ITFI20100119A1 - BATTERY-POWERED DEVICE FOR PAPER-BENDED PRODUCTS SUCH AS FOOTWEAR OR SIMILAR TO AN AUTOMATIC PACKAGING MACHINE - Google Patents

Description

DEVICE FOR FEEDING PAPER FOLDED PRODUCTS IN STACKS

SUCH AS HANDKERCHIEFS OR SIMILAR TO A PACKAGING MACHINE

AUTOMATIC

DESCRIPTION

The present invention relates to the packaging in stacks of articles folded in paper such as handkerchiefs, napkins and the like with a wrapping of sealable plastic film, by means of machines such as for example with rotating drum.

Known machines of this type include those described in US patents US4845924 and US5459979. In summary, these are high-speed packaging machines, including a drum equipped with radial pockets of adequate size for the product to be packaged, inside which the stacks of product to be packaged are inserted in rapid succession, with the simultaneous interposition of one plastic film segment, so as to carry out the complete wrapping of each pile, perfected by a sealing affixed to the film to obtain a closed packaging.

In machines of this type, due to the high operating speed that is required to ensure adequate productivity, it is very complex to compress the pile, maintain its correct geometry and insert it into the pockets of the drum without causing deformations or defects in the winding by the film. In particular, but not exclusively, it is difficult if not impossible to maintain a control of the position of the film and of the compression in the radial direction of insertion during the winding phase when the speed increases beyond a certain limit, causing defects in the package which, moreover, can also occur when the speed is kept below this limit.

The problem therefore arises of feeding stacks of compressible paper product into packaging machines such as those of the type just mentioned, overcoming the production limits currently imposed by the known art, maintaining the correct geometry of the assembly or stack of products, as well as the control compression (in the radial direction of insertion) and the position of the film in the winding phase, all with relatively simple and reliable construction solutions.

The device according to the present invention contributes to the resolution of this, the essential characteristics of which are defined by the first of the appended claims. The characteristics and advantages of the device according to the present invention will become clearer from the following description in an embodiment, provided by way of non-limiting example, with reference to the attached drawings in which:

- figure 1 is a schematic side view of a packaging machine with a device according to the invention, complete with all the other devices;

Figure 1a shows an enlargement of the area circumscribed by the circle I of Figure 1, with parts omitted for clarity of illustration;

- figure 2 is a schematic plan view of the machine of figure 1; - figure 3 is a schematic side view like that of figure 1 but limited to the devices for feeding, compressing, inserting the stacks and to the packaging drum;

- figure 4 and figure 5 are lateral and plan views respectively of an upper oscillating arm of the feeding device of the machine of the preceding figures;

figure 6 and figure 7 are lateral and plan views respectively of a lower oscillating arm of the feeding device of the machine of the preceding figures;

figure 8 is a cross-sectional view of the feeding device, with the upper and lower arms sectioned respectively according to the section lines A and B of figures 4 and 6;

Figure 9 schematically shows the movements of the upper oscillating arm of the feeding device in the various operating phases, in a side view;

- figure 10 and figure 11 are respectively schematic plan and front views of a device for inserting the film and extracting products;

Figures 12 and 13 are respectively a side view and a front view of a stop plate cooperating with the device of the two previous figures;

- figures 14, 15 and 16 are respectively a side view, a plan view and a front schematic view of the device for feeding the stacked products, with vertical inlet;

- figure 17 and figure 18 are a side view and a front view of a cylinder for feeding the stacks of products, belonging to the feeding device of the preceding figures;

- figure 19 is a schematic side view of the stack feeding device with horizontal product inlet;

- Figures 20a to 20g are side views of the packaging machine according to the invention in the various operating phases, from the insertion of a stack of product in the compression device to the exit of the packaged product.

With reference to said figures, and in particular to figures 1, 1a and 3, a packaging machine or apparatus according to the invention comprises a device 1 for inserting the product (stacks 3 of folded product to be packaged) into the feeding system, to which a pair of belts 2 coming from an upstream bending machine feed the product, in a direction orthogonal to the sheet according to the visualization of the figure.

A device indicated as a whole with 4 is responsible for feeding the batteries 3 to a compression device or system 8. The feeding takes place along a plane 35 inclined with respect to the horizontal, typically by about 10 °. Figure 3 shows in particular belts 50 for the pre-compression and feeding of the stacks 3 in the device 4, a pair of rollers 52 for returning the belts 50 adjustable in height according to the product to be packaged, and a stack 51 of pre-compressed products. during insertion into a downstream compression device 8.

