WO2003091104A2

WO2003091104A2 - Machine for wrapping a pasty, liquid or semi-liquid product

Info

Publication number: WO2003091104A2
Application number: PCT/IB2003/001625
Authority: WO
Inventors: Mauro Bianchi
Original assignee: Corazza S.P.A.
Priority date: 2002-04-24
Filing date: 2003-04-22
Publication date: 2003-11-06
Also published as: ITBO20020237A1; EP1506118A2; WO2003091104A3; AU2003216695A8; AU2003216695A1; ITBO20020237A0

Abstract

In a machine for wrapping a pasty, liquid or semi-liquid product, and in particular, a processed cheese or similar product, the wrapper is made from a flat sheet that is folded to form a shell-like body or container, and another flat sheet placed over the shell to form the wrapper cover. The machine comprises a supporting frame (12), means for preparing the wrapper sheets including means (14, 16) for cutting the sheets from a respective web of material unwound from a roll, means for preparing the cover sheets (C) including means (70) for cutting the sheets (C) from a respective web (74) of material (72) unwound from a roll (74), means (38) for folding each wrapper sheet to form a shell; means (39) for filling the product into the shell, and means for closing the shell including means (48) for placing over the shell a corresponding cover sheet cut by the cutting means (70). In the machine according to the invention, the means (70) for cutting the cover sheets (C) are located well away from the means (39) for filling the product into the wrapper shell.

Description

An improved machine for wrapping a pasty, liquid or semi-liquid product

Technical field

The present invention relates to a machine for wrapping a pasty, liquid or semi-liquid product, and in particular, a processed cheese or similar product. The wrapper for the product is made from a flat sheet of material, normally aluminium foil, having an appropriate shape, for example triangular, which is folded to form a shell-like body or container having a required shape, for example the shape of a solid with a triangular base, and a cover wrap consisting of another flat sheet of material having an appropriate shape, for example triangular, smaller in size than the sheet used to make the wrapper shell.

Background art In the field of machines for wrapping pasty, liquid or semi- liquid products, in particular, processed cheese, the need is felt for machines that do not contaminate the processed product or that reduce contamination to a minimum.

More specifically, the need is felt for machines that are easy to clean and where the risk of contamination is minimised.

It would therefore be especially desirable to have a machine without inaccessible parts, that is to say, a machine without sites where dirt, wrapper waste material or residue of the product being wrapped can accumulate and give rise to contamination. According to another aspect, it would also be especially desirable to minimise contamination by process waste.

Indeed, the operations required to prepare the different parts of the wrapper normally produce waste particles that easily find their way inside the wrapper together with the food product, thus contaminating it and making it unsuitable for use as a food. Processed cheese wrapping machines known to prior art essentially comprise a supporting frame, means for preparing the wrapper sheets including means for cutting the sheets from a respective web of material unwound from a roll, means for preparing the cover sheets including means for cutting the sheets from a respective web of material, means for folding the wrapper sheet to form a shell, means for filling the product into the shell, and means for closing the shell including means for placing over the shell a corresponding cover sheet cut by the cutting means.

In prior art machines of this kind, the wrapper cover is cut from a web of material in an area above and adjacent to the filling area and is transferred by the cutting means directly to the means that apply it to the shell that has been filled with product.

Thus, in the filling area, the food product is exposed to a serious risk of contamination by waste aluminium particles resulting from the cutting operations.

Summary of the invention

To overcome this problem, the invention contemplates the provision of means for separating the drive area from the wrapper forming area.

More specifically, the separating means comprise a wall which extends in the lengthways direction of the machine.

In particular, the separating means comprise at least one mobile surface from which the shafts used to drive the wrapping parts of the machine extend.

Thus, dirt, and in particular the lubricants used in the drives (motors, and transmission and drive mechanisms) do not contaminate the food product being wrapped.

According to another advantageous aspect of the present invention, the means for cutting the cover sheets are located well away from the means for filling the product into the wrapper shell.

Thus, the quantity of cutting waste that reaches the food product is minimal and does not contaminate it. According to another aspect, the cover sheet cutting means are positioned below the level at which the cover sheets are placed over the food product, so that cutting waste particles, which fall under the effect of gravity, do not contaminate the food product .

