EP0733548A1

EP0733548A1 - Apparatus for packaging various products, particularly confectionery products having various shapes

Info

Publication number: EP0733548A1
Application number: EP95830105A
Authority: EP
Inventors: Cesare Tartarini
Original assignee: NUOVA FIMA IMBALLAGGI Srl
Current assignee: NUOVA FIMA IMBALLAGGI Srl
Priority date: 1995-03-22
Filing date: 1995-03-22
Publication date: 1996-09-25

Abstract

The apparatus allows to package confectionery products having various shapes. The apparatus comprises a first rotating unit (24) provided with clamps (26) that grip each product with the wrapping arranged thereon and transfer it to the clamps (48) of a second rotating unit (46). The units are actuated intermittently. During rotation and during the pauses in rotation, appropriately provided fixed and movable folding elements arranged along the path of the clamps (26) of the first unit (24) partially fold the wrapping onto the product, while additional fixed and movable folding elements arranged along the path of the clamps (48) of the second unit (46) close the wrapping around the product. The shape of the folding elements and their arrangement are chosen according to the type of package.

Description

The present invention relates to an apparatus for packaging various products. The invention is aimed particularly but not exclusively at the packaging of confectionery products having various shapes, such as chocolates, nougats, candies, and the like.
Such currently commercially available confectionery products are enclosed in a wrapping the packaging method whereof is chosen according to the geometric characteristics of the products themselves. Thus, for example, some kinds of chocolates are packaged with a so-called sleeve or fancy wrapping, whereas a so-called bunch wrapping is preferred for chocolates shaped like a truncated cone, such as those commercially known by the trademarks "Bacio" or "Boero". A sleeve wrapping with a single twist or with two twists is often used for products such as nougats.
It is evident that the production of such a variety of wrappings requires a corresponding variety of apparatuses, one for each kind of wrapping. The packaging machine industry has so far failed to provide producers with an apparatus that can be modified with simple operations in order to handle the various kinds of wrapping, also taking into account that the wrapping often comprises a plurality of superimposed sheets.
The technical aim of the present invention is indeed to provide an apparatus that is versatile in use, that is to say, that can be modified so as to be preset according to the desired type of package.
Within the scope of this aim, an object of the present invention is to provide an apparatus that can be modified with simple operations even by personnel that does not have a particular mechanical specialization.
Another object of the present invention is to provide an apparatus that is structurally simple, reliable in operation, and fully equivalent, in terms of efficiency, to the dedicated machines currently in use.
This aim and these objects are achieved by an apparatus for packaging various products, particularly confectionery products having various shapes, in a wrapping comprising at least one sheet, said apparatus being characterized in that it comprises a product conveyor for feeding individual products to be packaged; a feeder of said sheet, provided with means for positioning said sheet on a product; a first unit and a second unit that rotate about parallel and horizontal axes, each unit supporting a plurality of clamps angularly equidistant and provided with jaws having a tangential grip line; said units being actuated with an intermittent motion and with angular strokes that are equal to the angular distance between said clamps; said units being mutually synchronized so that when they are in the stop position a first clamp of a first unit is in the position for gripping said sheet and said product and a second clamp of the same unit is in an angular position wherein its grip line is at right angles to the grip line of a clamp of the other unit; said clamps being actuated, during the stops in the rotation of the units, so that while said first clamp grips the product and the sheet, said second clamp opens to release the product and the sheet to a clamp of the second unit, the grip line whereof lies at right angles to the grip line of said second clamp of the first unit; said apparatus being furthermore characterized in that it comprises stationary folding devices that act on the sheet during the rotation of the units and cooperate with movable folding devices that act on the sheet during the stops in the rotation of the units; said folding devices being arranged along the path followed by said clamps and being adapted to complete the folding of the sheet around the product; means being furthermore provided for receiving and transferring the packaged product onto a removal element.
Further characteristics and advantages of the present invention will become apparent from the following description of the apparatus in its embodiments for producing five different types of wrapping.
In the accompanying drawings:

figures 1 to 9 are views of the various steps for forming a so-called sleeve-type wrapping;
figures 10 to 16 are views of the steps for forming a so-called fancy-type wrapping;
figures 17 to 25 are views of the steps for forming a so-called single twist wrapping;
figures 26 to 31 are views of the steps for forming a so-called bunch wrapping;
figures 32 and 33 are, respectively, a lateral elevation view and a front elevation view of an apparatus for packaging products with a sleeve wrapping, figure 32 being taken along the plane XXXII-XXXII of figure 33 and figure 33 being taken along the plane XXXIII-XXXIII of figure 32;
figure 34 is a sectional view, taken substantially along the plane XXXIV-XXXIV of figure 32;
figure 35 is an enlarged-scale view of the central region of figure 32;
figures 36 and 37 are respectively a lateral elevation view and a front elevation view of an apparatus for packaging products with a fancy wrapping;
figure 38 is a perspective view of a detail of the apparatus of figures 36 and 37;
figures 39 and 40 are respectively a lateral elevation view and a front elevation view of an apparatus for packaging products with a single-twist wrapping;
figures 41 and 42 are respectively a lateral elevation view and a front elevation view of an apparatus for packaging products with a double-twist wrapping;
figures 43 and 44 are respectively a lateral elevation view and a front elevation view of an apparatus for packaging products with a bunch wrapping;
figure 45 is a sectional view, taken along the plane XLV-XLV of figure 43;
figure 46 is a view of the initial step for forming a wrapping for a product of the so-called Boero type (chocolate-coated cherry);
figure 47 is a view of a packaged Boero;
figure 48 is a side view of a detail of the entry of the product into the apparatus for forming a Boero; and finally
figure 49 is a front view of the detail of figure 48. With reference to the above figures 1 to 9, first of all the type of product to be packaged and the wrapping used to package it are defined for greater clarity in explanation. The product is constituted by a chocolate, nougat, or other confectionery product, generally designated by the reference numeral 1, which is substantially shaped like a slightly tapering rectangular prism with a top face 2, a bottom face or base 3, two side faces 4 and 5 (hereinafter referenced as ends), and two longitudinal faces 6 and 7. Hereinafter, the term "product" also references to the unit composed of the actual product and its wrapping.

The wrapping comprises two rectangular sheets 8 and 9 having the same area; the first one 8 is made of tinfoil, aluminum coupled to paper, or the like, and remains in contact with the outer surface of the product, whereas the second sheet 9 acts as external covering and is made of heat-sealable material. The operations for folding the sheets 8 and 9 to form the wrapping are performed with the apparatus shown in figures 32 to 35, and entail first of all the positioning of the inner sheet 8 on the top face 2 and the subsequent U-shaped folding of the sheet so as to form two flaps 10 and 11 that adhere to the longitudinal faces 6 and 7 (see figure 2). Then the regions 12 and 13 of the sheet 8 are folded onto the ends 4 and 5 so that two pairs of wings 14, 15 and 16, 17 form at the opposite ends of the product (see figure 2).
Before wrapping the sheet 8 fully around the product, the second sheet 9 of the wrapping is placed (see figure 3) onto the central region 17a of the sheet 8 that covers the top face 2 of the product. Then the operations for folding the sheet 9 onto the ends 4 and 5 are repeated, so as to obtain a wrapping comprising the coupled sheets 8 and 9. Since said wrapping, as shown in figure 4, has the same appearance as that shown in figure 2, the same reference numerals are used to designate the various regions or flaps for the sake of simplicity in description and to avoid useless repetitions.