There is also a device 5 for radial insertion of the stacks 3 into a packaging drum 21 equipped with pockets 58 of radially adjustable width according to the product to be packaged, an upper oscillating arm 6 for inserting the stacks into the drum 21, a lower oscillating arm 7 which slidably supports, along its own axis, the aforementioned stack compression device 8 comprising a lower compression plate 9 movable alternately in an orthogonal direction with respect to the axis of the arm 7. A front stop plate 10 of the piles 3 is in turn movable alternately along a direction orthogonal to that of the lower arm 7, when this is in the lower dead center position, in this case independently of the arm itself. A support 11 of the stop plate 10 is in fact constrained by means of a connection 34a to a base 34 of the machine (see Figure 2).

An upper actuation device 12 with multiple cams controls a first upper device with crank and connecting rod 13 for controlling the device 5 for inserting the batteries 3, that is, for moving the device 5 along the arm 6, a second upper device with crank and connecting rod 14 for the radial control of a movable portion of cam 22 designed, among other things, as will be understood, for the insertion of the plastic packaging film, and a third upper device with crank and connecting rod 15 for controlling the radial movement, i.e. ̈ along the arm 7 of the pile compression device 8.

A lower actuation device 16 with multiple cams controls a first lower device with crank and connecting rod 17 for controlling the lower compression plate 9 of the stacks 3, a second lower device with crank and connecting rod 18 for controlling the front stop plate 10 of the piles 3, a third lower device with crank and connecting rod 19 for controlling the rotation of the lower oscillating arm 7, a fourth lower device with crank and connecting rod 20 for controlling the rotation of the upper oscillating arm 6.

Both cam actuation devices therefore adopt a kinematics which provides an eccentrically rotating disc, which provides the cam surface, on which a crank hinged at one end enters tangential contact at an intermediate point, so that the crank is operated in oscillation, around the hinge point, due to the rotation of the disc. The connecting rods for the actuated devices are in turn hinged, as well as to the devices themselves, to the crank in points between the point of contact with the disc and the free end of the crank, all with geometries suitably established according to the displacements. , coordinated with each other, to be created.

The aforementioned movable portion of cam 22 serves to control extractors 24 which are also suitable for facilitating the insertion of the film in the pockets 58. More precisely, the movable portion 22 represents a radially displaceable end portion (as seen due to the effect of the second upper device 14 , of a fixed cam 23 which evolves in a ring around the axis of the drum on its side. In practice, the evolution of the fixed cam 23, according to the invention, is not closed-loop but open-loop, the opening being defined by a circumferential and radial (stepped) discontinuity in the film insertion area. The mobile portion 22 operates on this discontinuity, which moves radially between a radially external position (greater diameter of the guide cam) and a radially internal position (smaller diameter of the guide cam), correspondingly guiding the movement of the extractors. In an area 23a opposite the discontinuity the fixed cam 23 evolves then with continuity from the smaller and larger diameter so as to drive the extractors 24 between the radially backward position and the extracted position to extract the packaged stacks 3 from the pockets 58. The output of the packs from the drum 21 is indicated by the reference 25, again in figure 1.

Again in Figure 1 it is possible to identify a strip of film 29 fed continuously to package the product, fed by a cylinder 30 and cut into pieces by a cylinder 31 carrying a knife 32, and finally a transversal sealing system 39 for the wrapped film around the stacks 3.

With reference now in particular to Figure 2, a series of ducts 40 is formed in the drum 21 for the passage of the vacuum / suction exerted on the periphery of the drum itself. The ducts 40 are clearly visible and also indicated in Figure 3 and communicate with a fixed manifold 33 extending circumferentially for a certain arc, along which the sequential transmission of the depression must be obtained, drawn from an external vacuum source, for holding of the packaging film. Respective bearings 41 perform the function of transmitting motion to the extractors 24. A transmission shaft 42 connected to the drum 21 is driven by a motor 43 which also gives motion to a control axis 44 of the film feeding and cutting system. . The arms 6 and 7 are engaged idle on the shaft 42, one next to the other on one side of the drum and, as mentioned, the cam 23 constrained to the base 34. The same motor 43 also transmits the motion to a control axis 45 for the upper actuation device 12, to a control axis 46 for the lower actuation device 16, to a control axis 47 for the battery supply device 4, and finally to a control axis 48 for the device 1 battery insertion 3.