According to another aspect, the invention contemplates the provision of at least one partition separating the product dispensing means from the means for cutting the wrapping materials . Means are also advantageously provided for feeding and conveying the cover sheets to the area where they are applied.

According to yet another advantageous aspect, the means for feeding the wrapper being formed comprise a flat flexible lamina that supports a plurality of longitudinally spaced supporting elements. A conveyor made in this way is quick and easy to sanitise .

According to yet another advantageous aspect, there are blocks for supporting the wrapper cover sheets and/or blocks for supporting the wrapper shells, these blocks being separably connected to the conveyor, in particular to the continuous longitudinal drive means of the conveyor. This greatly facilitates sanitising operations and appreciably reduces machine down time for cleaning the supporting elements.

The invention also advantageously contemplates the provision of means for driving the parts that operate on the wrappers, said means comprising a longitudinal base plate and means for driving the base plate; the means for driving the base plate L comprise means for driving or oscillating through an angular interval, and means for compensating the movement imparted by the first drive means, in such manner that the working parts mounted on the longitudinal base plate L are made to follow a substantially horizontal path parallel to the path followed by the wrappers.

Other advantageous aspects of the machine according to the present invention are set out in the claims. Brief description of the drawings

The technical characteristics and advantageous aspects of the invention are apparent from the detailed description which follows, with reference to the accompanying drawings, which illustrate a preferred embodiment of the invention provided merely by way of example without restricting the scope of the inventive concept, and in which:

Figure 1 is a schematic side view of a wrapping machine according to the present invention; - Figures 2 and 3 show two different working positions of the cover sheet cutting means in the machine according to the present invention;

Figure 4 is a cross section of the part of the machine according to the invention where the wrapper cover sheets are picked up and transferred;

Figure 5 is a top view of the block for supporting and transferring the wrapper cover sheets according to the invention;

Figures 6 and 7 are longitudinal sections of the means for picking up and positioning the wrapper cover sheets in two different working positions;

Figure 8 schematically illustrates the means for driving the working parts of the machine according to the invention.

Description of the preferred embodiments of the invention Figure 1 illustrates a longitudinal side view of the working part of the machine for wrapping a pasty product, in particular processed cheese, in suitable wrappers, preferably in the shape of a triangle or circular sector, essentially comprising a shell-like body made by folding a flat sheet of substantially triangular shape cut from a web of aluminium foil that is sealable on one side and closed by a cover, also made from a flat sheet with a substantially triangular shape but smaller in size than the sheet used to make the shell, and cut from a web of aluminium foil that is sealable on one side. As illustrated, the machine 10 extends principally lengthways and comprises a mounting frame 12 and a plurality of devices used to make the wrappers. More specifically, the invention contemplates the provision of means for preparing the wrapper sheets including means (not illustrated in Figure 1) for unwinding a web of aluminium from a roll, cutting means, consisting of a rotary knife, labelled 14 in Figure 1, located at a transversal end of the machine, labelled Tl in Figure 1.

The cutting means 14 for making the wrapper sheets cut a web of aluminium foil into suitably shaped longitudinal strips, the web being fed in a direction transversal to the longitudinal direction in which the machine extends being the principal direction in which the wrappers or wrapper elements are fed. Advantageously, the cutting operations are performed as the web moves forward with continuous feed motion.

The cutting means 14, the web roll, the means for feeding the web, and the other working devices, are mounted on a transversal wall 12' of the frame.

The suitably shaped longitudinal strips, are then cut transversely at 16 using a similar rotary knife but with a transversal cutting blade, which enables the strips to be cut into separate sheets with a generally triangular shape.

To reach this unit, the web cut into strips must be turned through 90° in such manner that the strips are moved apart and their direction of feed changes from transversal to longitudinal.

Each wrapper sheet cut in this way is delivered by the unit 18 to the revolving assembly unit 20 which has already received from the unit 22 the tear strip for opening the wrapper of the processed cheese portion.

The machine also comprises means, labelled 24 in Figure 1, for cutting tear strips from a tape 26 of plastic film unwound from a corresponding roll 28.

