WO2019097443A1

WO2019097443A1 - Gripper for the grip of loads

Info

Publication number: WO2019097443A1
Application number: PCT/IB2018/058995
Authority: WO
Inventors: Fabio RUINI; Andrea GORRIERI
Original assignee: Simac Tech S.R.L.
Priority date: 2017-11-15
Filing date: 2018-11-15
Publication date: 2019-05-23

Abstract

The gripper (1) for the grip of loads comprises: a main frame (2) associable with a machine for the movement of loads (51); an individual holding top (4) for holding at least one load (3), lying on a work top (A) substantially horizontal and associated with the main frame (2) in a sliding manner along a first work direction (B) which is substantially horizontal in order to arrange itself below the load (3) so as to support it; lateral suction means (5) provided with at least a first suction element (6) of the load (3), associated with the main frame (2) in a sliding manner along a second work direction (C) which is substantially vertical and adapted to lift at least one lateral portion of the load (3) in a lifting configuration in which the holding top can be inserted in a sliding manner below the load (3); upper retention means (7) of the load (3), associated with the main frame (2) in a sliding manner along a third work direction (D) which is substantially vertical and adapted to retain the top of the load (3) supported by the holding top (4).

Description

GRIPPER FOR THE GRIP OF LOADS

Technical Field

The present invention relates to a gripper for the grip of loads.

Background Art

Various grippers are known for the grip of loads which are widely used in picking processes to carry out automated palletizing and/or de-palletizing operations.

The companies that deal with these operations receive from a large number of suppliers a large quantity of products that have to be sorted, for example on different pallets, to be then delivered to the corresponding customers, such as e.g. supermarkets.

Generally, the products to be sorted are packaged in packs, or loads, of various kind and arranged in an orderly manner on pallets to be transported easily.

Specifically, the loads to be sorted are arranged one next to the other to form different layers of products stacked on one another so as to place the largest number of loads on a single pallet.

The use of known grippers makes it possible to recover one or more loads from one pallet and place them in an orderly manner on one another, carrying out the palletizing and de-palletizing operations in a precise, fast and automatic way that would otherwise be performed manually for each pallet with consequent increase in work times.

Generally, the known grippers are attached to the end of an anthropomorphic robot and comprise two sheet-like jaws, arranged substantially opposed and parallel to each other, and moveable with respect to each other to form a vice which is able to firmly grasp the loads to be moved.

Specifically, the robot arranges the jaws sideways with respect to the load to be moved and moves them close to each other so as to apply to the sides of the load a predefined pressure which is sufficient to allow the gripper to firmly grasp the load.

In this way, the robot can lift the load which remains trapped between the jaws of the gripper and can be arranged on another pallet in an orderly manner. Moreover, the grippers of known type employ suction means, generally arranged between the two jaws and positioned in such a way as to face the load to be lifted upwards or laterally.

In this way, the suction means provide a higher gripping point of the load which, in conjunction with the lateral gripping points provided by the jaws, increases the maximum capacity of the gripper.

Grippers of this type are shown, e.g., in patent documents IT2014MO0054 and US20070280812.

Nevertheless, the known grippers for the grip of loads do have some drawbacks related to the maximum load carried and to the variety of moveable loads.

In fact, in the event it being necessary to de-palletize particularly heavy loads, the lateral grip of the grippers and the upper grip of the suction means are not enough to lift and move the load safely.

Moreover, the grippers of this type have difficulty in firmly grasping loads of a particular shape, such as e.g. cardboard trays open at the top, on which the suction means have no grip and the grip of the jaws is considerably reduced. Furthermore, as previously mentioned, the loads positioned on the pallets are generally juxtaposed to each other so as to maximize the number of loads placed on a single pallet.

Consequently, the robot must apply on the grippers a force which is sufficient to allow the jaws to slip between one load and the other so as to forcibly separate them and grasp the desired load.

However, the repetition of this operation ends up damaging the loads with the risk of losing their contents and with the consequent slowing down or interruption of the palletizing and de-palletizing operations.