During the subsequent steps, first of all the wings 14 and 17 are folded against the ends 4 and 5 (see figures 5 and 6) and then folded onto the base 3 of the product, producing the configuration of figure 7.
At this point, the product is completely enclosed by folding the flaps 10 and 11 onto the base 3 and by joining them by heat-contact welding or the like (see figures 8 and 9). It should be noted that in order to mutually join the overlapping flaps 10 and 11, the end of the sheet 9 must protrude from the end of the underlying sheet 8, so that in the region where the flaps mutually overlap the sheet 9 of the outer flap 11 can make contact with the sheet 9 of the inner flap 10, so as to seal the package by heat-welding the wrapping.
The apparatus preset for forming the package of figures 1 to 9 comprises (see figure 34) a product feeding conveyor 18, constituted by a belt, the upper segment whereof moves in the direction A. At the end portion of the belt 18 the products are gripped by a clamp 19 moving in a reciprocating manner in the same direction A and are moved positively below a surface 20, the tinfoil sheet 8 being placed thereabove.
The sheet 8 is cut, by means of a pair of contrarotating blades 21, from a tape N fed by a feeder 22. The tape N is unwound in the direction B, at right angles to A, from a reel (not shown) by means of a first pair of contrarotating rollers 22a and is driven onto the surface 20 by a second pair of contrarotating rollers 22b, connected to the rollers 22a by means of a transmission belt 22c. The rollers 22a and 22b and the blades 21 are supported within shoulders 22d mounted so as to cantilever out of the frame 22e of the apparatus, and their actuation is produced by a drive unit accommodated in the frame but not shown since it is fully conventional. The surface 20 is provided with an opening 23 aligned with the belt 18, and the mutual arrangement of the belt 18 and the surface 20 is such that the upper face of the product gripped by the clamp 19 is substantially co-planar with respect to the surface 20. The strokes of the clamp 19 are such that the product removed from the feeder belt 18 is transferred at the opening 23 beneath the sheet 8, so as to allow to pick it up it together with the sheet and to transfer it through folding devices by means of a unit generally designated by the reference numeral 24.
The unit 24 comprises (see figure 35) a drum 25 that is rotationally rigidly coupled to a shaft 25a that is accommodated inside the support and cantilevers horizontally out of the frame 22e of the apparatus. The drum 25 is provided, at the front, in its peripheral region, with a plurality of clamps 26 (six clamps 26, mutually offset by 60^o, are provided in the example); each clamp comprises two articulated arms 27 and 28 extending radially and supporting, at their ends, respective jaws 29 and 30 that give the arms an L-shaped configuration.
The arms 27 and 28 are supported so that their plane of oscillation is at right angles to the rotation axis of the drum. The drum 25 rotates intermittently in the direction C, so that each clamp 26 assumes, in succession, the angular positions I to VI. The jaws 29 and 30 of the clamps 26 are tangentially mutually opposite, and their opposite surfaces are smaller than the surfaces of the opposite faces 2 and 3 of the products to be packaged. The length of the arms is such that, during the rotation of the drum 25, the jaws 29 and 30 can pass through the opening 23 without interfering with the clamp 19.
The rotation of the drum 25 and the actuation of the clamps 26 are performed by kinematic systems that are not shown, are arranged inside the frame 22e, and are fully conventional in the field of packaging machines. In particular, as regards the actuation of the clamps 26, inside the drum 25 there are cam means activated when the drum is not moving. In this stopped position, a clamp 26 is in the position I for gripping the product fed by the belt 18 and located at the opening 23.
When the drum is not moving, the next clamp 26 along the direction C is in the position II, at a device 31 for feeding the second sheets 9. The structure of said second feeder 31 is fully identical to the structure of the feeder 22 of the sheets 8. Said second feeder too, in fact, comprises two contrarotating blades 32 and two pairs of contrarotating rollers 33a and 33b that move the sheet 9, cut from the tape M, onto a surface 34 that has an opening 35 allowing the jaws 29 and 30 of the clamps 26 to pass. Upstream of the surface 34 there is a folding station 35a comprising first stationary folding devices for folding the wings 14 and 17 of the sheets 8. Said folding devices are constituted by two parallel sectors 36, which are curved concentrically with respect to the rotation axis of the drum 25, and by two laminae 37 and 38, which converge in the direction C towards the opening 35. The sectors 36, only one of which is shown in figures 32 to 35 (it being implied that the other one lies above the plane of the drawing), are fixed to respective brackets 39 supported by the stationary frame and their mutual distance is equal to the length of the chocolate, that is to say, to the distance between the ends 4 and 5. The laminae 37 and 38 lie at right angles to the sectors 36 and are fixed to the brackets 39 so that in practice the laminae 37 and 38 and the sectors 36 form a sort of funnel, the jaws 29 and 30 passing therethrough. In order to allow the arms 27 and 28 of the clamps to pass during the rotation of the drum, the internal lamina 37 has a slit in the rotation plane. Whereas the inner lamina 37 is connected to the surface 34 with one end, the outer lamina 38 forms, together with the surface 34, a gap 39, a roller 40 engaging therein; said roller is mounted at the end of an arm of a rocker 41, on the other arm whereof a spring 42 acts. The purpose of the roller 40 is to momentarily retain the product when, in order to allow the positioning of the second sheet 9, it is necessary to momentarily open the respective clamp 26.
An additional folding station 42a is arranged downstream of the first stationary folding elements 36, 37, and 38 and is offset by the same angle formed between the clamps 26; said folding station comprises second stationary folding elements fully identical to the first ones, except for the absence of a rocker similar to the rocker 41. Said second folding elements have the purpose of folding the second sheet 9 over the first sheet 8, and comprise two curved sectors 43 and two converging laminae 44 and 45 that act so as to form a wrapping that is folded as shown in figure 4.
Once said wrapping has been completed, the product is transferred onto a second unit 46 that comprises a drum 47 supported by a shaft located inside the sleeve 47a, which is supported by the frame 22e in a cantilevered manner. The drum 47, which is not shown in figure 32, can rotate intermittently in the direction D.
Like the unit 24, the unit 46, too, comprises six clamps 48 mutually offset by 60^o; each one sequentially assumes the positions I' to VI' during the intermittent rotation of the drum 47. Each clamp 48 is constituted by two arms 49 and 50 that end with respective jaws 51 and 52, and are mounted in a cantilevered manner on the side of the drum 47 that is directed towards the frame, that is to say, on the side that lies opposite to the one from which the clamps 26 protrude. The intermittent rotation of the unit 46 is synchronized with the rotation of the unit 24, so as to allow the clamp 26 that is in the position III to cooperate with a corresponding clamp 48 that is in the position I'. In these positions III and I', the line of operation of the clamp 48 is at right angles to the line of operation of the clamp 26, so that the jaws 51 and 52 can grip the product on the longitudinal faces 6 and 7 before the clamps 26 are opened. In this manner, the products can pass from the clamps 26 to the clamps 48, which transfer them towards additional folding devices adapted to complete the closure of the wrapping.
Said additional folding devices comprise a fork (see figure 33) to the tines whereof respective movable folding elements 53 and 54 and two fixed folding elements 55 and 56 are rigidly coupled. The folding elements 53 and 54 are actuated reciprocatingly and tangentially with respect to the drum 47 by means of a lever system forming an articulated parallelogram. During the stroke in the direction D, these folding devices fold the wings 14 and 16 against the ends 4 and 5 of the product. The fixed folding elements 55 and 56 are constituted by two shoulders that are concentric with respect to the drum 47 and have front edges that fold the wings 15 and 17 above the wings 14 and 16 during the rotation of the drum. The shoulders 55 and 56 keep the wings 14-17 against the ends 4 and 5 of the product until the clamps 48 reach the position II'.