Returning to figure 3, various geometric elements of reference for the work of the machine are highlighted with the indices from 53 to 57, according to what will become clearer later on. A plane 54 defines the center line of the height 53 of the stacks fed by the device 4, thus resulting equidistant from the rollers 52, and at the same time the center line of the height or opening 56 of the compression device 8 in the phase of maximum opening, during the insertion phase of the product, at the lower dead center of the lower arm 7. A plane 55 also corresponds to the center line of the compression height in the phase of maximum compression and coincides with a diametrical plane of the drum 21. The compression height, indicated by 57, It is obviously adjustable according to the product to be packaged.

With particular reference to figures 4 to 8, the group of upper 6 and lower 7 oscillating arms is shown in greater detail with the device 5 for inserting the stacks, in the form of a bar projecting sideways towards the drum from a side of the upper arm 6 (arranged more externally), and the compression device 8 supported in cantilever fashion, again towards the drum, by the lower arm 7 (arranged more internally, ie adjacent to the drum itself). Obviously, the extension of the arms 6 and 7 is such that the devices 5 and 8 face the working surface of the drum, that is, the one in which the pockets are made.

Again in these figures, a connection 60 with the first upper device with crank and connecting rod 13, a connection 61 with the fourth device with crank and connecting rod 20 for controlling the upper oscillating arm 6, a connection 62 with the third upper device can be seen. crank and connecting rod 15 for controlling the pile compression device 8, a connection 63 with the third lower crank and connecting rod device 19 for controlling the lower swinging arm 7, an upper compression plate 64 adjustable according to the height of the pockets of the drum and of the stacks to be packaged, and finally a connection 65 with the first lower device with crank and connecting rod 17 for controlling the reciprocating motion of the lower compression plate 9.

The movement of the upper oscillating arm 6 in the various phases of operation is schematised in figure 9, together with the various positions correspondingly assumed by the insertion device 5. Figures 10 and 11 instead show more clearly an extractor 24, which performs, as also mentioned, to the function of assisting the insertion of the film, with its own bearing 41. These figures show a duct 71 and holes 72, open on the work surface, for the passage of the vacuum / suction, this surface being defined by a head 24a which represents the stop end against which the batteries stop. Figures 12 and 13 are instead isolated representations of the front stop plate 10 of the stacks 3, and it can be seen that it is in turn provided with holes 73 for the passage of the vacuum / suction.

Considering again in particular figures 1 and 3, on the drum 21 there is obtained a sequential valve 27 connected to the fixed cam 23 for the control of the depression on the side of insertion of the film, in the sense that in the feeding point of the film on the drum 21 by means of the cylinder 31, the aforesaid valve activates the suction by the extractors 24, removing it when the product is completely inserted, or at approximately 3/4 of the complete insertion stroke.

A further sequential valve 26 is materialized by a crown bound to the shaft 42 to which the drum 21 is integral, and it comes into operation at about 2/3 of the insertion phase, due to the movement of the extractors 24. This valve, by effect of the abutment, by the tail end of the extractors 24, on the bottom of the grooves defined by it, it removes the depression exerted by the extractors themselves, so before the insertion is completed, due to the depression applied at this point on the end flaps of the piece of film by only ducts 40 obtained on the surface of the drum, there is an effect of recalling the film towards the outside with a consequent effect of tight adhesion to the pile 3.

The valve 26, and in particular the bottom of the relative grooves, can have different diameters to control at which point of the insertion the depression is to be removed. A vacuum chamber 28 which transmits the suction to the extractors 24 is fed by a vacuum source normally with values of approximately double that applied to the manifold 33 precisely to ensure the safe positioning of the film during the insertion step.

With particular reference now to Figures 14 to 18, a vertical input feeding device 4 therefore comprises and also a series of stack conveyors 80 connected to a transmission system, a front stacks plate 81, a series of guides 82 of the stacks in the insertion phase, series of belts 83 and 87 external to the periphery of a conveyor cylinder 85 rotatable integrally to an axis 89, a series of cavities 84 obtained in the cylinder 85, a series of belts 86 inside the cylinder 85, and a plurality of drive and return rollers 88 for the various belts. The series of external belts, in each of which two or more belts evolve in parallel, therefore includes three successive series of external belts, namely belts 83 opposed to the belts 86 along the vertical or near vertical entry section, which compress the stacks to keep them in position and in phase, the belts 50 which transport the stacks along the outgoing section, and belts 87 in an intermediate deviation zone between the inlet and the outlet stretch, to keep the stacks in position in the passage from the vertical to the horizontal position, in adherence to the cylinder 85 from which they derive the motion.

In figure 19 an analogous feeding device with horizontal product inlet has, according to an alternative embodiment to the previous one, a simplified structure with a feeding cylinder 90 without cavities. In the case of horizontal exit of the stacks from the bending machine upstream, the cavities are not necessary as the wrapping angle of the belts is limited.