The cutting of the tear strips occurs with stop/start motion, the tear strips being cut and delivered to the tear strip conveyor means 22 while the latter are stopped, and then transferred to the assembling means 20 while the latter are in motion.

The numeral 19 in Figure 1 denotes the means or roller for heating and sealing the tear strips to the wrapper sheets. Downstream of the area where the tear strips and wrapper sheets are delivered, there are means for dispensing a label to each sheet on the side opposite that where the tear strip is applied, said means being denoted in their entirety by the numeral 30 in Figure 1. These means comprise a transfer belt 31 that delivers a label to each sheet while the assembling means 20 rotate .

The means for transferring the wrapper sheets are denoted in their entirety by the numeral 32. These transfer means consist of a conveyor belt and carry the wrapper sheets towards the means that feed them while the wrapper is being formed, the latter means consisting of an endless conveyor, labelled 34, which is trained around end wheels 36, 38.

The conveyor 34, which has an active upper section and a lower return section, comprises a flexible lamina of stainless steel and presents a plurality of elements for supporting the wrappers being formed and the covers to be placed over them, as described in more detail below.

The area where the wrappers are formed includes means for folding each wrapper sheet to form a shell, the folding means being labelled 38 in their entirety and being preferably of the type described in more detail in European patent application EP 1094005, in the name of the same Applicant as the present, the disclosure of which is incorporated herein by reference. The sheets pass from the transfer means 32 to the conveyor means 34 that feed them to the upper surface of the hopper, push them through the hopper and feed them out in the folded shell shape onto the supporting elements 35.

The machine according to the invention extends lengthways and, downstream of the forming area, includes means for filling the pasty product into the wrapper shells, said filling means comprising dispensing nozzles 40 mounted on a mobile unit 42 enabling a charge of pasty product to be dispensed into each wrapper shell while the wrapper shells continue moving continuously.

In Figure 1, the unit for dispensing the food product is denoted in its entirety by the numeral 39. For applying the covers to the wrapper shells filled with pasty product, there is a unit downstream of the unit 39.

This unit is labelled 44 and comprises means 46 for gripping and releasing the covers, which are carried by supporting and drive means 48 to perform a reverse movement such that they can be placed on the shells travelling on the conveyor 34. The covers are applied while the conveyor 34 moves and the means 46 carrying the covers move lengthways at the same speed as the conveyor, and in the same way as the dispensing nozzles and the other wrapping parts downstream.

The unit 44 for applying the covers is described in more detail below.

The numeral 50 denotes means for folding the upper flaps of the shell over the cover so as to retain the latter. These folding means comprise folding elements, labelled 52, which fold the upper portions of the side walls of each wrapper shell, constituting flaps for closing the top of the wrapper, in such a way as to position the flaps horizontally over the cover while the wrapper shells continue moving. The numeral 54 denotes means for supporting and driving the folding elements 52, said means being similar to the ones for the product dispensing nozzles and for applying the covers.

Similarly, the numeral 56 denotes means for sealing the covers to the shells and comprising sealing elements 58 and means, labelled 60 in their entirety, for supporting and driving the sealing elements 58 in such a way that the sealing elements follow the continuous motion of the wrapper shells.

The numeral 62 denotes means, not illustrated in the accompanying drawings, for transferring the wrappers to the conveyors that feed them to the collating device 68. The device 68 is located at the end T2 of the machine.

As illustrated, the transfer means are driven by means, labelled 64, similar to the drive means of the other working parts of the machine and comprising means, labelled 66, for engaging and transferring the fully wrapped processed cheese portions.

In the upstream area of it, the machine also includes means for preparing the cover sheets, said means comprising elements, labelled 70, for cutting and delivering the cover sheets from a web of aluminium foil 72 unwound from a roll 74.

More specifically, using the available to best advantage, the cutting elements are located under the means 32 that transfer the wrapper sheets from the area where the wrapper sheets are prepared to the area where the wrapper shells are formed.