The lever system shaped like an articulated parallelogram comprises a shaft 57 oscillatably actuated by a drive unit that lies inside the frame (not shown in the drawing), a crank 58 being keyed thereon; the arm 59 for coupling the fork of the folding elements 53 and 54 is pivoted to the end of said crank.
The arm 59 is orientated tangentially with respect to the drum 47, and its end that lies opposite to the folding elements 53 and 54 is articulately connected, by means of a link 60, to an arm 61 that is rigidly coupled to the support of the shaft 57 and is therefore stationary. Accordingly, the oscillating movement of the crank 58, produced by the alternating rotation of the shaft 57, leads to a back-and-forth movement of the folding elements 53 and 54; this movement is corrected by the link 60 and occurs tangentially with respect to the drum 47, allowing the folding elements 53 and 54 to act on the flaps 14 and 16 of the wrapping and to fold them on the ends 4 and 5.
When the product 1 moves along the channel formed between the fixed shoulders 55 and 56, the shape of the wrapping is the one shown in figure 6. The elements for completing the folding action are provided at the exit of the channel. Said elements comprise two movable folding elements having levers 62 and 63, which are actuated in opposition and are articulately supported in a head 64 mounted on the frame 22e, so as to oscillate on a radial plane passing through the rotation axis of the drum 47.
The levers 62 and 63 are provided with folding plates 62a and 63a which, during the approach of the levers 62 and 63, act laterally on the wings 14-17 (more specifically, on the portions of the wings 14-17 protruding from the base 3), folding the wings 14 and 15 of the wrapping on one side and the wings 16 and 17 on the other side onto the base 3 of the product and producing the configuration shown in figure 7. As soon as the levers 62 and 63 have moved apart again, an additional movable folding element 65 is activated; said folding element is fixed to the end of a lever 66 supported in said head 64 and is curved along a circumference that is tangent to the base 3 of the product. The lever 66 oscillates on a plane that is co-planar with respect to the drum 47, so as to act on the rear flap 10 and overturn it onto the previously folded wings 14-17 (figure 8).
Before the folding element 65 moves backwards again, the drum 47 is activated in the direction D and the product is transferred beneath a fixed folding element 67 constituted by a cylindrical wall that is concentric with respect to the drum. The abutment of the front flap 11 against the rear edge of the folding element 67 causes the flap 11 to fold backwards onto the flap 10, thus completing the closure of the wrapping around the product (figure 9). It should be noted that the movable folding elements 53, 54, 62, 63 and 65 are actuated synchronously during the pauses in the rotation of the drums 25 and 47.
Figures 32 and 33 illustrate an additional movable shoulder 67a supported by an arm 67b that is articulated coaxially to, but is shorter than, the folding element 65. The purpose of said additional shoulder 67a is to keep the flap 10 in a vertical position during the operation of the plates 62a, 63a of the movable folding elements, while the flap 9 is supported by the front edge of the fixed folding element 67. The folding element 65 is appropriately chamfered so as to start folding the flap 10 before the plates 62a and 63a have fully left their position for folding the wings 14-17, on the base 3, in order to achieve perfect overturning of the flap 10 onto the base 3.
The fixed folding element 67 keeps the wrapping closed until sealing is performed; said sealing consists in providing two spot-welds that join the overlapping flaps 10 and 11 of the outer sheet 9. It should be noted that as mentioned earlier, the flap 11 of the outer sheet 9 protrudes from the inner sheet 8 to allow contact between heat-weldable materials.
Welding is performed by means of two welding elements 68 and 69 oscillatably mounted on the frame 22e with the same angular spacing as the clamps 48 in the positions III' and IV'. Each welding element comprises an oscillating arm 70 and 71 ending with a welding body 72 and 73. The welders 68 and 69 are actuated by appropriate kinematic systems so as to oscillate on a vertical plane that is co-planar with respect to the plane of the drum 47, so as to act, with the respective welding bodies 72 and 73, through slots of the fixed folding element 67, on the flap 11 to join it to the underlying flap 10.
The fixed folding element 67 lies concentrically with respect to the drum 47 from the top thereof, that is to say, from the position II', to the diametrically opposite position V' at which the clamps 47 release the product, which is now packaged, towards receiving and removal elements.
In the embodiment of figures 32 to 35, the receiving elements are constituted by two walls 74 and 75 (see figure 33 in particular) articulated, along one edge, to an L-shaped element 76 that is fixed onto the footing of the frame 22e; said walls are mutually drawn by a traction spring 77. The walls 74 and 75, by virtue of the spring 77, can grip the packaged product when the clamp 48 that retained it opens when it reaches the position V'. The distance between the walls 74 and 75 is of course less than the length of the products, so that when a clamp 48 reaches the lower position V' the product retained thereby moves between the walls 74 and 75 and continues to be retained even when the clamp 48 opens.
The product that remains gripped between the walls 74 and 75 is then transferred onto a removal conveyor, which is constituted by a belt 78 the upper segment whereof moves in the direction E and is arranged, with respect to the lower edge of the walls 74 and 75, at a distance greater than the size of the products.
The transfer of the product onto the belt 78 is actuated positively by a pusher 79 actuated vertically with a back-and-forth motion and acting on the product by pushing it downwards, so that when the pusher 79 has moved down to the lower edge of the walls 74 and 75 the product is loose and can be deposited onto the belt 78.
The pusher 79 is fixed to the upper end of a strip 80 that is part of an articulated parallelogram comprising an oscillating crank 81 and a link 82 that articulately connects a median point of the strip 80 to a support of the footing. Essentially, the parallelogram 80-81, as described above for the parallelogram 58-60, allows to achieve a practically linear vertical movement of the pusher 79, by virtue whereof the product is pushed between the walls 74 and 75.
In order to prevent the difference in speed from causing incorrect positioning of the product and variations in its distance with respect to the products preceding it along the belt (which might compromise subsequent steps for packaging the products in a container) when the product makes contact with the belt 78, there is provided a spacer device consisting of an articulated parallelogram of the type previously designated by the reference numerals 80-82 and comprising a crank 83, a link 84, and a strip 85 that supports a pusher 86. The parallelogram 84-85 is orientated so that the pusher 86 moves linearly on the belt 78 in the direction E from a position upstream of the point where the products descend from the walls 74 and 75 until said pusher reaches the same speed as the belt 78. In this manner, the products carried by the belt maintain a correct position and their mutual distance is substantially constant since it is determined by the frequency of the pusher 86.
The operation of the described apparatus can be summarized as follows. Once the products 1 fed by the belt 18 have reached the end portion of said belt, they are individually gripped by the clamp 19 and placed beneath the opening 23 of the surface 20, a sheet 8 having been placed thereon in the meantime. The product facing the opening 23 is interposed between the jaws 29 and 30 of the clamp 27 (which is waiting in the position I), so that by closing the clamp 26 the product and the sheet 8 arranged thereon are locked between the jaws 29 and 30; the plane lying between the jaw 30 and the region 17a of the product forms the grip plane for the sheet 8. At this point the drum 25 is made to turn through a 60^o step; during this rotation, the sheet 8 is folded so as to assume the configuration of figure 2 by virtue of the action of the folding elements 36-38. Once the rotation through 60^o has been completed, the product 87 (this reference numeral designating, hereinafter, the composite item comprising the actual product and the wrapping) is in the position II, at the opening 35 of the surface 34, for the application of the second sheet 9. However, in order to apply the second sheet 9 onto the first sheet 8 it is necessary to momentarily open the clamp 26, moving away the jaw 30 that rests on the upper face of the product. The opening of the jaw 30 thus allows the rollers 33a to insert and position the sheet 9 onto the sheet 8, then the clamp 26 is closed again and the drum 25 performs an additional rotation through 60^o towards the position III, moving the clamp 26 into the position for transferring the product onto the second unit 46 and exactly between the open jaws 51 and 52 of one of the six clamps 48 mounted on the drum 47 and standing by in the position I'. During this rotation from the position II to the position III, the sheet 9 is folded like the sheet 8 by the folding elements 43-45 and therefore the wrapping has the configuration shown in figure 4.