With reference now also and in particular to Figures 20a to 20g, the machine according to the invention operates in the following way.

As said, the machine can be arranged for a vertical or horizontal feeding, and in any case for a good functioning the insertion plane 35 must have a certain inclination with respect to the horizontal, descending towards the drum 21 and preferably equal to about 10 ° . In this way, the piles 3 adhere, as will be seen better shortly, to the front stop plate, resulting perfectly perpendicular to the plane defined by the lower compression plate 9.

Starting from the phase referred to in Figures 1, 14 and 20a, the product stacks 3 are fed by the belts 2, and at the end of the path they are inserted into the product guides 82 adhering to the stop plate 81. The insertion feet 80 have a continuous vertical and horizontal movement at a constant speed equal to that of the belts 83 and 86 driven by the cylinder 85 of the feeding device 4, belts which actually receive the stack by operating on opposite ends of it and also carrying out a slight pre-compression. The advancing stacks reach the cavities 84 obtained in the cylinder 85, and after detachment from the belts 83 they are kept compressed towards the cylinder 85 through the further external belts 87 which receive the motion from the cylinder itself by friction with the surface thereof. In this way the correct peripheral speed is maintained without causing deformation of the stacks themselves.

At the exit of the stacks from the cylinder 85, the belts 50 in cooperation with the internal belts 86 transport the stacks until they are inserted into the compression device 8. The output rollers 52 of the belts 50 and 86 have, as said, an adjustment system to maintain a position equidistant with respect to the center plane 54 according to the height of the product to be packaged. The speed of the belts varies according to the diameter of the cylinder 85 and the number of cavities 84 present in the cylinder itself. The stacks coming out of the belts 50, 86 have a compressed height approximately equal to that of the packaged package, and are inserted into the compression device 8 in its phase of maximum opening 56 at the lower dead point of the arm 7. This height 56 It is normally 50% greater than the height of the stacks at the exit of the belts 50, 86.

When it is inserted into the compression device (figure 20b) the stack expands and adheres to the stop plate 10 which exerts a suction action (holes 73) which ensures perfect alignment to the plate itself even of the single folded sheets of paper , before compression.

Figure 20c represents the beginning of the compression phase. The arm 7 begins its upward movement, with the compression plate 9 which, having an orthogonal movement relative to the arm 7, reaches the programmed height and compresses the stack in cooperation with the upper plate 64. This programmed height obviously coincides with the height of the pockets 58 of the packaging drum 21 and is maintained until the stack is completely inserted into the drum itself.

The front stop plate 10, in turn equipped with a movement which is orthogonal to the lower arm 7 in the lower end stroke position, in the meantime reaches its own lower end stroke position and maintains it. At this point the compression device constrained to the arm 7 in the condition of maximum compression of the stack carries out a radial movement along the axis of the arm itself until it reaches the vicinity of the drum 21

The upper arm 6 has in the meantime established and continued a descent phase, constrained to the axis of the drum 21, until it reaches the lower dead center, to then reverse the motion and start an ascending phase.

Turning to figure 20d, the arms 6 and 7 have reached an alignment position suitable to allow the insertion of the stack in a pocket 58 of the drum 21, and at this point the insertion device 5, with a radial movement, advances up to to find on the stack of compressed product. Reached the position in which the distance from the periphery of the drum corresponds to the width of the stack, the movable cam portion 22 also begins a radial backward movement, accompanying the product in a coordinated way with the device 5, so as to keep it neatly controlled on two opposite sides, until completely inserted.

Figure 20e shows the insertion phase of the stack 3 with the arms 6 and 7 which rotate in phase with each other and with one of the pockets 58 of the drum 21. The device 5 advances until the stack 3 is completely inserted, adhering to the which, by means of the ducts 40 connected to a source of depression, a piece of film had previously been interposed so as to carry out the winding, in accordance with what traditionally takes place but with some unprecedented expedients which will be mentioned later. The front stop plate 10 returns to the starting condition.

Moving on to figure 20f, the upper arm 6 continues to rise towards the top dead center, the insertion device 5 maintains its position of closest approach to the drum 21, and the upper arm 7 reaches its top dead center. The compression device 8 carries out an abrupt radial movement away until it returns to the starting position, so as to free the space between the upper compression plate 64 of the device 8 and the insertion device 5.