As can be seen in Figure 1, these cutting means are located at a level below the height at which the product dispensing nozzles work and also below the level of the wrapper feed belt. Means are provided for gripping, transferring and delivering the cover sheets to the means that convey the cover sheets to the area where they are applied to the filled wrapper shells.

The means for delivering the cover sheets take the form of a revolving element, schematically illustrated in Figure 1, denoted by the numeral 76. The means for picking up, transferring and delivering the cover sheets comprise pickup elements 78, which, as the element 76 revolves, impinge, at an angular position downstream of the pickup position, on elements for conveying the cover sheets located on the conveyor belt 34 at alternate positions relative to the recessed supporting elements 35 carrying the wrapper shells.

The elements 80 for picking up and conveying the cover sheets are aligned with the recessed elements 35 for supporting the wrapper shells, as described in more detail below. The cover sheet carried by one of the supporting elements 80 is associated by the aforementioned cover sheet transfer drive elements 48, with a wrapper shell located in the supporting element 35 immediately following the supporting element 80.

A partition wall, schematically illustrated and denoted by the numeral 84, is provided between the area where the wrapper materials are cut and formed and the area where the pasty product is dispensed by the nozzles 40 into the wrapper shells. The partition wall has an opening 83 at the top of it to allow the passage of the active section 34' of the conveyor 34 and an opening 35' at the bottom of it to allow the passage of the return section 34" of the conveyor 34. The partition 84 thus keeps the dust resulting from cutting operations on the wrapper materials in a well-defined upstream area of the machine, preventing it from reaching the product dispensing area where the product is exposed. The partition - which may isolate the different parts of the machine almost completely from each other, as in this case - might only partly isolate the parts of the machine it divides, leaving spaces open where the infiltration of cutting waste and dirt is unlikely. For example, the partition wall 84 might be limited to the upper area of the machine, just above and just below the active section of the conveyor 34. Whatever the case, the special design of the conveyor 34 itself constitutes a barrier against the infiltration of waste to a certain extent.

The machine also features a longitudinal cover CT that isolates the working area and has a plurality of doors SP for accessing the different components of the machine. Figure 2 illustrates the area where cutting of the wrapper cover sheet is performed.

The web 72 of aluminium foil of suitable thickness is trained around a series of feed rollers 102, 104 and drive rollers 106 located upstream of the cutting means 70. The cutting means 70 comprise a head 108 mounted on a stem

110 which moves the head in a straight line, indicated by the arrow F in Figure 2, from a forward cutting position to a retracted position of passage between the head 108 and the corresponding cover sheet contact means consisting of a respective head 112 mounted on the transfer and delivery means 76.

The transfer and delivery means 76 have on them a plurality of these contact cover sheet contact and retaining heads 112 mounted on a revolving body 114. In the embodiment illustrated, there are four heads 112 positioned at angular intervals of 90° from each other.

Below is a brief description of the way the cover sheets are cut. When the web 72 is positioned between the cutting head 106 and the contact and retaining head 112, web 72 feed is stopped and the head 106 is moved forward, relative to the frame portion 107 that supports in axially mobile fashion the stem 108 which mounts the head 106, in such a way that the front plate 116 of the head 106 carries the cutter blade against the opposing surface 118 of the contact and retaining head 112 having air suction holes in it for retaining the cover sheet C on it after it has been cut on the surface 118. During this stage, the wheel 114 that mounts the contact and retaining heads 112 is kept stationary. The front plate 116 of the cutting means 70 also features a lock pin 120 that fits into a matching hole in the front portion 117 of the head 112 so as to securely hold the cutting head relative to the cover sheet contact and retaining head 112.

Once the cut has been performed, the cutting head is retracted to enable the wheel 114 to turn, carrying the cover sheet C supporting and conveying units towards the means for gripping and conveying the cover sheet towards the application area.

Figure 3 illustrates the transfer of the cover sheet, with the assembly 112, 114 kept in a condition of angular motion, without stopping the feed motion, so as to enable the cover sheet to be transferred. Thus, the conveyor belt 34 continues moving. In practice, each cover sheet is delivered to the respective support 80 at a point in time between the moment one pickup element 112 reaches the cover sheet cutting means and the moment the next pickup element reaches the same cutting means.