Before the drum 47 performs an additional rotation, the tangential folding elements 53 and 54 fold the wings 14 and 16 against the ends 4 and 5 of the product, so that when the drum 47 turns through 60^o from the position I' to the position II' and the product 87 enters the channel formed by the fixed shoulders 55 and 56, the wings 15 and 17 abut against the front edges of the shoulders and are folded over the wings 14 and 16, producing the configuration shown in figure 6.
The rotation of the drum 47 moves the clamp 48, which holds the product with its wrapping still partially open, in the top position II' to fold the wings 14-17 onto the base 3 of the product by means of a mutual approach of the levers 62 and 63, so that the wrapping assumes the configuration shown in figure 7. Before the levers 62 and 63 swing towards the product, the shoulder 67a moves adjacent to the flap 10, so as to prevent said flap from folding incorrectly during the operation of the plates 62a and 62b to fold the flaps 15-17. As soon as the levers 62 and 63 have been moved mutually apart again, the folding element 65 is activated and folds the flap 10 onto the previously folded wings 14-17.
The folding element 65 maintains its position on the product until the drum 47 has restarted to perform the subsequent 60^o rotation from the position II' to the position III', so that the flap 11, by abutting against the front edge of the cylindrical wall 67, is overturned onto the base in a position that overlaps the flap 10. The folding element 65, by retaining the flap 10 and the wings 14-17 on the base 3, ensures perfect folding of the flap 11. During rotation from the position II' to the position III', the flap 11 is kept on the flap 10 by the wall 67 beneath which it slides, and when the drum 47 has ended its rotation through 60^o, it reaches the position III' at the welding element 68, which joins the two flaps 10 and 11.
At this point the wrapping can be considered sealed. However, in some cases it may be recommendable to perform an additional welding operation that ensures greater reliability in the closure of the wrapping. This additional sealing operation can be performed at the end of an additional 60^o rotation that moves the product at the position IV', where the additional welding element 69 is located.
By means of the subsequent 60^o rotation into the position V', the product 87 is transferred between the walls 74 and 75 which, when the clamp 48 opens, retain it elastically by virtue of the spring 77. In this retention position, the pusher 79 is already above the product, so that when the clamp 48 opens said pusher can act on the product and push it downwards beneath the lower edge of the jaws 74 and 75 which, being no longer able to retain said product, release it onto the belt 78 in front of the pusher 86 which, by accelerating due to the parallelogram 84-85, accompanies said product until it reaches the speed of the belt 78.
It should be noted that during the rotation that moves the clamp 48 into the lower position V' there is no interference between the arms 49, 50 of the clamp and the pusher 79. In fact, as more clearly shown in figure 33, the jaws 51 and 52 of the clamp 48 form, together with the respective arms 49 and 50, an L-shaped configuration allowing said jaws to pass to the side of the pusher 79, which in turn, as shown in said figure 33, protrudes laterally from the strip 80, forming a sort of inverted L-shaped configuration therewith.
The described apparatus therefore achieves the intended aim and objects. Its basic feature is that it is adaptable to the formation of various kinds of wrapping.
The apparatus in fact allows to package products with a so-called "fancy" wrapping, shown in figures 10-16 during the steps for its production. Said wrapping is normally formed by starting from a single sheet 8 which, after being centered on the product (see figure 10), is folded in a U-shaped manner, with two flaps 88 and 89 covering the longitudinal faces 6 and 7 of the chocolate (figure 11). The flaps 88 and 89 are then folded onto the base 3 (figure 12) so that the sheet 8 assumes the shape of a tube (figure 13), the ends whereof protrude from the ends 4 and 5 of the product and form two regions 90, 91, 92, and 93 for each longitudinal face.
During subsequent operating steps, first the regions 90 (figure 14) and then the regions 91 and 93 (figure 15) are folded against the ends 4 and 5. Then the wrapping is closed by folding the regions 92 onto the regions 91 and 93 (figure 16).
The apparatus for forming the wrapping of figures 10-16 is shown in figures 36-38 and differs from the apparatus of figures 32-25 essentially in the structure of some folding devices. In particular, the folding elements 36 and 43 are omitted, since it is no longer necessary to form the wings 14-17, and instead of the movable folding elements 53 and 54 there is a transverse strip 94 which, by virtue of the actuation of the parallelogram 58-60, allows to fold the flap 88 onto the base 3 of the product after said product has been gripped by the clamp 48 and released by the clamp 26 (figure 12).
The flap 89 is turned over onto the flap 88, as in the previous embodiment, by abutment against the front edge of the cylindrical wall 67.
It should be noted that if the wrapping entails two layers it is possible to activate the feeding of a second sheet by means of the device 31, which instead remains fully inactive in the single-layer case being considered. An optional second sheet can be positioned by momentarily opening the clamp 26 and momentarily retaining the chocolate by means of the roller 40, as described above.
The folding devices for closing the wrapping are located at the top of the drum 47, that is to say, in the position II'. Said devices comprise two movable folding elements 96 and 97 constituted by two levers, which are located on opposite sides with respect to the path followed by the clamps 48 and are keyed on respective shafts 98 and 99 actuated with an alternating contrarotating motion furnished by the drive unit of the apparatus. The folding elements 96 and 97 oscillate in opposition on a vertical plane passing through the axis of the drum 47 and are spaced so that in a raised position they are open so as to allow the passage of the clamps, whereas when they lower they act on the regions 90 to turn them over onto the ends 4 and 5 of the product according to the configuration shown in figure 14.
Two additional pairs of folding elements cooperate with the folding elements 96 and 97 and are rigidly coupled to two respective shafts 100 and 101 cantilevering out of the frame with axes parallel to the rotation axis of the drum 47 and actuated so as to move alternately in a contrarotating manner. The two folding elements keyed on the shaft 100 are designated by the reference numeral 102, and the two folding elements keyed on the shaft 101 are designated by the reference numeral 103; each folding element 102 is co-planar with respect to a respective folding element 103. The folding elements 102 and 103 move in opposition between a mutually spaced position, shown in figure 36, and a mutually closer position. In the spaced position, they allow the product to advance into the upper position II'; once this position has been reached, the folding elements 102 and 103 are actuated so that they move mutually closer, in order to act on the regions 91 and 93 and overturn them onto the previously folded regions 90 by virtue of the simultaneous action of the folding elements 96 and 97, so as to lead to the configuration shown in figure 15.
Then the clamp 48 performs an additional rotation through 60^o to move into the position III' at a folding device that completes the closure of the wrapping. Said folding device comprises a fork 104, the tines whereof straddle the wall 67 and end with respective folding elements 105 and 106 (figure 37) the mutual distance whereof is equal to the length of the product.
