadvantageously, this unguaranteed positioning may result in undesired disconnection of the sheet-like element from the gripper, as well as incorrect positioning in the respective processing station or roller conveyor.
Further important drawbacks of the grippers which use the Bernoulli effect for the movement consist in the fact that just the negative pressure generated by the gripper is not sufficient to safely move sheet-like elements having large weights per square metre and thicknesses (greater than 3-4 cm) unless very high pressures of the compressed air are used, with a consequent high energy consumption.
The term "safe movement" means a secure gripping of the sheet-like element by the gripper and the total absence of relative movement between the sheet-like element and the gripper.
Further prior art handling systems involve the use of a plurality of suction cups positioned on a common lying plane and powered by a single source of suction air. However, this prior art solution is also not free of major drawbacks.
A first major drawback is due to the fact that since all the suction cups are connected to a single power source, if, for example, one or more suction cups are not occupied by the sheet-like element to be moved, there is a suction flow continuously through this which tends to reduce and worsen the efficiency of the suction system as a whole.
A further drawback of this prior art type of suction system is due to the fact that since there is no possibility of individually modulating the suction power of the suction cups the field of use of the system is reduced.
The technical purpose of the invention is therefore to provide a handling system of sheet-like elements which is able to overcome the above-mentioned drawbacks in the prior art.
The aim of the invention is therefore to provide a handling system of sheet-like elements which allows the positioning of the sheet-like element to be guaranteed. A further aim of the invention is to provide a handling system of sheet-like elements which allows any type of material and/or thickness and/or geometrical shape of a sheet-like element to be handled.
The technical purpose indicated and the aims specified are substantially achieved by a handling system of sheet-like elements comprising the technical features described in one or more of the appended claims.
The dependent claims can correspond to alternative embodiments of the invention.
Further features and advantages of the invention are more apparent in the non-limiting description which follows of a preferred non-exclusive embodiment of a handling system of sheet-like elements.
The description is set out below with reference to the accompanying drawings which are provided solely for purposes of illustration without restricting the scope of the invention and in which:

Figure 1 is a schematic perspective view of a plant comprising a handling system of sheet-like elements according to the invention;
Figure 2 is a schematic perspective view of a handling system of sheet-like elements;
Figure 3 is a schematic perspective view of one of the plurality of gripping devices of a handling system of sheet-like elements according to the invention and
Figure 4 is a schematic cross section view of a gripping device according to the invention.

With reference to the accompanying drawings, the numeral 1 denotes in its entirety a handling system of sheet-like elements which, for simplicity of description, will hereafter be referred to as the system 1.
Figure 1 schematically illustrates a plant 100 comprising a system 1 according to the invention.
The plant 100 comprises respective lifting members 101 operatively connected to the system 1 in such a way as to lift it with or without a sheet-like element retained by it.
Advantageously, in a position below the system 1, the plant 100 comprises a conveyor belt 102 or a roller conveyor for suitably positioning a sheet-like element in such a way as to be then handled by the system 1. The term "sheet-like elements" means all those elements, which are porous or not, such as, for example, mattresses or other layered elements, which have a flat extension and are at least partly soft to touch.
The handling system 1 of sheet-like elements according to the invention comprises a plurality of gripping devices 60 positioned in a matrix fashion on a lying plane 10 as shown in Figure 2.
Each gripping device 60 comprises a suction machine 6 which is designed to apply a negative pressure (by means of an air suction) on a sheet-like element to be handled. The system 1 also comprises a command and control unit (not illustrated in the drawings) configured to control and control the operation of the suction machines 6. The term "command and control" means the capacity of the unit to activate also individually the various suction machines 6 as well as individually modulating the suction power.
The modulation of the power of each single suction machine 6 allows the system 1 to be also used with sheet-like elements having small thicknesses and/or made of very breathable materials.
Advantageously, the suction machine 6 comprises a conveyor 2 having a working mouth 3 configured to move towards the sheet-like element so as to move it thanks to the force generated by the suction air.
The conveyor 2 is substantially frustoconical in shape with the smaller base positioned at the working mouth 3. The substantially frustoconical shape makes it possible to optimise the flow of air sucked in to increase the gripping force relative to the sheet-like element.
With reference to Figures 3 and 4, the suction machine 6 comprises an impeller 4 connected to a respective electric motor 7.
The impeller 4 and the electric motor 7 are therefore located entirely inside the conveyor 2.
As mentioned above, the command and control unit selectively and independently controls each of the suction machines 6 both in terms of enabling (ON/OFF) and in terms of modulation of the suction power. Advantageously, the conveyor 2 comprises, at the mouth 3, an annular support portion 11 configured to approach and deform the material of the sheet-like element.
The deformation caused by the support portion 11 makes it possible to optimise the overall suction function, in fact reducing to a minimum the head losses. Advantageously, the conveyor 2 also comprises a portion 13 positioned outside the mouth 3 and comprising a plurality of pins 12.
The pins 12 are positioned parallel to the main axis of extension of the conveyor 2 and are designed to retain, relative to transversal forces, the sheet-like element being processed.
The pins 12 are configured to be inserted inside the sheet-like element without, however, adversely affecting the quality.
The pins 12 allow an excellent grip of the sheet-like element to be guaranteed even when subjected to accidental translations, for example during the steps of handling at high speeds or overturning of the sheet-like elements.
Advantageously, moreover, the support portion 13 has a plurality of fixing means 14, for example threaded connections or rivets, configured for stably fixing the suction machine 6 to the lying plane 10.
In the system 1 according to the invention, the plurality of gripping devices 60 is not connected to a single air supply source, but each single suction machine 6 has its own air suction source (motor and impeller). Advantageously, the system 1 also comprises a plurality of needles 5 configured to emerge directly from the lying plane 10.
The needles 5 emerge from the lying plane with different inclinations.
Both the gripping devices 60 and the needles 5 can be operated selectively in such a way as to obtain an operation of the system 1 which alternatively:

activates only the gripping devices 60,
activates only the needles 5 or
activates both the gripping devices 60 and the needles 5.

The above-mentioned different operating modes allow the system 1 to be used on a multiplicity of types of sheet-like elements, both with regard to different materials and different weights and dimensions.
Advantageously, the system 1 also comprises magnetic means distributed also distributed on the lying plane 10.
The magnetic means allow the system 1 to move in an optimised manner, for example, mattresses comprising metal springs inside since the latter are attracted by the magnetic means.
Advantageously, the needles 5 are also positioned in a matrix fashion on the lying plane 10.
The needles 5 are also advantageously distributed interposed between themselves in an equidistant fashion and interposed between the gripping devices 6. Advantageously, the needles 5 are actuated by an air supply source.
As shown in Figure 2, the needles 5 are arranged according to respective rows 8a, 8b each of which comprises a plurality of needles 5 having the same inclination to each other.
In particular, advantageously, each gripping device 60 is interposed between a first row of needles 8a (having the same inclination to each other) and a second row of needles 8b (having the same inclination to each other but different from that of the row 8a).
The system 1 also advantageously comprises an actuator, not illustrated in the drawings, configured to simultaneously activate an entire row 8a or 8b of needles 5.
According to this solution, all the needles 5 of a same row 8a or 8b emerge simultaneously from the lying plane 10 since they are driven by a single actuator.
The actuator may be made in the form of a rigid bar also moved by the source of compressed air.
The lying plane 10 of the system 1 comprises a plurality of gripping devices 60 as described above and located in such a way as to guarantee the gripping of a sheet-like element as a function of its weight and/or dimensions. According to the embodiment of the system 1 shown in the drawings, this comprises a plurality of gripping devices 60 positioned according to a distribution in a matrix fashion.
The distribution in a matrix fashion allows the system 1 to act in a homogeneous manner on the sheet-like element, guaranteeing a secure gripping of the sheet-like element.
In use, by means, for example, of the conveyor belt 102 of the plant 100 a porous sheet-like element is positioned below the system 1.
At this point, the plant 100 moves the system 1 towards the sheet-like element which, by means of the suction generated by each single suction machine 6, allows the movement.
Advantageously, the command and control unit of the suction machines 6 allows only those which are actually in contact with the sheet-like element to be handled to be enabled.
At this point, the system 1 is able to move the sheet-like element between the various operating positions, guaranteeing the correct transport and perfect positioning of the sheet-like element.
Moreover, the system 1 is able to handle the sheet-like element in such a way that it can be moved from a flat configuration to a vertical configuration or vice versa as it is able to move the sheet-like element whilst maintaining the flat or vertical configuration.
In other words, the gripping device 60 is able to create a vacuum which allows the coupling for handling the sheet-like element.
Advantageously, a further embodiment of the system 1 according to the invention also comprises active or passive means for reducing the operating noise of the gripping devices 60.
As regards the means for reducing active noise, a first embodiment comprises a generator of one or more sound waves designed to interfere with the sound waves generated by the individual suction machines 6 in such a way as to eliminate or in any case reduce the acoustic emissions in an appreciable manner.
The above-mentioned generator comprises, for example, an acoustic loudspeaker.
A further embodiment of the means for reducing the noise of an active type comprises a generator of a flow of a fluid, for example air, designed to move the sound waves generated by the suction machines 6 "mechanically".
On the other hand, the means for reducing the noise of an passive type comprise sound-absorbent materials constituting parts of the suction machine 6 (for example, the body of the conveyor) and/or ducts for discharging the sucked air to be applied to the conveyor 2 in such a way that they obstruct the propagation of the noise generated.
One solution, for example, involves the use of an outfeed duct made of sound-absorbent material and having a labyrinth-shaped cross section.
It is known that the sound waves propagate linearly in the environment and if they encounter physical obstacles tend to lose their intensity.
In short, according to the prior art handling systems of sheet-like elements, for example for sheets of glass, ceramic or metal, the suction source consists of a single vacuum pump or in any case a pump designed to control a plurality of gripping points.
In the case of the above-mentioned materials, since they are not breathable or porous, the gripping points in the prior art systems are able to carry out a secure grip on the surface of the sheet-like element.
This translates into the fact that the vacuum pump is able to rapidly generate a level of vacuum sufficient for handling the sheet-like element.
This speed of entry into operation is due to the fact that the volume of the suction cup (gripping points) in which the vacuum is generated by the pump is minimal and there are no head losses thanks to the characteristics of the materials to be lifted, which are substantially flat and not breathable or porous.
According to the prior art systems for materials which are not breathable or porous, pipes with small diameter are therefore sufficient for connection between the vacuum pump and the gripping points.
In the case of sheet-like elements according to the invention, these have various defects for the purpose of a good gripping by the system 1.
In particular, the sheet-like elements have or may have a high planar discontinuity in the gripping surface or even breathability and/or porosity of the material. Therefore, it is not possible, for these types of material, to generate a high level of vacuum which is able to guarantee an adequate grip since the contact between the gripping points and the sheet-like element is often anything but hermetically sealed.
For this reason, this invention describes a high volume system with a low vacuum level unlike what is applied with the prior art systems (for example for smooth materials such as glass or metals) where a low volume and high vacuum level is used.
In order to generate a large volume of air sucked in as required in the invention, large pumps and pipes with a large diameter would be necessary.
In short, for each gripping point (working mouth 3) it would be necessary to use a large diameter pipe, thus increasing weights and dimensions of the entire system. It should also be noted that the sheet-like elements can be extremely flexible, therefore, if just a few gripping points are used they would not be kept perfectly horizontal during vertical movements.
The high number of gripping points (a possible configuration is shown in Figure 2) for a system 1 according to the invention is as follows: in a lying plane 10 having dimensions 2 metres x 2 metres (4 square metres) there are 49 gripping points (according to a 7x7 matrix).
In the case of use of a high vacuum level system, as in the prior art systems, 49 conduits would be necessary for the air with a diameter of at least 60 millimetres each, all positioned above the lying plane 10.
The presence of such a large number of large diameter conduits makes the system heavy, complex and bulky, in practice unmanageable from a point of view of movement (translation, rotation, tipping).
This problem is resolved by the invention with the use of individual and independent suction machines 6 positioned on the lying plane 10.
The suction machines 6 are very small components which only require an electrical power supply cable for a correct operation.
The handling system 1 according to the invention is able to overcome the drawbacks of the prior art.
A first important advantage consists in the fact that the system 1 according to the invention is able to retain the sheet-like element in an optimum manner thanks to the suction force generated by each single suction machine 6 thus guaranteeing a safe transport of the sheet-like element.
Moreover, the system 1 according to the invention allows different types of material, different thicknesses as well as different geometrical shapes of the sheet-like element to be handled, enabling in a predetermined manner the actuation of only the gripping devices 60 which are actually covered by the area of the sheet-like element to be handled.
Moreover, a further advantage consists in the possibility of modulating the suction power of each single gripping device 60 in such a way as to optimise the overall suction force as a function of the specific sheet-like element to be handled.