Description of the Invention

The main aim of the present invention is to devise a gripper for the grip of loads that allows grasping a large variety of loads irrespective of their shape and size. Another object of the present invention is to devise a gripper for the grip of loads that allows grasping loads without damaging them.

Another object of the present invention is to devise a gripper for the grip of loads which allows overcoming the aforementioned drawbacks of the prior art within the scope of a simple, rational, easy, efficient to use and cost-effective solution.

The aforementioned objects are achieved by the present gripper for the grip of loads having the characteristics of claim 1.

Brief Description of the Drawings

Other characteristics and advantages of the present invention will become more evident from the description of a preferred, but not exclusive embodiment of a gripper for the grip of loads, illustrated by way of an indicative, but non limiting example, in the attached drawings in which:

Figure 1 is an axonometric view of the gripper according to the invention;

Figures 2 to 6 show, in a sequence of side views and axonometric views, the operation of the gripper according to the invention.

Fmbodiments of the Invention

With particular reference to these illustrations, reference numeral 1 globally indicates a gripper for the grip of loads.

The gripper 1 comprises:

at least one main frame 2 associable with a machine for the movement of loads 51 ;

an individual holding top 4 for holding at least one load 3, lying on a work top A substantially horizontal and associated with the main frame 2 in a sliding manner along a first work direction B which is substantially horizontal in order to arrange itself below the load 3 so as to support it; lateral suction means 5 provided with at least a first suction element 6 of said load 3, associated with the main frame 2 in a sliding manner along a second work direction C which is substantially vertical and adapted to lift at least one lateral portion of the load 3 in a lifting configuration in which the holding top 1 can be inserted in a sliding manner below the load 3;

upper retention means 7 of the load 3, associated with the main frame 2 in a sliding manner along a third work direction D which is substantially vertical and adapted to retain the top of the load 3 supported by the holding top 4. In the following description the term load 3 is meant to indicate a bundle comprising six plastic bottles arranged adjacent to each other along two rows of three bottles each as shown in Figure 1, wherein a plurality of loads 3 are arranged on a support 8, which in this case is a pallet.

In particular, the load 3 intended in this way is considered particularly significant for the description of the gripper 1 since, in most cases, the shape of the bottles makes the shape of the load 3 substantially irregular and complicates the grip of the load 3 by the gripper 1.

It should be taken into consideration, however, that the load 3 could be of different shape and size or of a different type, e.g. such as a cardboard pack and/or packaging.

Furthermore, in the remainder of the following discussion, the terms “horizontal” and“vertical” as well as the terms“upper” and“lower” are used with reference to the conditions of normal use of the gripper 1 shown in Figure 1, i.e. those in which the main frame 2 is attached to the machine for the movement of loads 51 and in which the holding top 4 and the corresponding work top A are arranged substantially parallel to the ground.

Specifically, the gripper 1 comprises at least one attachment surface 9 obtained on top of the main frame 2 and adapted to attach to an attachment end 10 of the machine for the movement of loads 51.

Preferably, the attachment end 10 of the machine for the movement of loads 51 is inserted by interlocking in a substantially orthogonal manner to the attachment surface 9 as shown in Figure 1.

Advantageously, the gripper 1 comprises at least one guide system 11, 48, 49, 50 comprising at least one horizontal worm screw 48 associated with the main frame 2 along the first work direction B and at least a nut-screw member 50 coupled to the horizontal worm screw 48 and with which the holding top 4 is associated.

Moreover, the guide system 11, 48, 49, 50 comprises at least one pair of horizontal guides 11 through which the holding top 4 is guided sliding along the first work direction B and a pair of horizontal rails 49 associated with the main frame 2 and with which the holding top 4 is associated in a sliding manner along the first work direction B. Conveniently, the attachment surface 9 and the guide systems 11, 48, 49, 50 are arranged substantially opposite each other with respect to the main frame 2.

In fact, the attachment surface 9 is formed on top of the main frame 2 to allow the attachment thereof with the attachment end 10, while the guide system 11, 48, 49, 50 is located below the main frame 2.