The fork 104 is actuated with a reciprocating motion that is radial with respect to the drum 47 by virtue of a parallelogram of the type already considered above for the actuation of the folding elements 53 and 54, and composed of a crank 107 (figure 36) that is driven in a reciprocating manner by the drive unit of the apparatus; the end of said crank is articulately connected to a strip 108 for the coupling of the fork 104. The end of the strip that lies opposite to the fork coupling end is articulated to a link 109 rotatably supported in the frame.
The length of the crank 107 and of the link 109 and their orientation with respect to the drum 47 are such that the folding elements 105 and 106 perform a radial back-and-forth stroke with respect to the axis of the drum 47; said stroke is such as to act on the regions 92 and fold them onto the regions 90, 91, and 93 (figure 16).
The material used for "fancy" wrapping is usually constituted by a sheet of tinfoil, and therefore the configuration of figure 15 is inherently stable, in that the folds made do not allow the wrapping to open as soon as the action of the folding elements 96, 97, 102, 203, 105, and 106 ceases. However, if a material other than tinfoil is used in which the folded flaps may have an elastic return, it is always possible to provide shoulders that extend concentrically to the sides of the drum 47 and keep the regions 92 in contact with the regions 90, 91, and 93.
After the clamp 48 has turned through a further 120^o into the position V', the product is in the region where the receiving and removal elements act.
Differently from the embodiment of figures 32-35, the receiving elements comprise an angular bracket 110 (figure 38) fixed to the footing and from the top whereof there protrudes a flat plate 111 that is coupled thereto along one edge; a cross-member 112 and a plate 113 are rigidly coupled to said flat plate and form a product receiving compartment 114 which is open on the side opposite to the flat plate 111. Four holes are formed at the corners of the cross-member 112, and respective pins 115 are driven therethrough, said pins supporting a movable plate 116 arranged opposite to the plate 113 and actuated thereagainst by springs 117 that are interposed between the cross-member 112 and the movable plate 116. The position of the movable plate 116 with respect to the fixed plate 113 is determined by abutments arranged at the ends of the pins 115 that lies outside the cross-member 112, said pins being caused to rest on the cross-member 112 by the springs 117. In this abutment position, the mutual distance of the plates 113 and 116 is slightly smaller than the width of the product, which accordingly is retained in the compartment 114 and is braked when, after being released by the clamp 48, it descends towards the removal elements. The descent of the product is positively actuated by a pusher fully similar to the one already described with reference to figures 32-35. In figures 36 and 37, the pusher and the elements actuating it are designated by the same reference numerals 79 to 82.
The pusher 79, after pushing the product downwards between the plates 113 and 116, transfers it onto the removal belt 78 in front of the spacer 86, which accelerates it in the direction E up to the speed of the belt 78, according to the technique already described above.
Another kind of wrapping widely used for the packaging of confectionery products, particularly nougats, chocolates, and candies, is shown in figures 17-25. This kind of wrapping is commonly termed "single-twist", since it has a single twisted end forming a bow and is generally constituted by two coupled sheets 8.
As shown in figures 17-25, the folding of the sheets around the product is substantially similar to the folding of the "sleeve" type and can therefore be performed with an apparatus (figures 39 and 40) modified to perform the process steps only on one side, that is to say, on one end of the product. Said process steps therefore consist in placing the inner sheet 8 over the product by means of the feeder device 22 (figure 17) and in folding the sheet 8 in a U-shaped fashion around the product, subsequently forming only the wings 14 and 15 on the side of the end 4 (figure 18). The same folding elements 36-38, but without one of the fixed folding elements 36, which is omitted to avoid forming the wings 16 and 17 on the side of the end 5, are used for this purpose. After the feeder device 31 has positioned the second sheet 9 (figure 19) and after the consequent folding by the fixed folding elements 44-45 (figure 20) and the intervention of the movable folding element 54 (figure 21), the product is transferred onto the unit 46, where the folding operations are completed, said operations consisting in folding the wing 15 onto the wing 14 by abutment against a folding element 56 (it is to be noted that the other folding element 55 is omitted) that forms the wrapping shown in figure 22, and by the intervention of the movable folding elements 65, 63, and 67a, which form the wrapping shown in figures 23 and 24. It should be noted that since the closure of the wrapping on the side of the end 5 is not required, the movable folding element 62 is also missing. In this manner, when the product moves through the 60^o angle downstream of the folding element 63 lying between the positions II' and III', the wrapping is open at the end 5, where the flaps 10 and 11 and the region 13 protrude outwardly, forming a tubular end.
After the additional 60^o rotation from the position II' to the position III' has been performed, the clamp 48 moves the product at a rotating clamp 118 that twists said tubular end. The rotating clamp 118, the structure whereof is already known and accordingly not described in detail, is composed of two jaws 119 and 120 that are articulated about a support rigidly coupled to a shaft 121 protruding from the frame of the apparatus coaxially to the product which is in each instance aligned therewith at the end of the rotation of the drum 47. The jaws 119 and 120 are oscillatably actuated in mutual opposition on a plane lying radially with respect to the shaft 121, and their actuation is synchronized with the actuation of the shaft 121, so as to grip the tubular end of the wrapping during the stops of the drum 47 and, by performing an adequate rotation, form the bow 122 (figure 25).
The subsequent steps for the advancement of the product and its transfer onto the removal belt 78 are repeated according to the technique described above with reference to the apparatus of figures 37-38.
In a manner that is similar to the one described above for forming a "single-twist" wrapping, the apparatus can be used to form a "double-twist" wrapping. In this case (see figures 41 and 42), since it is necessary to form two twists at the opposite ends of the product, it is no longer necessary to fold the regions 12-13 and the wings 14-17, and therefore the lateral fixed folding elements 36, 43 and 55, 56 and the movable folding elements 53, 54, 62, 63, 65, and 67a are omitted. The sheets 8 and 9 are simply folded in a U-shaped fashion by the fixed folding elements 37 and 38 and the flaps 10 and 11 of the U-shaped sheet are mutually superimposed, so as to form a tubular wrapping, by a movable folding element 122a and by abutment against the front edge of the wall 67. The movable folding element 122a is fixed to the arm 59 instead of the folding element 54, so as to act on the trailing flap 10 and overturn it onto the bottom of the product before the leading flap 11 is folded thereonto by the front edge of the wall 67. The tubular wrapping is then conveyed at a twisting station comprising, in addition to the rotating clamp 118, an additional rotating clamp 123 (figure 42) arranged opposite to the clamp 118 and coaxially thereto; said clamps, after gripping the opposite ends of the wrapping, twist them by means of a rotation to produce the bow 122 and the bow 124 respectively.
Finally, the apparatus is adapted for forming wrappings of the so-called "bunch" type normally used when packaging products having a substantially frustum-like or hemispherical shape.
As shown in figures 26-31, said wrapping is normally obtained with a single sheet 8 (although it is also possible to have two coupled sheets); during the rotation of the clamp 26 from the station for positioning the sheet 8 at the output of the feeder device 22, said sheet is wrapped around the product, making it pass through a stationary annular brush 125 (see figures 43, 44, and 45) that replaces the stationary folding elements 36-38. The bristles of the brush 125 have a radial arrangement allowing to fold and apply the sheet on the frustum-shaped peripheral wall of the product, so that when it exits from the brush 125 the wrapping has the shape shown in figures 27 and 28, in which the angular flaps form more or less irregular tail ends 126. The product is then rotated in the region for transfer onto the drum 47. During this path, the wrapping is preferably subjected to an additional applying operation by passing through a second brush 127 located in the place of the fixed folding elements 43 and 44.