For this purpose, the cover sheet on the supporting unit 112 is transferred by interference with a suitable surface 140 of it that engages and retains the supporting element labelled 80. With reference also to Figures 4 and 5, the supporting element 80 comprises a body of the device 130 which is supported by the steel lamina 37, which constitutes the conveyor belt 34 and comprises a part 132 above and a part 134 below the lamina connected to each other through a hole, not illustrated in the drawings, made in the lamina 37.

The upper body 132 comprises an outside body and an inside portion 136 for supporting the cover sheet comprising a suitably shaped base 138 with an upper engagement and retaining surface 140 with holes in it designed to create a negative pressure allowing the cover sheet C to be retained by suction.

The base 138 of the inside body 136 is mounted on a stem 137 which extends upwards or outside the edge of the body 132, so as to pick up the cover sheet C from the transfer means 112, as shown in Figure 3.

Similarly, the body forming the recessed supporting elements of the wrapper shell comprise a body 230 having an upper part 232 and a lower part 234 which can be associated with opposite faces of the lamina 37 constituting the conveyor belt 34 and which are also connected to each other through a hole made in the lamina.

This system of supporting and conveying the different parts of the wrapper is very easy to clean. Indeed, there are no intervening spaces or inaccessible gaps where dirt and waste can accumulate. On the contrary, the conveying systems used in prior art machines have a multiplicity of links and joints which make it practically impossible to sanitise the equipment completely.

The passage of the cut cover sheet C from the supporting and transfer means 112 on the revolving wheel driven by the central shaft 111 occurs when the upper surface 118 of the element 112 comes into contact with the upper surface 140 of the mobile body 138 on the outside of the edge of the body 132, and when suction changes from one body to the other, that is to say, when suction is switched off in the transfer head 112 and switched on in the base of the mobile body 138 of the cover sheet supporting element 80.

By keeping the upper surface 118 of the transfer head and the upper surface 140 of the mobile element 138 of the supporting body 80 for a limited angular interval, it is possible for the cover sheet held between the transfer means to be transferred to the supporting and conveying means on the conveyor 34.

During this stage, the wheel 114 is made to turn at the same speed as the conveyor 34 so that the contact surfaces of the elements 112, 118 move at the same tangential speed.

Thus, the wheel 114 is rotated with stop/start motion whereby it is stopped when the cover sheet C is cut and received by one of the transfer heads 112, then started, accelerated and moved at a constant angular speed to enable transfer of the cover sheet and then decelerated when the next head 112 approaches the cutting area and then stops in the position for receiving the next cover sheet C. As shown in particular in Figures 4 and 5, the element 138 for receiving and retaining the cover sheet C protrudes because the supporting body 132 consists of an upper portion 132a and an intermediate supporting portion, both made of plastic, mounted on a base 132c, made of metal, but which might be made of another suitable material, such as plastic for example, and which is fixedly connected to the steel lamina constituting the continuous element of the endless conveyor belt 34 of the machine.

The intermediate portion 132c is fixedly connected to the base 132c, whilst the upper portion 132a is axially mobile relative to the fixed intermediate portion 132b.

More specifically, the upper portion 132a has a cup-shaped body 141 from which a sleeve-like portion 143 with a smaller diameter extends downwardly and fits axially into the cylindrical cavity of a circular wall 145 of the intermediate portion 132b, with an interposed spring, labelled 147 in Figure 4, exerting a pushing action between the transversal surface of an annular shoulder portion 146 of the intermediate portion 132b, which extends radially inwards from the lower edge of the circular wall 145, and the lower transversal surface 141a of the cup-shaped body 141.

Further, the sleeve-like portion has a lower transversal edge 149, that contacts the upper surface of the transversal shoulder portion 146 of the intermediate body 132b, when the latter is pushed downwards, as described in more detail below, causing the base 138 that supports the cover sheet C to protrude outwardly.

To accomplish this downward pushing action at the cover sheet pickup area, cam means are used, which consist of the circumferential cam, schematically illustrated in Figure 4, labelled 150, which acts in conjunction with a wheel 152, attached to the upper body 132a by a pin 154 that fits into a corresponding hole made in a second sleeve 155 located radially on the outside of the first sleeve 143 and is axially guided on the outer cylindrical surface 132 'b of the body 132b.

