FIELD OF THE INVENTION

The present invention relates to a device for feeding carton blanks to a packaging machine.

In particular, the proposed invention is advantageously used for picking up flat folded carton blanks from a stack, erecting them, that is making them assume a box- or case-like configuration, and subsequently feeding the box-like erected blanks to a packaging machine, so as to introduce products therein.

BACKGROUND OF THE INVENTION

Generally, the blanks are fed to a packaging machine, e.g. a boxing machine, by picking up devices having a rotating head, and suction means for stripping flat folded blanks from the bottom of a pile, and abutment means for erecting the blanks before their placing in relevant conveyor seats of the packaging machine. A rotating head device of this type includes substantially mechanisms, e.g. cam and/or epicyclical mechanisms, aimed at operating the above suction picking up means during the head rotation.

Examples of the above devices are described in the US Patent No. 4.194.442 and in the US Patent No. 6.503.108.

At present, known picking up devices try to correct the characteristic movement trajectories by applying suitable corrective devices to the moving device, which obviously results in very complicated and considerably bulky mechanisms.

Moreover, the above mentioned devices, described in the cited US Patents, pick up the flat surface of the blanks, which are later placed on the conveyors in a conveying station on an opposite flat surface, by turning the blanks by 180°.

Therefore, it is necessary to perform difficult adjustment operations of the device, when the height or dimension of the used blanks changes.

SUMMARY OF THE IMVENTION

The object of the present invention is to avoid the above mentioned disadvantages of the prior art .

The proposed invention is obtained by a device for feeding blanks to a packaging machine, including at least one rotating group for picking up flat folded carton blanks, by picking up means supported by the rotating group, from the bottom of a stack of carton blanks in picking up position, so as to erect them to form a box in a position corresponding to an erected condition, and then feeding them to an inlet station of said machine to place them one by one in the station in a placing position; the device being characterized in that said group includes, integrated with one another, at least one first cinematic series, which determines the movement of said picking up means along a closed path, extending between said picking up position and said placing position; and at least one second cinematic series, which controls and maintains constant the orientation of said picking up means .

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristic features of the invention are clearly understood from the contents of the claims, and the advantages will be better understood from the following detailed description, with reference to the enclosed figures, which show a preferred embodiment as a pure, not limiting example, in which:

Figure 1 is a schematic, front view of a preferred embodiment of a device for feeding carton blanks, according to the present invention; - Figure 2 is a detailed, section view, of a working group of the device of Figure 1, taken along the II- II and with some parts removed for sake of clarity;

Figures 3a to 3h show corresponding sequences of- positions of the operating group shown in Figure 2.

PREFERRED MODES OF CARRYING OUT THE INVENTION

With reference to Figures 1, 2 and 3a, the reference numeral 100 indicates a device for feeding carton blanks 99 to an inlet station 98 of a packaging machine M (of which the device 100 is an integral part) .

The inlet station 98 includes a pair 97 of conveyors 96, 96' with compartments 95.

The conveyors 96, 96' are arranged above one another and receive and feed the blanks 99, in their open configuration, defining a parallelepiped box or case A, toward subsequent work stations of the machine M (not shown) .

Advantageously, the inlet station 98 of the device 100, proposed by the present invention, defines a station R,

- A -

in which various products are introduced into the cases A, by known introducing means, not shown.

The device 100 includes at least one picking up group G, aimed at stripping flat folded blanks 99, one by one, from the bottom of a stack 94 of blanks 99, situated in a magazine 93, to erect them into a case A, and then to place them, one after another, in the compartments 95 of the pair 97 of conveyors 96, 96' of the station 98.

According to an embodiment, not shown, the device 100 includes preferably at least two picking up groups G, suitably arranged mutually, so as to further increase the picking up speed and rate, while maintaining the stresses on the mechanic parts of the whole device 100 and the picked up blanks 99 unvaried. As it has been better shown in Figure 2, the group G includes a rotating head and a framework 1, which carries, fastened thereto, cams 2 and a stationary wheel 3.

A rotor 4, acting as a satellite carrier for a horizontal axis 5, rotates on the framework 1, on a horizontal axis X, parallel to the axis 5, about which a lever 6 rotates.

A suction cup carrier 7 for the suction cups V is situated at the end of the lever 6, to grip the blanks 99 from the bottom of the stack 94, by the vacuum action. Consequently, the cams 2 , the axis 5 and the lever 6 define a first cinematic series Cl .