After the product has been gripped by the clamp 48, a folding device 127a joins the tines of the fork 59 in a bridge-like fashion and folding devices, fully identical to those previously designated by the reference numerals 62 and 63, turn over the tail ends 126 onto the base of the product (figures 29 and 30), while the wrapping is closed by the abutment of the last flap against the edge of the wall 67 (figure 31). Two pads 128 and 129 are provided along the path from the top of the drum 47 (position II') to the point for transfer onto the removal belt 78 (position V'), said pads being fixed to the ends of levers 130 and 131 that are oscillatably actuated so as to compress the tail ends 126 onto the base 3, preventing them from lifting.
It is possible to apply a second sheet 9, to be coupled over the sheet 8, in "bunch"-type wrapping as well. The sheet 9 is fed by the device 31 while the jaws 29 and 30 are open and the product is retained by the roller 40.
As clearly shown by the above description, the described apparatus perfectly achieves the intended aim and objects. In particular, the apparatus provides wrappings having highly different shapes after undergoing simple modifications according to the product to be packaged.
For example, the apparatus can be easily adapted to the forming of products commonly termed "Boero", having a substantially hemispherical shape.
As shown in figures 46 and 47, the wrapping for such a product is similar to the one previously referenced as "single-twist", the difference being that the twist is arranged opposite to the base 3.
For this purpose, at the exit of the feeder conveyor 18 there is provided a stop element 132 fixed to the end of a lever 133 and located above the plane of the conveyor, so as to stop the incoming products.
The lever 133 is keyed on a shaft 134 rotatably supported in a box 135 that is provided with means for fixing it to the frame of the apparatus.
An arm 136 is furthermore rigidly coupled to the shaft 134 and has a fork 137, the tines whereof form a radial slot in which a pin 138 is engaged.
The pin 138 is fixed to an arm of an L-shaped lever 139 pivoted in the box 135.
A clamp 139 is formed in the arm 137 and fixes a roller 140 that follows a cam 141 adapted to impart a small oscillating movement to the lever 133, said movement, by means of the fork 137, actuating the lever 139 so that it oscillates in the opposite direction and performs longer strokes in view of the ratio between the lengths of the arms involved.
The lever 139 supports, at its end, a wing 142 protruding transversely above the conveyance plane of the conveyor 18 and assumes two positions under the control of the cam 141. In one position, shown in figure 49, the wing 142 and the stop element 132 are arranged so as to form a seat in which the incoming products 1 are retained at the top and at the front to prevent the accumulation thrust from causing an incorrect arrangement of said products and specifically of the product that rests on the abutment 132 and must be transferred into the apparatus.
In the other position, the wing 142 is raised from the conveyor 18, so as to release the product to allow to pick it up in an upward direction.
In order to pick up the product, there is a clamp 143 oscillating on a plane that lies at right angles to the rotation plane of the drum 25 and replacing the clamp 19 of the apparatuses shown in the previous figures.
As shown in figure 48, the clamp 143 comprises a jaw 144 rigidly coupled to an arm 145 that is radially rigidly coupled to a sleeve 146 slidingly supported in the box 135 at right angles to the rotation axis of the drum 25.
A shaft 147 is guided inside the sleeve and radially supports an arm 148 parallel to the arm 145. The jaw 149 is mounted at the end of the arm 148 and is guided parallel to the shaft 147 by means of a stem 150. A spring 151 is arranged between the arm 148 and the jaw 149 and pushes said jaw 149 against the jaw 144.
The shaft 147 and the sleeve 146 are mutually rotationally coupled but can slide axially with respect to each other and are actuated in opposition by virtue of conventional actuation means, accommodated in the box 135 and controlled by the drive unit of the apparatus.
In order to form the "Boero", the incoming products are initially positioned by the abutment 132 and by the wing 142. The clamp 143 is in the position in which its jaws 144 and 149 are at the sides of the product, which is in direct contact with the stop element 132 (position shown in dashed lines in figure 49).
At this point the sleeve 146 and the shaft 147 are actuated in opposition, so as to grip the product at two diametrically opposite points. By virtue of the spring 151, the product remains secured elastically between the jaws 144 and 149.
As soon as the cam 141 has actuated the spacing of the stop element 132 and the lifting of the wing 142, the rotation of the clamp 143 is actuated; after a 90^o angle, said clamp transfers the product between the jaws 29 and 30 of a respective clamp 26 of the drum 25.
The coupling of the sheet 8 fed by the unit 22 and of an optional additional sheet 9 with the product, the folding of the wrapping, and the forming of the twist are all performed with the techniques described above in relation to the apparatus of figures 39 and 40.
A package as shown in figure 47, in which the twist lies opposite to the base of the product, is obtained at the output of the apparatus.
A fundamentally important feature of the invention is that the arrangement of the two clamp supporting drums 24 and 46 allows to place folding devices that meet several folding requirements. The folding devices required for some kinds of wrapping can in fact be simply disengaged or deactivated when the apparatus must operate on wrappings of a different kind. In any case, the operations for adapting the apparatus are easy to perform and do not require the intervention of highly specialized personnel. It is to be noted, in this regard, that if one wishes for example to convert the apparatus of figures 32-35 into the apparatus of figures 43-45 it is sufficient to replace the folding elements 36-38 and 43-45 with the brushes 125 and 127 and to replace the welding elements 68 and 69 with the pads 128 and 129. Likewise, when one wishes to convert the apparatus to produce a "fancy" wrapping, it is possible to replace the entire head supporting the movable folding elements 62, 63, and 65 with another head supporting the folding elements 96, 97, 102, 103, 105, 106. In any case, no operations for adjusting the operating steps are required; all of said steps continue to be drawn from a single central actuation shaft.
Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

Apparatus for packaging various products, particularly confectionery products having various shapes, in a wrapping that comprises at least one sheet (8), said apparatus being characterized in that it comprises a conveyor (18) for the products (1), which feeds individual products to be packaged; a feeder (21) for said sheet (8), which has means (20) for positioning said sheet on a product; a first unit (24) and a second unit (46) rotating about parallel and horizontal axes, each unit supporting a plurality of clamps (26, 48) angularly equidistant and provided with jaws (29, 30; 51, 52) having a tangential grip line; said units (24; 46) being actuated with an intermittent motion and with angular strokes that are equal to the angular distance between said clamps; said units being mutually synchronized so that when they are in the stop position a first clamp (26) of a first unit (24) is in the position for gripping said sheet (8) and said product (1) and a second clamp (26) of the same unit (24) is in an angular position in which its grip line is at right angles to the grip line of a clamp (48) of the other unit (46); said clamps (26; 48) being actuated, during the stops in the rotation of the units, so that while said first clamp (26) grips the product (1) and the sheet (8), said second clamp (26) opens to release the product (1) and the sheet (8) to a clamp (48) of the second unit the grip line whereof lies at right angles to the grip line of said second clamp (26) of the first unit (24); said apparatus being furthermore characterized in that it comprises stationary folding devices (36-38, 55, 56; 67; 125) that act on the sheet (8) during the rotation of the units and cooperate with movable folding devices (53, 54; 62, 63; 127a) that act on the sheet during the stops in the rotation of the units; said folding devices being arranged along the path followed by said clamps (48) and being adapted to complete the folding of the sheet around the product; means being furthermore provided for receiving (74, 75; 112-117) and transferring (79, 80) the packaged product onto a removal element (78).
Apparatus according to claim 1, characterized in that said means for positioning the sheet on the product comprise a surface (20) arranged radially with respect to said first unit (24) at the output of said product conveyor (18) and provided with an opening (23) on which a sheet (8), fed by said device (22), is placed; said opening (23) being located along the path followed by the jaws (29, 30) of the clamps (26) of said first unit (24); said product (1) being fed at said opening (23) between said sheet (8) and the underlying jaw (29) of the clamp (26) so that the closure of the clamp (26) produces the engagement of said sheet (8) and of said product (1).