Accordingly, the holding top 4 and the attachment surface 9 are substantially parallel to each other and substantially parallel to the ground in the normal conditions of use of the gripper 1.

Conveniently, the holding top 4 is sliding in a retractable manner between a projecting configuration, in which the holding top 4 extends overhanging from the main frame 2, and a retracted configuration, in which the holding top 4 is retracted adjacent to the main frame 2.

Preferably, the holding top 4 is a substantially flat metal sheet which slides inside the rectilinear guide 11 so as to switch from the retracted configuration, shown in Figures 1, 2 and 3, to the projecting configuration, shown in Figures 4, 5 and 6, and vice versa.

Conveniently, the gripper 1 comprises at least one linear motor 12 mounted on the main frame 2 and associated with the horizontal worm screw 48 to rotate it so as to move the holding top 4 inside the horizontal guides 11 between the projecting configuration and the retracted configuration.

Moreover, the holding top 4 comprises at least one end portion 13 substantially pointed and having inclined sides 14 for guiding the insertion underneath the load 3.

Preferably, the inclined sides 14 are of substantially equal length and are substantially contiguous to each other in the apex of the tip of the holding top 4 where they form an angle of 90°.

Moreover, the holding top 4 is substantially symmetrical with respect to a straight line substantially parallel to the first work direction B and passing through the apex of the tip of the end portion 13. Conveniently, the gripper 1 comprises at least one guide assembly 15, 16, 17 which is associated with the main frame 2, extends along the second work direction C and lies on top of the work top A, the lateral suction means 5 being associated in a sliding manner with the guide assembly 15, 16, 17.

Preferably, the guide assembly 15, 16, 17 comprises at least a first worm screw 16 associated with the main frame 2 along the second work direction C and at least a first nut- screw body 17 coupled to the first worm screw 16 and with which the lateral suction means 5 are associated.

Moreover, the guide assembly 15, 16, 17 comprises at least one pair of first vertical rails 15 mounted on the main frame 2 substantially parallel to the first worm screw 16 and with which the first nut-screw body 17 is associated in a sliding manner along the second work direction C.

Conveniently, the gripper 1 comprises at least a first rotary actuator 18 mounted on the main frame 2 and associated with the first worm screw 16 to rotate it so as to move the first nut- screw body 17 and with it also the lateral suction means

5.

Advantageously, the gripper 1 comprises at least one guide unit 19, 20, 21 which is associated with the main frame 2, extends along the third work direction D and lies on top of the work top A, the upper retention means 7 being associated in a sliding manner with the guide unit 19, 20, 21.

Preferably, the guide unit 19, 20, 21 comprises at least a second worm screw 20 associated with the main frame 2 along the third work direction D and at least a second nut- screw body 21 coupled to the second worm screw 20 and with which the upper retention means 7 are associated.

Moreover, the guide unit 19, 20, 21 comprises at least a pair of second vertical rails 19 mounted on the main frame 2 substantially parallel to the second worm screw 20 and with which the second nut- screw body 21 is associated in a sliding manner along the third work direction D.

Conveniently, the gripper 1 comprises at least a second rotary actuator mounted on the main frame 2 and associated with the second worm screw 20 to rotate it so as to move the second nut- screw body 21 and with it also the upper retention means 7.

Advantageously, the guide assembly 15, 16, 17 and the guide unit 19, 20, 21 are arranged substantially side by side.

In particular, the first worm screw 16 of the guide assembly 15, 16, 17 and the second worm screw 20 of the guide unit 19, 20, 21 are arranged substantially lying onto a front plane substantially orthogonal to the first work direction B. Furthermore, it is preferable to arrange the first worm screw 16 and the second worm screw 20 close to each other so as to occupy little space on board the main frame 2 and make the guide assembly 15, 16, 17 and the guide unit 19, 20, 21 in a compact manner.