Finally, as can be seen in Figure 20g, the arm 7 and the compression plate 9 perform a return movement to the starting position to receive a new stack of product. The upper arm 6 reaches the top dead center and reverses the movement, while the insertion device begins its radial movement along the arm 6 to return to the starting position, without interfering as said with the upper compression plate 64 which, constrained to the device 8, is already in position for receiving a new stack 3. The drum 21 continues its rotation at constant speed, clockwise according to the representation of the figures, and a new packaging pocket 58 advances to the phase point with arms 6, 7. The system is ready for a new cycle.

Returning to follow the path of the stacks inside the drum 21, it will be noted how the control of the stacks, with the film wrapped inside the pockets, is also taken over by the extractors 24 which, due to the movement of the portion of the cam 22 in the insertion, retract providing an accompanying feedback to the piles themselves in the insertion movement, on the internal side.

Furthermore, the suction action exerted by the same extractors 24 helps to keep the stack and the wrapping of the film in order. Passing in correspondence with the welding system 39, the packet is welded and then expelled thanks to the output of its own extractor controlled by the evolution 23a of the cam 23 in the region diametrically opposite to that of insertion. The suction / depression control exerted by the extractors 24 is synchronized along the due arc of rotation of the drum by means of the valves 26 and 27.

The advantages summed up by the present invention are manifold. The feeding system by means of belts, which can have variable speed according to the diameter of the cylinder, ensures a high feeding speed while maintaining the control in phase of the position of the product, with reduced insertion time of the stacks in the compression device, compared to to a chain system, due to its ability not to lead to product slowdowns. Furthermore, there is the possibility of vertical or horizontal feeding of the stacks, with pre-compression of the stacks before insertion into the actual compression device so as to limit the range of movement of the arms 6 and 7, and consequent construction simplicity. .

The stop plate of the stack, bound to the base, with its own vacuum system, to perfectly align the stack itself, is in turn able to ensure a significant improvement in the insertion operations, for speed, precision and construction optimization. More generally, these results are the effect of the entire conception (structure and kinematics) of the compression and insertion system, with - among other things - precise control of the axial compression of the stack by means of the insertion device 5, in cooperation with the extractor 24 and the movable cam portion 22. The extractor that accompanies the insertion of the stack into the pocket with precise control of the position of the film, through connection to the vacuum source, generally represents an unprecedented and extremely advantageous feature in relationship to the quality requirements of the packaging.

The vertical / horizontal spatial references used above are evidently in relation to the most typical operating configuration, and to the orientation represented in the figures, but it is clear that they must not assume any limiting connotation.

The present invention has been described heretofore with reference to its preferred embodiments. It is to be understood that other embodiments may exist which pertain to the same inventive nucleus, all falling within the scope of the protection of the claims set forth below.

Claims (8)

CLAIMS 1. A device for feeding a succession of stacks of products folded into paper such as handkerchiefs and the like, in a direction of transport towards means of compression and insertion of the stacks in a packaging system with pieces of plastic film, characterized in that it comprises first and second belt transport means adapted to operate respectively on opposite ends of each of said stacks by exerting a prestressing action on them in a direction orthogonal to said transport direction. The device according to claim 1, wherein said first and second belt transport means are arranged in such a way as to provide an outfeed direction inclined with respect to the horizontal, with a descending inclination towards said compression and insertion means, preferably equal to about 10 °. The device according to claim 1 or 2, wherein said first and second belt means comprise at least one internal belt and at least one external belt which wind at a common output end around respective rollers, at least one of which It is designed to be moved towards and away from the other roller to adjust the degree of prestressing of said output stacks. The device according to claim 3, wherein said first and second belt means respectively comprise at least one inner belt which winds around the periphery of a motorized conveyor cylinder, and at least one outer belt spaced radially from said inner belt. 5. The device according to claim 4, comprising a series of internal belts which evolve in parallel around said conveyor cylinder with a first inlet section, ascending vertically or close to the vertical, and a second section, outfeed according to the direction of outfeed, horizontal or with a descending inclination, cavities being formed in said conveyor cylinder are suitable for accommodating at least partially said stacks in order to facilitate their transport between said inlet section and said outlet section. 6. The device according to claim 5, comprising three series of external belts which, in each series, evolve in parallel, respectively along said inlet section, along said outlet section, and in an intermediate deviation zone between said inlet section and said outlet portion, at least the series of external belts in the intermediate zone receiving the transport motion by friction on the part of said cylinder. 7. The device according to claim 5 or 6, comprising or associated with conveyor means arranged upstream and below said inlet section, feeding said batteries to be fed, comprising guide and stop means for the batteries to guide their insertion into said entrance section. The device according to any one of the preceding claims, comprising or associated with means for adjusting the speed of said belt transport means.