Apparatus according to one of claims 1 and 2 for forming a wrapping of the "sleeve" type (figures 1-9 and 32-35), characterized in that it comprises, along the path of the clamps of said first rotating unit (24), two first fixed folding elements (37, 38) that are adapted to fold the sheet (8) in a U-shaped fashion around the product and to form an outer flap (11) and an inner flap (10) with respect to the rotation axis of the first unit (24) and at right angles to the rotation plane of the clamps (26), said flaps (10, 11) extending from the grip plane of the respective clamp in a tangential direction opposite to the direction of rotation of the first unit; two additional fixed folding elements (36) that are adapted to fold the regions (12, 13) of the sheet (8) that lie between said flaps (10, 11) and to form two wings (14,17) at the opposite sides of each flap; a folding device (53, 54) movable in a direction that is parallel to the direction of the grip plane and adapted to fold the wings (14, 16) of the inner flap (10) onto said regions (12, 13) after the product has been transferred from a clamp (26) of the first unit (24) to a corresponding clamp (48) of the second unit (46); two shoulders (55, 56) provided along the path of the clamps (48) of said second unit (46) and at the sides thereof, which form a channel for the passage of the clamps (48), and are provided with front edges acting on the wings (15, 17) of the outer flap (11) to fold them onto the already-folded wings (14, 16) of the inner flap (10), so as to produce an open wrapping wherein the two outer and inner flaps (11, 10) respectively arrange themselves downstream and upstream with respect to the rotation of the second unit (46); two folding elements (62, 63, 62a, 63a) that can move in mutual opposition and oscillate on a plane that is radial with respect to the second unit (46) to fold said wings (14,17) onto the face of the product that is comprised between said flaps (10, 11); a movable folding element (65) that is tangent to said clamps (48) and overturns said trailing flap (10) onto said folded wings (14-17), said movable folding elements (62, 63, 62a, 63a; 65) being activated during the stops in the rotation of said rotating units (24; 46); a stationary cylindrical wall (67) that is concentric to said second unit (46) and has a front edge for folding the leading flap (11) over said already-folded trailing flap (10), thus closing the wrapping, said wall (67) being adapted to retain said wrapping in a closed condition until it reaches said receiving means (74, 75) and said transfer means (79, 80).
Apparatus according to one of claims 1 and 2 for providing a wrapping of the "fancy" type (figures 10-16 and 36-38), characterized in that it comprises, along the path of the clamps (26) of said first rotating unit (24), two first fixed folding elements (37, 38) for folding the sheet in a U-shaped fashion around the product and forming an outer flap (11) and an inner flap (10) with respect to the rotation axis of the first unit (24) and at right angles to the rotation plane of the clamps (26), said flaps (10, 11) protruding from the grip plane of the respective clamp (26) in a tangential direction that is opposite to the direction of rotation of the first unit (24); a folding device (94) that can move in a direction parallel to the direction of the grip plane and is adapted to fold the inner flap (10) onto the face of the product that lies opposite to the grip face after the product has been transferred from the clamp (26) of the first unit (24) to a corresponding clamp (48) of the second unit (46); a cylindrical wall (67) that is concentric to said second unit (46) and has a front edge adapted to fold the leading flap (11) over said already-folded trailing flap (10), thus forming a tubular wrapping (figure 13); characterized in that along the path of the clamps (48) of said second unit (46) and at the sides thereof there are a first pair of folding elements (96, 97) oscillating in mutual opposition on a plane that lies radially with respect to the axis of said second unit (46) and two additional pairs of folding elements (102, 103) oscillating in mutual opposition on planes that lie laterally to the clamps and at right angles to the axis of said second unit (46) and cooperate with said first pair of folding elements (96, 97) so as to partially fold the opposite ends (90-93) of the tubular wrapping; and in that there is also provided a third folding element (104) that can move radially, is located downstream of said two pairs of folding elements (96, 97; 102, 103), and is adapted to complete the folding of the opposite ends (92) of the wrapping; said wall (67) being adapted to retain said wrapping in a closed condition until it reaches said receiving means (112-117) and said transfer means (79).
Apparatus according to one of claims 1 and 2 for forming a wrapping of the "single twist" type (figures 17-25, 39-40), characterized in that it comprises, along the path of the clamps (26) of said first rotating unit (24), two first fixed folding elements (37, 38) for folding the sheet (8) in a U-shaped fashion around the product (1) and forming an outer flap (11) and an inner flap (10) with respect to the rotation axis of the first unit (24) and at right angles to the rotation axis of the clamps (26), said flaps (10, 11) extending from the grip plane of the respective clam (26) in a tangent direction that is opposite to the direction of rotation of the first unit (24); an additional fixed folding element (36) for folding a lateral region of the sheet (8) that lies between said flaps (10, 11) and forming two wings (14, 15) on the same side of each flap; a folding device (54) that can move parallel to the grip plane and is adapted to fold the wing of the inner flap (10) onto said region (12) after the product (1) has been transferred from the clamp (26) of the first unit (24) to a corresponding clamp (48) of the second unit (46), a shoulder (56) being provided along the path of the clamps (48) of said second unit (46) and on the side wherefrom said wings (14, 15) protrude, said shoulder having a front edge acting on the wing (15) of the outer flap (11) to fold it onto the already-folded wing (14) of the inner flap (10), so as to produce an open wrapping wherein the outer and inner flaps (11, 10) are respectively arranged downstream and upstream with respect to the direction of rotation of the second unit (46); a movable folding element (63) oscillating in a plane that lies radially with respect to the second unit (46) so as to fold said wings onto the face of the product that is comprised between said flaps (10, 11); a folding element (65) that is tangent to said clamps (46) and is adapted to overturn said trailing flap (10) onto said folded wings (14, 15); said folding elements (54, 63, 65) being activated during the stops in the rotation of said rotating units (24, 46); a stationary cylindrical wall (67) that is concentric to said second unit (46) and has a front edge for folding the leading flap (11) over said already-folded trailing flap (10), thus closing the wrapping so as to form a tube having an open end that protrudes on the side opposite to the one that is closed by said folded wings (14, 15), said wall (67) being provided to retain said wrapping in the tubular condition up to an angular position at which there is a rotating clamp (118) for gripping, during the stops in the rotation of the second unit (46), said open end of the tubular wrapping and twisting it so as to form a bow (122) and then releasing it so as to allow the transfer of the product towards said receiving means (112-117) and said transfer means (79).
Apparatus according to one of claims 1 and 2 for forming a wrapping of the "double-twist" type (figures 41, 42), characterized in that it comprises, along the path of the clamps (26) of said first unit (24), two fixed folding elements (37, 38) for folding the sheet in a U-shaped fashion around the product and forming an outer flap (11) and an inner flap (10) with respect to the rotation axis of the first unit (24) and at right angles to the rotation plane of the clamps (26), said flaps (10, 11) protruding from the grip plane of the respective clamp (26) in a tangent direction that is opposite to the direction of rotation of the first unit (24), so as to form a wrapping wherein, when the product is transferred from a clamp (26) of the first unit (24) to a corresponding clamp (48) of the second unit (46), said outer flap (11) and said inner flap (10) are respectively arranged downstream and upstream with respect to the rotation of the second unit (46); a folding device (122a) that is tangent to said clamps (46) of the second unit (44) and operates during the stops in the rotation of said unit so as to fold said trailing flap (10) onto the product (1); a stationary cylindrical wall (67) that is concentric to said second unit (44) and has a front edge that is adapted to fold the leading flap (11) over said already-folded trailing flap (10), thus forming a tubular wrapping wherein the opposite ends are open and protrude on opposite sides with respect to the clamp (46) retaining the product; said wall (67) being provided to retain said wrapping in the tubular condition up to an angular position at which there are two coaxial and oppositely arranged rotating clamps (118, 123) that are adapted to grip, during the stops in the rotation of the second unit (44), said open ends of the tubular wrapping and twist them so as to form a double bow (122, 123) and then release them so as to allow the transfer of the product towards said receiving means (112-117) and said transfer means (79).