Accordingly, the lateral suction means 5 and the upper retention means 7 are mounted on the main frame 2 one below the other respectively, and at the same time sliding substantially side by side to make a compact arrangement of the lateral suction means 5 and the upper retention means 7.

Conveniently, the first suction element 6 is moveable along a fourth horizontal work direction G to fasten to the load 3.

Preferably, the first suction element 6 is of the type of a pneumatic sucker and comprises a first substantially flat suction surface, which is arranged substantially orthogonal to the fourth work direction G and is adapted to fasten to the load 3.

In particular, the gripper 1 comprises at least a first rectilinear actuator 23 mounted on the first nut-screw body 17 and associated with the first suction element 6 to move it along the fourth work direction G.

Advantageously, the lateral suction means 5 comprise at least a second suction element 24 sliding along a fifth work direction H which is horizontal and substantially orthogonal to the fourth work direction G, the load 3 comprising at least a first side 25 and at least a second side 26 substantially orthogonal to each other and the first suction element 6 and the second suction element 24 being able to fasten to the first side 25 and to the second side 26, respectively.

Preferably, the load 3 comprises two first sides 25 and two second sides 26 adjacent to each other and interposed between a lower face 27 adapted to hold the load 3 on the support 8 and an upper face 28 substantially opposed and parallel to the lower face 27.

In particular, the lower face 27 is of substantially rectangular shape and substantially equal to the upper face 28 and the first sides 25 and the second side 26 are arranged in two by two substantially opposed and parallel to each other so as to form a closed body with a substantially rectangular cross-section with the lower face 27 and the upper face 28.

With reference to the type of load 3 taken into account for the description of the gripper 1, the term first side 25 is meant to indicate the side of the load 3 substantially defined by the extension of two bottles placed side by side, the term second side 26 is meant to indicate the side of the load 3 substantially defined by the extension of three bottles aligned one next to the other, while the term lower face 27 is meant to indicate the base of the load 3 substantially defined by the supporting surface of the six bottles and the term upper face 28 is meant to indicate the top of the load 3 substantially defined by the necks of the six bottles.

It is in fact underlined that, given the nature of the load 3, the first sides 25, the second sides 26, the upper face 28 and the lower face 27 are substantially irregular, i.e. they are not perfectly flat.

In particular, given the shape of the bottles, the load 3 comprises various protrusions 29, above all at the necks of the bottles which define the upper face 28.

Preferably, the second suction element 24 is of the type of a pneumatic sucker and comprises a second substantially flat suction surface, arranged substantially orthogonal to the fifth work direction H and adapted to fasten to the load 3.

In particular, the gripper 1 comprises at least a second rectilinear actuator 30 mounted on the first nut-screw body 17 and associated with the second suction element 24 to move it along the fifth work direction H.

Conveniently, the upper retention means 7 comprise at least one counteracting member 31 which projects overhanging from the guide unit 19, 20, 21 and having at least a lower portion 32 which can be placed in contact with the top of the load 3 and adapted to press the load 3 against the holding top 4, by applying a predefined pressure value.

Preferably, the counteracting member 31 extends along the first work direction B starting from the guide unit 19, 20, 21 and is provided with a first end associated with the second nut-screw body 21 and with a second suspended end, opposite the first end and comprising the lower portion 32, which is oriented towards the ground and facing the work top A.

Moreover, the lower portion 32 is substantially flat and, when the holding top 4 is in the projecting configuration, is substantially opposed and parallel to the holding top 4.

Conveniently, the upper retention means 7 comprise at least one upper suction element 33 which can be fastened to the top of the load 3.

Preferably, the upper suction element 33 is of the type of a suction plane and comprises a substantially flat abutment portion adapted to contact the upper face 28 of the load 3.

In particular, the upper suction element 33 is made of an elastically deformable material to adapt to the shape of the load 3 when pressed against the load 3. Furthermore, the upper suction element 33 coincides with the lower portion 32 of the counteracting member 31.

This allows the upper suction element 33 to contact the upper face 28 and to fasten to the load 3 despite the protrusions 29 produced by the necks of the bottles.