Claims

A handling system (1) of sheet-like elements comprising:
a plurality of gripping devices (60) arranged in a matrix fashion on a lying plane (10) each gripping device (60) of said plurality comprising a suction machine (6), designed to apply a negative pressure on a sheet-like element to be handled, said suction machine (6) comprising a conveyor (2) having an operating mouth (3) configured to move towards said sheet-like element,

said conveyor (2) having a substantially frustoconical shape with the smaller base at said working mouth (3), said system (1) also comprising a command and control unit configured to control said suction machines (6) said system (1) being characterised in that said suction machine (6) comprises an impeller (4) connected to a respective electric motor (7), said impeller (4) and said electric motor (7) being positioned inside said conveyor (2).
The system (1) according to claim 1, wherein said command and control unit selectively and independently controls each of said suction machines (6) .
The system (1) according to claim 1, wherein said conveyor (2) comprises an annular support portion (11) at said working mouth (3) configured to approach and deform in support said sheet-like element.
The system (1) according to any one of the preceding claims, wherein said conveyor (2) has a portion (13) positioned outside said mouth (3) and comprising a plurality of pins (12) positioned parallel to the main axis of extension of said conveyor (2), said pins (12) being designed to retain, relative to transversal forces, said sheet-like element being processed.
The system (1) according to the preceding claim, wherein said portion (13) has a plurality of fixing means (12) configured for stably fixing said suction machine (6) to said lying plane (10).
The system (1) according to any one of the preceding claims, also comprising a plurality of needles (5) configured to emerge from said lying plane (10), said needles (5) emerging with different inclinations, said gripping devices (60) and said needles (5) being selectively operable in such a way as to obtain an operation of said system (1) with alternatively active only said gripping devices (60), only said needles (5) or both said gripping devices (60) and said needles (5).
The system (1) according to claim 1, also comprising a plurality of magnetic means positioned in a matrix fashion on said lying plane (10) and distributed equally spaced and interposed between said gripping devices (60) and said needles (5).
The system (1) according to any one of the preceding claims, also comprising means for reducing the noise generated by said suction machines (6) designed to obstruct the propagation of the sound waves emitted during their operation.