Apparatus according to one of claims 1 and 2 for forming a wrapping of the "bunch" type (figures 26-31, 43-45), characterized in that it comprises, along the path of the clamps (26) of said first unit (24), a fixed folding element constituted by an annular brush (125) provided with radial bristles protruding inwardly and adapted to apply a sheet (8) onto the product (1) that passes through said brush (125) and to form a wrapping with tail ends (126) extending from the clamp grip plane in a tangent direction that is opposite to the direction of the rotation of the first unit (24); a folding device (127a) that can move parallel to the grip plane and is adapted to fold the tail ends (126) of the wrapping upstream onto the face of said product that is opposite to the grip face after the product has been transferred from a clamp (26) of the first unit (24) to a corresponding clamp (48) of the second unit (46), two folding elements (62, 63) being furthermore provided along the path of the clamps (48) of said second unit (46), said folding elements being movable in opposition and oscillating on a radial plane so as to fold the lateral tail ends of the wrapping onto the previously folded tail ends; a stationary cylindrical wall (67) that is concentric to said second unit (46) and has a front edge that is adapted to fold the leading tail ends onto the already-folded lateral tail ends, thus closing the wrapping; said wall (67) being provided to retain said wrapping in the closed condition until it reaches said receiving means (74) and said transfer means (78).
Apparatus according to one of claims 3 to 7, characterized in that it comprises an additional device (31) for feeding a second sheet (9) arranged downstream of said device (22) for feeding the first sheet (8), means for positioning the second sheet (9) on the first sheet (8) being arranged at the output of said device, said means comprising a surface (34) arranged radially with respect to said first unit (24) and provided with an opening (35) whereon said second sheet (9), fed by said additional device (31), is placed; said opening (35) being arranged along the path followed by the jaws (29, 30) of the clamps (26) of said first unit (24), said fixed folding means (36-38; 125) being arranged between said feeding devices (22, 31), additional fixed folding means (43-45, 127) being provided downstream of said additional device (31); said apparatus being furthermore characterized in that a roller (40) is arranged between said radial surface (34) and the first folding means (36-38, 125) and is mounted at the end of a lever (41) that is articulated and actuated by a spring (42) so as to secure the product against an abutment (37) to allow to momentarily open the clamp (26) retaining said product (1) and to insert the second sheet (9) between the product (1) and the jaw (30) of the clamp (26), downstream of said product, so that said additional fixed folding devices (43-45, 127), downstream of said additional device (31), fold the second sheet (9) onto the first sheet (8).
Apparatus according to one of claims 3, 5, and 8, characterized in that it comprises a movable shoulder (67a) that can oscillate in a position that is radial with respect to said second unit (44) so as to support said trailing flap (10) before the tangent folding element (65) intervenes.
Apparatus according to one of claims 3, 5, and 8, characterized in that it comprises welding elements (130, 131) arranged downstream of said folding devices and provided to mutually weld said flaps (10, 11) to seal the closure of the wrapping.
Apparatus according to one of claims 7 and 8, characterized in that it comprises presser elements (130, 131) arranged downstream of said folding devices and provided to compress the folded tail ends (126) of said wrapping onto the product.
Apparatus according to one of the preceding claims, characterized in that said product receiving and transfer means comprise two walls (74, 75) that are superimposed on a removal belt (78) lying below said second rotating unit (46) and are actuated in opposition by elastic means (77); said walls (74, 75) being adapted to elastically retain a product (1) that has been transferred therebetween; a pusher element (79) being provided which is actuated with a reciprocating motion, acts on the product (1) retained between said walls (74, 75) and pushes it onto said removal belt (78).
Apparatus according to claim 12, characterized in that said walls (74, 75) are articulated along one edge and are supported so as to allow the clamps (48) of said second rotating unit (46) to insert the products between said walls.
Apparatus according to claim 12, characterized in that said walls are constituted by a fixed wall (113) and by a movable wall (116) that is pressed against said fixed wall by elastic means (117), a pusher element (79) being provided, said pusher element being actuated with a reciprocating motion and being adapted to transfer said products from said clamps (48) of said second rotating unit (46) between said walls (113, 116) and then onto said belt (78).
Apparatus according to one of the preceding claims, characterized in that it comprises a pusher (86) actuated with a back-and-forth motion on said removal belt (78) and adapted to space the products (1) transferred onto the belt (78) along the advancement direction thereof.
Apparatus according to one of the preceding claims, characterized in that the elements (53, 54; 86) that move reciprocatingly are actuated by an articulated parallelogram comprising a crank (58; 81) that is oscillatably actuated and a link (60; 82) one end whereof is articulated to a fixed point and the opposite end whereof is articulately connected to a strip (59; 80) for the coupling of said element.
Apparatus according to one of the preceding claims, characterized in that said product conveyor comprises a belt (18) for conveying the products and a clamp (19) arranged at the output of said belt (18) and provided with a reciprocating motion in a direction at right angles to the rotation plane of said first unit (24); said clamp (19) being actuated between a position for gripping a product on the belt (18) and a position for placing said product in front of said opening (23), at which said clamp (19) is actuated so that it opens in order to transfer said product to a clamp (26) of said first rotating unit (24).
Apparatus according to one of the preceding claims 5, 8, 9-16, particularly for forming a so-called "single twist" wrapping for products known as "Boero", characterized in that it comprises a product conveyor composed of a product conveyor belt (18), a stop element (132) arranged at the output of said belt (18) to stop the incoming products, and a clamp (143) arranged at the output of said belt (18) and adapted to grip the product in abutment against said stop element (132) at two points that are arranged oppositely with respect to the product advancement line, said clamp (143) oscillating between a product grip position and a position for releasing the products to the clamps (26) of said first unit (24) along an orientation rotated through 90^o with respect to the grip plane.
Apparatus according to claim 18, characterized in that said oscillating clamp (143) comprises two jaws (144, 149) that are respectively rigidly coupled to a sleeve (146) guided in a box-like body (135) at right angles to the rotation axis of said first unit (24) and to a shaft (147) that is guided in said sleeve (146), said shaft (147) and said sleeve (146) being controlled by actuation means in order to actuate them in mutual opposition.
Apparatus according to claims 18 or 19, characterized in that said stop element (132) is rigidly coupled to a lever (133) that oscillates on a plane parallel to said conveyor (18) and is actuated by a cam (141) so as to move away from the product (1) that is in abutment against said stop element (132) when said product has been gripped by said oscillating clamp (143).
Apparatus according to claim 20, characterized in that it comprises an additional lever (136) that oscillates on a plane parallel to said conveyor (18) and is provided with a wing (142) lying above said products, said lever (133) being operatively associated with said cam (141) so as to oscillate between a lowered position, which forms a seat for retaining the product in abutment against said stop element (132), and a raised position, which allows to transfer the product in abutment by means of said oscillating clamp.