Advantageously, the upper retention means 7 comprise at least one lateral containment element 34 of the load 3.

Conveniently, the lateral containment element 34 is associated with the counteracting member 31 in a sliding manner along a first sliding direction E substantially horizontal and orthogonal to the first work direction B.

Preferably, the gripper 1 comprises at least one horizontal guide 35, 36 provided with at least one horizontal rail 35 associated with the counteracting member 31 and at least one sliding element 36 inside the horizontal rail 35 and associated with the lateral containment element 34. Moreover, the gripper 1 comprises a horizontal actuator 37 mounted on the upper retention means 7 and associated with the sliding element 36 in order to move the lateral containment element 34 along the first sliding direction E. Furthermore, the lateral containment element 34 is associated with the counteracting member 31 in a sliding manner along a second sliding direction F which is substantially vertical.

Preferably, the gripper 1 comprises at least one vertical actuator 38 interposed between the sliding element 36 and the lateral containment element 34.

In this way, the vertical actuator 38 moves the lateral containment element 34 vertically along the second sliding direction F substantially orthogonal to the first sliding direction E.

In particular, the lateral containment element 34 is integral in translation to the counteracting member 31 along the third work direction D and, at the same time, is moveable with respect to the counteracting member 31 vertically along the first sliding direction E and horizontally along the second sliding direction F.

Conveniently, the lateral containment element 34 comprises at least two sheets 39 which are substantially vertical and arranged substantially orthogonal to each other.

Furthermore, a sheet 39 defines a first lateral containment plane which is substantially vertical and substantially opposed and parallel to the first suction surface of the first suction element 6 and the other sheet 39 defines a second lateral containment plane which is substantially vertical and substantially opposed and parallel to the second suction surface of the second suction element 24.

Preferably, the lateral containment element 34 comprises at least one horizontal adjustment bracket 40 for adjusting the sheets 39 and at least one pair of vertical adjustment brackets 41 for adjusting the sheets 39.

Specifically, the horizontal adjustment bracket 40 is a horizontal metal sheet, substantially flat and interposed between the vertical actuator 38 and the lateral containment element 34, and the vertical adjustment bracket 41 is an angular metal sheet, provided with a first face associated with the horizontal adjustment bracket 40 and with a second face substantially orthogonal to the first face and associated with one of the sheets 39.

In other words, each vertical adjustment bracket 41 is interposed between the horizontal adjustment bracket 40 and one of the sheets 39 which, in this way, are arranged substantially orthogonal to the horizontal adjustment bracket 40 and to the work plane A.

Preferably, the gripper 1 comprises horizontal adjustment means 42, 44, interposed between the horizontal adjustment bracket 40 and the vertical adjustment brackets 41, and vertical adjustment means 45, 47, interposed between the vertical adjustment brackets 41 and the corresponding sheets 39. Advantageously, the horizontal adjustment means 42, 44 and the vertical adjustment means 45, 47 allow adjusting the position of the sheets 39 with respect to the counteracting member 31.

Specifically, the horizontal adjustment means 42, 44 allow fixing the position of a sheet 39 substantially along the fourth work direction G and of the other sheet

39 substantially along the fifth work direction H.

The vertical adjustment means 45, 47, on the contrary, allow fixing the position of both sheets 39 substantially along the second work direction C.

Preferably, the horizontal adjustment means 42, 44 comprise a plurality of horizontal rectilinear openings 42 formed on the horizontal adjustment bracket

40 and a plurality of vertical circular holes made on the first face of the vertical adjustment brackets 41 at the horizontal rectilinear openings 42.

In particular, the horizontal rectilinear openings 42 are made substantially parallel in pairs of two, each pair being made substantially orthogonal to the other so as to associate the sheets 39 orthogonally with each other.

Furthermore, the horizontal adjustment means 42, 44 comprise a plurality of vertical pins 44, each of which passes through a horizontal rectilinear opening 42 and a vertical circular hole so as to fix the horizontal adjustment brackets 40 to the first face of the vertical adjustment brackets 41.