According to Figures from 3a to 3h, the lever 6 moves in a way determined by the combination of the rotation of the rotor 4 on the axis X and by the lever itself rotation on the axis 5, controlled by the cams 2.

The lever 6 movement defines a looped continuous motion path T (Figures from 3a to 3h) for the suction cup carrier 7, which, while running the same path T, moves without rotating, that is it maintains a constant horizontal orientation, due to the correction obtained by the link to the stationary wheel 3, created by a series of gears through a sleeve 10, thus defining a a second cinematic series C2.

The group G includes also a pair of rods or extensions 8, cooperating with the suction cup carrier 7 to erect the blanks 99.

Actually, the pair of extensions 8 is aimed at rotating on an axis Z, integral with the suction cup carrier 7.

This movement is obtained by operation of a cam 9, in turn set to rotate on an axis Y of the suction cup carrier 7, by the series of gears, which links it to the motionless wheel 3 via the sleeve 10.

The mechanism formed by cam 9 - wheel 3 - sleeve 10 - extensions 8, defines a third cinematic series C3. When in use, the picking up group G of the device 100 makes the suction cups V carrier 7 situate itself, with a movement in succession along the closed path T, under the stack 94 (Figure 3a - fixed picking up position P) , so as to strip a relevant flat folded blank 99; to begin the erection of the latter into a box-like A configuration by the extensions 8 ^' (Figures 3b and 3c - fixed erecting position K) , preferably rhomboid-shaping it, that is pushing the blank 99 against a suitable fixed abutment 92

(Figure 3d - fixed rhomboid-shaping position S) , to complete and maintain stable its open box-like A configuration, moving the group G along a portion Tl of the path T (Figures 3a, 3d and 3h) , substantially having

an elongated loop shape, to and from the abutment 92; and then to introduce and place the box A into a relevant compartment 95 of the pair 97 of conveyors 96, 96'

(Figures 3e and 3f - fixed introduction and placing position ID) , moving along a linear portion T2 of the path T (Figures 3e, 3f and 3h) , perfectly aligned with the upper run of the conveyor 96', before moving far from the station 98 (Figure 3g) and to begin the upward return motion along the path T, toward the stack 94 and then toward the picking up position P (Figure 3h) .

In particular, immediately downstream of the position ID, in which the box A is placed in the compartment 95 of the conveyor 96, 96', the group G performs a downward movement with respect to the conveyors 96, 96', defining a portion T3 of the path T, having substantially a shape of an elongated loop (Figures 3f, 3g and 3h) , so as to move rapidly away from the conveyors 96, 96', without any possibility of collision.

It is to be pointed out that the proposed device, with respect to the known devices having the same function, offers the possibility of correction of the characteristic path of an epicyclical mechanism

(cinematic series Cl) , of controlling the orientation of the suction cup carrier 7, which moves along the path T (cinematic series C2) , and of operating the extensions 8 on the suction cup carrier 7 independently from any other mechanism movement (cinematic series C3) .

In particular, the proposed device 100 can integrate the three cinematic series Cl, C2 and C3, thus making sufficient the presence of a single axis 5, protruding from the rotor 4, which results in a simple and compact structure.

Generally, the used mechanical scheme allows a considerable independence for defining the paths, which are most suitable to the scheme function and allows the boxes to be processed properly, due to the control of the inclination of the suction cup carrier and of the opening extensions rotation.

Actually, the fundamental characteristic feature of the device derives from the fact that it treats the blanks, aimed at becoming boxes, by picking them up, maintaining them and placing them, always on the same flat bottom surface, without any turning of the blanks, thus avoiding any adjustment of the device, when the height or dimension of the used blanks is changed.

Moreover, the inlet station 98 of the device 100 coincides with the station R of introduction of the products into the boxes A, as already said before, due to the fact that the above described structure allows best and most efficient placing of the blanks, already in their final, open box-like configuration, well defined and complete, which ensures a considerable and advantageous simplification of the machine M, as well as the reduction of the dimensions with respect to the known boxing machines, where the inlet stations can act only as units for transferring boxes to subsequent intermediate, completion stations .

Finally, it is to be pointed out that according to one variant of the present device, not shown, it is possible to mount the magazine 93 at an inclined orientation, determined in such a way, that, by suitably rotating the wheel 3, the suction cup carrier 7 picks up the blanks 99 from the stack 94, which is inclined at a selected angle.

Numerous changes and variants can be applied to the so conceived invention, without leaving the inventive scope thereof .

Further, all the technical detail can be substituted by technically equivalent elements .