Both the plastic portions 132a, 132b have an axial hole which accommodates the stem 137 that mounts the cover sheet supporting portion 138. The supporting body 138 and the related stem 137 are made of a plastic material. Plastic is easy to clean in a washing machine, which means the component and hence the conveyor belt can be quickly and easily sanitised. As illustrated, the stem 137 that mounts the base 138 is hollow to enable the passage of suction from a wide chamber 139 that communicates with the outside atmosphere through the holes 142.

Further, the stem 137 has an outside profile that is shaped to match the inside of the intermediate portion 132b in which it is inserted, thus constituting means for radial and axial retention of the cover sheet supporting base 138.

The intermediate portion 132b in turn presents a downwardly protruding sleeve 132"b which slides inside, and in peripheral contact with, a cylindrical receiving body 132d made inside the base 132c, and extends to the other side of the supporting lamina 37 to a point in the proximity of the suction cup 156.

As shown in Figure 5, the hollow stem 137 is wider at its top end, labelled 137a, and narrower at its bottom end, labelled 137b, which extends downwardly and leads into the suction cup 156 which is switched on when the cover sheet is picked up and switched off when the body 80 reaches the top section 34a of the upwardly turning conveyor (see Figure 2) .

At the bottom, between the lower edge of the protruding sleeve 132 "b and an opposing annular shoulder of the portion 132d fixed to the base 132c, there is a spring 158, which, when the body is engaged by the cover sheet pickup means, enables the cover sheet C supporting surface or base 138 to elastically adapt downwardly. Advantageously, for rapidly sanitising this device to remove cheese residue or other waste material, it is possible to dismantle the top of the block 80, that is to say, the parts 134a, 134b, and the cover sheet supporting base 138, together with the related stem 137, which can be placed in a washing machine and substituted by equivalent devices that have already been cleaned, so as to minimise machine downtime. For this purpose, the top part 132a of the supporting block 80 is axially retained downwardly by the lower flanged surface of the base 138, which prevents it from sliding out from above.

To facilitate dismantling of the device, there is a lock pin which is associated with the fixed base 132 and which fits into a matching hole in the protruding sleeve 132"b, passing through the holes 162a in the base 132c and in the cylindrical body 132d.

This pin, labelled 160, has an end 160a which extends to the outside of the base, while its intermediate section passes through an enlarged seat made in said base 132c, this seat being labelled 162 in Figure 4.

As illustrated in Figure 4, the inlet opening 163 of the seat 162 is closed by a bolt-like fastener 164 which is centrally hollow to allow the passage of the pin 160 and which defines, with its outer edge 164a, an annular shoulder which contacts a spring that acts on a radially protruding, annular element 167, and which is associated with the pin 160, so as to push the latter into, and hold it in, the radial hole made in the protruding sleeve of the body 132c. To dismantle device, therefore, it is sufficient to pull the protruding end of the pin 160 outwards against the force of the spring 165 and to slide the top of the body, comprising the parts 132a, 132b, the base 138 and the related stem 137, out of the fixed portion 132c. As illustrated in the drawings, the front end 160' of the pin 160 engages with the outside surface of the portion 137b of the stem 137.

Thus, the cover sheet supporting assembly 132 can be quickly and easily dismantled into its component parts, that is, the cover sheet supporting portions 138, 137, the upper portion 132a and the intermediate portion 132b.

The pin 160 therefore constitutes axial connecting means which are elastically maintained in the engaged condition by the spring 165. To disengage, it is sufficient to pull the end 160a of the pin 160 in a radial direction opposite the action exerted by the spring 165 in order to release the fixed portion 132b and the cover sheet supporting portion 138, which can thus be pulled out of the support. At the same time, the upper portion 132a and the fixed portion 138a can be removed.

As illustrated, according to another aspect, the upper portion 132a of the cover sheet supporting block 80 constitutes means for laterally containing and retaining the cover sheet on the supporting body 132.