Similarly to the horizontal adjustment means 42, 44, the vertical adjustment means 45, 47 comprise a plurality of vertical rectilinear openings 45 formed on the sheets 39 and a plurality of horizontal circular holes made on each of the second faces of the vertical adjustment brackets 41.

In particular, the vertical rectilinear openings 45 are made substantially parallel in pairs of two on each sheet 39 and the horizontal circular holes are made in pairs of two on each second face of the vertical adjustment bracket 41 at the vertical rectilinear openings 45.

Furthermore, the vertical adjustment means 45, 47 comprise a plurality of horizontal pins 47, each of which passes through a vertical rectilinear opening 45 and a horizontal circular hole so as to fix a sheet 39 to each second face of the vertical adjustment brackets 41.

The operation of the invention is as follows.

Conveniently, the vertical pins 44 are arranged inside the corresponding vertical circular holes through the corresponding horizontal rectilinear openings 42, which slide horizontally along the vertical pins themselves.

In this way, once the position of the horizontal rectilinear openings 42 has been set, the vertical pins 44 are fixed to the horizontal adjustment bracket 40 and to the vertical adjustment brackets 41 so as to block the mutual position thereof and, in other words, adjust the position of the sheets 39 horizontally along the first work direction B.

Similarly, the horizontal pins 47 are arranged inside the corresponding horizontal circular holes through the corresponding vertical rectilinear openings 45, which slide vertically along the vertical pins 44 themselves.

In this way, once the position of the vertical rectilinear openings 45 has been set, the horizontal pins 47 are fixed to the vertical adjustment bracket 41 and to the sheets 39 so as to block the mutual position thereof and, in other words, adjust the position of the sheets 39 vertically along the third work direction D.

In particular, the adjustment of the sheets 39 carried out in this way is made beforehand, e.g. by an operator, according to the characteristics of the loads 3 to be palletized or de-palletized and is substantially fixed, i.e. it cannot be changed during the operation of the gripper 1. Alternative embodiments cannot however be ruled in which the adjustment of the position of the sheets 39 can be carried out by means of the horizontal adjustment means 42, 44 and the vertical adjustment means 45, 47 in an automated manner also during the operation of the gripper 1, e.g. by using one or more motors associated with the sheets 39.

More in detail, this type of adjustment allows adapting the position of the sheets 39 according to the size of the loads 3 to be grasped, for example in the case wherein the loads 3 comprise six half-liter bottles or six two-liter bottles, and/or according to the shape of the loads 3 to be grasped, for example in the case wherein the bottles are provided with a very narrow and elongated neck or a very wide and short neck.

In particular, the lateral containment element 34 is preferably used to retain bundles of bottles or loads 3 having shapes and size similar to those of bundles of bottles.

It cannot however be ruled out that the sheets 39 are adjustable by using the vertical adjustment means 45, 47 and the horizontal adjustment means 42, 44 so as to allow using the lateral containment element 34 also to grip loads 3 having a substantially different shape from those of the type of a bundle of bottles.

Once the sheets 39 have been adjusted, the gripper 1 is moved close to the load 3 by the machine for the movement of loads 51.

In particular, the first suction element 6 and the second suction element 24 are arranged facing a first side 25 and a second side 26 respectively of one of the loads 3.

At the same time, given the mutual position of the holding top 4 and of the attachment surface 9 with respect to the main frame 2, the work top A is arranged at the lower face 27 of the load 3 as shown in Figure 2.

When this position has been reached, the first rectilinear actuator 23 moves the first suction element 6 close to the first side 25 along the fourth work direction G.

Similarly, the second rectilinear actuator 30 moves the second suction element 24 along the fifth work direction H close to the second side 26. In this way, when the first suction element 6 and the second suction element 24 come into contact with the load 3, they attach to the first side 25 and to the second side 26 respectively.

After having attached the first suction element 6 and the second suction element 24, the first rotary actuator 18 moves the lateral suction means 5 along the second work direction C away from the work top A.