Thus, once the cover sheet has been picked up and the cam 150 no longer keeps the upper body 132a in the lowered position, the latter rises and the inside surfaces of its side walls, labelled 170a, 170b, 170c, come into contact with the sides of the cover sheet C in such a way as to create means for laterally retaining the cover sheet. These retaining means make it possible to switch off suction as the cover sheet moves along the horizontal stretch of its travel, thus greatly simplifying the structure of the device.

Thanks to this design suction is not required to keep the cover sheet on the supporting body as it travels all the way to the means that position on the wrapper shell downstream.

In the same way as the cover sheet supporting block 80, the wrapper shell supporting block can also be easily dismantled from its fixed mounting base for quick and effective cleaning and sanitising in an automatic washing machine. The supporting elements are all easy to dismantle, being assembled in quick- release fashion, permitting all the elements to be rapidly substituted and reducing machine downtime to a minimum.

Figures 3 and 6 schematically illustrates the block 35 that supports the wrapper being formed, the structure of this block simpler than that of the cover sheet supporting block 80 and comprising a main body 232a which is mounted on a metal base 232c fixed to the lamina 37 of the conveyor 3 .

The portion 232a of the block 35 consists of a cup-shaped or hollow body with an axial cavity having the shape of a triangle or circular sector, within which a wrapper shell is rested with its underside resting on the bottom of the supporting body. Advantageously, the bottom of this housing 332a for the wrapper shell is axially mobile and consists of a plate 238, mounted on a stem 237, which extends downwardly and has a free bottom end that engages with means, which are not illustrated in the drawings, for driving it in the vertical direction.

The bottom end of the stem 237 passes through, and is supported in an axially slidable manner by, a sleeve 232" that protrudes downwardly from the cup-shaped body 232a and fits into the hole inside the fixed base 232c.

The means for retaining the cup-shaped body 232a consist of a retaining pin, identical to the pin 160 described above, which supports the cup-shaped body in a vertical direction and which is elastically maintained in the engaged condition in exactly the same way as described for the block 80.

For brevity, these means for retaining the block 35 will not be described in detail.

At the lower end of the downwardly protruding sleeve 232" there are axial tabs 232", which can flexibly bend in the radial direction and whose ends present respective teeth 232"d, which extend radially from a lower end portion of this plurality of tabs 232"a, the lower end portion of the tabs protruding downwardly from the sleeve 232" and therefore not being retained by the latter in the radial direction.

To dismantle the block 35 it is necessary to pull the pin, similar to the pin 160 of the block 80, and pull the vertical stem 237 out by the base 238, in such way as to force the lower enlarged portion 237c against the teeth 237d of the retaining tabs 232"a, causing them to bend outwardly in the radial direction and allowing the stem 237 to be pulled out.

It is then possible to pull out the cup-shaped portion 232a which is no longer held in place by the elastic action of the retaining pin similar to that described for the block 80. With reference in particular to Figures 2 and 3, the wheel

36, but the same applies to the wheel 38, for driving the conveyor 34, is engaged by its teeth 36a with the lower portions 134 and 234 of the supporting blocks 80 and 35, each of which has a portion closely facing the base 132c on the opposite side of the lamina 37, whose outer profile is shaped to match the profile of the tooth 36a of the wheel 36. This creates a conveyor belt configuration with engagement and drive means that also constitute means for supporting and connecting the parts supporting the wrapper elements.

The steel lamina 37 thus has suitable width and length, as well as a plurality of longitudinally spaced holes for fixing the bases and engagement elements for the teeth of the drive wheels.

Figures 6 and 7 illustrate the device, labelled 44 in Figure 1, for picking up and applying the cover sheet.

The elements 46 for picking up the cover sheet extend horizontally and are shaped to match the shape of the cover sheet.

They consist of a body with suction holes 170 which lead from the outside surface 172 that holds the cover sheet to an inside chamber 174 connected to suction means through suitable conduits.

The blocks 46 are mounted on a longitudinal element or base plate L, which supports longitudinally two cover sheet pickup blocks and transversally a number equal to the rows of wrapper shells, preferably, as in this case, two rows of wrappers.