In this way, the first suction element 6 and the second suction element 24 slide upwards and raise the loads 3, the lower face 27 of which lifts, even only partially, and reaches a substantially higher level than the level of the work top

A.

In this position, the linear motor 12 moves the holding top 4 which slides from the retracted configuration to the projecting configuration.

In particular, the holding top 4 is inserted below the lower face 27 so as to support the load 3 retained by the lateral suction means 5.

Advantageously, the sliding of the holding top 4 below the load 3 is facilitated by the inclined sides 14 which act as a guide for the lower face 27.

Moreover, since the inclined sides 14 are orthogonal to each other, the end portion 13 can be positioned below the load 3 so as to arrange the inclined sides 14 at the first side 25 and the second side 26 respectively, without the holding top 4 protruding with respect to the lower face 27 and slides under a load 3 adjacent to the one to be gripped.

When this position has been reached, the horizontal actuator 37 moves the upper retention means 7 along the first sliding direction E so as to arrange the sheets 39 respectively at the first side 25, opposed the first side 25 attached to the first suction element 6, and at the second side 26, opposed the second side 26 attached to the second suction element 24.

In fact, given the nature of the load 3 taken into consideration for the present discussion, the gripper 1 is able to attach a first side 25 and a second side 26 in two different ways which correspond to a different arrangement of the other first side 25 and of the other second side 26.

Specifically, a first way of gripping the load 3 consists in attaching the first suction element 6 to a first side 25 and attaching the second suction element 24 to a second side 26; vice versa, a second way of gripping the load 3 consists in attaching the first suction element 6 to a second side 26 and attaching the second suction element 24 to a first side 25.

Consequently, depending on how the load 3 is gripped by the gripper 1, the upper retention means 7 are moved along the first sliding direction E.

After having arranged the sheets 39 respectively at a first side 25 and a second side 26, the second rotary actuator moves the upper retention means 7 along the third work direction D close to the load 3 without risking that the sheets 39 abut against the upper face 28.

In fact, having correctly arranged the lateral containment element 34, the sheets 39 slide vertically adjacent to the load 3, blocking the corresponding first side 25 and the corresponding second side 26 at the top, as shown in Figure 5.

In particular, the upper retention means 7 lower until pressing the upper suction element 33 against the upper face of the load 3.

In this way, the upper suction element 33 and the holding top 4 form a mechanism of the vice type and block the upper face 28 and the lower face 27 of the loads 3, respectively.

Moreover, the upper suction element 33 deforms to adapt to the protrusions 29 of the load 3 caused by the necks of the bottles so as to ensure a firm grip on the upper face 28 when pressed against the load 3.

In particular, in this position, the upper suction element 33 and holding top 4 operate in conjunction to retain the upper face 28 and the lower face 27 respectively, the first suction element 6 and the second suction element 24 retain at least partly a first side 25 and a second side 26 and the sheets 39 retain the other first side 25 and the other second side 26 at the necks of the bottles.

In this way, the lower face 27, the upper face 28 and each side 25, 26 of the load 3 are retained by the gripper 1 which firmly grasps the load 3.

Once the gripper 1 has gripped a load 3, the machine for the movement of loads 51 displaces the gripper 1, takes the load 3 from the pallet 8 (Figure 6) and arranges the holding top 4 resting on a target surface on which placing the load In this position, the upper retention means 7 lift up and free the upper face 28 of the load 3.

Subsequently, the holding top 4 slides from the projecting configuration to the retracted configuration and allows the lower face 27 of the load 3 to rest at least partly on the target surface.

When this position has been reached, the lateral suction means 5 are lowered until moving the load 3 to rest on the target surface.

Conveniently, the first suction element 6 and the second suction element 24 detach from the first side 25 and from the second side 26.

In this way, the load 3 is free from the grip of the gripper 1 which gripper can be moved by the machine for the movement of loads 51 in the proximity of another load 3 to be grasped.

It has in practice been found that the described invention achieves the intended objects.

In particular it is emphasized that the use of the lateral suction means allows the holding top to be positioned below the load without the latter being damaged. Moreover, the use of a substantially horizontal holding top on which resting the load allows significantly simplifying the grip of the loads with respect to known grippers.

Furthermore, the use of the lateral containment element allows retaining loads of various shapes and size and generally difficult to be grasped, such as e.g. bundles of plastic bottles.

Claims

1) Gripper (1) for the grip of loads, characterized by the fact that it comprises: at least one main frame (2) associable with a machine for the movement of loads (51);

an individual holding top (4) for holding at least one load (3), lying on a work top (A) substantially horizontal and associated with said main frame

(2) in a sliding manner along a first work direction (B) which is substantially horizontal in order to arrange itself below said load (3) so as to support it;

lateral suction means (5) provided with at least a first suction element (6) of said load (3), associated with said main frame (2) in a sliding manner along a second work direction (C) which is substantially vertical and adapted to lift at least one lateral portion of said load (3) in a lifting configuration in which said holding top can be inserted in a sliding manner below said load

(3);

upper retention means (7) of said load (3), associated with said main frame (2) in a sliding manner along a third work direction (D) which is substantially vertical and adapted to retain the top of said load (3) supported by said holding top (4).

2) Gripper (1) according to claim 1, characterized by the fact that said holding top (4) is sliding in a retractable manner between a projecting configuration, in which said holding top (4) extends overhanging from said main frame (2), and a retracted configuration, in which said holding top (4) is retracted adjacent to said main frame (2).

3) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said holding top (4) comprises at least one end portion (13) which is substantially pointed and has inclined sides (14) for guiding the insertion underneath said load (3).

4) Gripper (1) according to one or more of the preceding claims, characterized by the fact that it comprises at least one guide assembly (15, 16, 17) which is associated with said main frame (2), extends along said second work direction (C) and lies on top of said work top (A), said lateral suction means (5) being associated in a sliding manner with said guide assembly (15, 16, 17).

5) Gripper (1) according to one or more of the preceding claims, characterized by the fact that it comprises at least one guide unit (19, 20, 21) which is associated with said main frame (2), extends along said third work direction (D) and lies on top of said work top (A), said upper retention means (7) being associated in a sliding manner with said guide unit (19, 20, 21).

6) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said guide assembly (15, 16, 17) and said guide unit (19, 20, 21) are arranged substantially side by side.

7) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said first suction element (6) is moveable along a fourth horizontal work direction (G) to fasten to said load (3).

8) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said lateral suction means (5) comprise at least a second suction element (24) sliding along a fifth work direction (H) which is horizontal and substantially orthogonal to said fourth work direction (G), said load (3) comprising at least a first side (25) and at least a second side (26) substantially orthogonal to each other and said first suction element (6) and said second suction element (24) being able to fasten to said first side (25) and to said second side (26), respectively.

9) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said upper retention means (7) comprise at least one counteracting member (31) which projects overhanging from said guide unit (19, 20, 21) and has at least a lower portion (32) which can be placed in contact with the top of said load (3) and is adapted to press said load (3) against said holding top (4), by applying a predefined pressure value.

10) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said upper retention means (7) comprise at least one upper suction element (33) which can be fastened to the top of said load (3).

11) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said upper suction element (33) coincide with said lower portion (32) of said counteracting member (31).

12) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said upper suction element (33) is made of an elastically deformable material to adapt to the shape of said load (3) when pressed against said load (3).

13) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said upper retention means (7) comprise at least one lateral containment element (34) of said load (3).

14) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said lateral containment element (34) is associated with said counteracting member (31) in a sliding manner along a first sliding direction (E) which is substantially horizontal and orthogonal to said first work direction (B).

15) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said lateral containment element (34) is associated with said counteracting member (31) in a sliding manner along a second sliding direction (F) which is substantially vertical.

16) Gripper (1) according to one or more of the preceding claims, characterized by the fact that said lateral containment element (34) comprises at least two sheets (39) which are substantially vertical and arranged substantially orthogonal to each other.