This device makes it possible, by keeping the longitudinal element L parallel to the feed belt, to lower the blocks 46 into contact with the cover sheet C and its support 138, by compressing the spring 158, while the block 80 continues to move, then to raise the blocks 46, causing them to move back and then down again so that the blocks and the cover sheets on them are carried to the blocks 35 that follow, each of which has a wrapper shell V on it, which has already been filled with processed cheese, and finally, to position the cover sheet C on the top surface of the product inside the wrapper shell V.

During the final positioning step, the means for engaging and driving the cover sheet C pickup and delivery block follows the linear motion of the block 35 so that, when the suction through the holes 170 is switched off, the cover sheet C is released onto the wrapper shell to close the top of the wrapper.

As shown in Figure 7, the longitudinal base plate L supporting the elements 46 has blades 49 on it for keeping the top flaps of the wrapper side walls apart to prevent them from interfering with the positioning of the cover sheet on the top of the product inside the wrapper shell. The blades 49, which are pivoted at point 49', are designed to keep the flaps at the heel end of the wrapper apart. There are other lateral blades, which are not illustrated in the drawings, pivoted to the base plate L for keeping the other side walls of the wrappers apart. The suction element 46 for picking up and releasing the cover sheets is mounted on the end of a shaft 47 which slides vertically relative to the base plate L. In practice, during a first step, the base plate L moves down towards the wrapper shell, carrying the blades 49 into contact with the upper flaps of the wrapper shell extending past the edge of the product inside the wrapper. The blades are then rotated in such a way as to move wrapper flaps apart. At this point, the shaft 47 moves down relative to the base plate L and carries the suction element 46 to the cover sheet release position. During the downward movement, the blades 49 act as guides helping to centre the cover sheet on the suction element 46. All these operations are carried out while the base plate L moves in a horizontal direction parallel to the belt 34 carrying the wrappers.

A similar operation is contemplates for picking up the cover sheets from the respective support 80. During this step, however, as shown in Figure 6, the blades 49 are kept apart on the outside so as not to interfere with the cover sheet pickup operation.

Figure 8 shows the advantageous configuration of the means for driving the elements 46, 46 of the device for picking up and positioning the cover sheets, as well as those of the other devices, labelled 42, 50, 60, 62 which drive, respectively, the product dispensing nozzles 40, the elements 52 for folding the wrapper flaps over the cover sheet already positioned by the means 48, the sealing elements 58, and the outfeed or transfer paddles 66.

Like the product dispensing means 42, the means 50 for folding the wrapper flaps over the cover sheets, the means 60 for sealing the cover sheets and the means 62 for laterally moving the wrapped product, the present means for applying the cover sheets over the full wrapper shells comprise, as shown in Figure 8, a horizontal longitudinal element or base plate L, which is only schematically illustrated and which mounts a plurality of working elements 46, arranged in respective longitudinal and transversal rows. In this particular embodiment, there are two longitudinal rows and two transversal rows (making a total of four cover sheet application elements 46) . Obviously, each of the base plates of the other working parts of the machine are designed to mount four working elements 52, 58, 66, arranged in the same way, with the exception of the base plate of the product dispensing nozzles 40 which mounts two longitudinal rows of nozzles 40 but four transversal rows of nozzles 40, making a total of eight nozzles for simultaneously filling eight wrappers, whilst the other parts simultaneously operate on only four wrappers.

The invention -thus contemplates the provision of means for driving the parts 40, 46, 52, 58, 66 that operate on the wrapper, said means comprising the longitudinal base plate L, which is designed to mount a plurality of working parts and means for driving the base plate L along longitudinal forward and return movements, where the forward movement at least partly includes the working stroke of the parts operating on the wrappers, at least a section of said working stroke being substantially horizontal and parallel to the path followed by the wrappers.

More specifically, the means for driving the base plate L comprise means for driving or oscillating through an angular interval, and means for compensating the movement imparted by the first drive means, in such manner that the working parts 46 (and the other similar parts) mounted on the longitudinal base plate L are made to follow a substantially horizontal path parallel to the path followed by the wrappers being formed.

Moreover, the first drive means and the second drive (or compensation) means cause the base plate L to perform an arc- shaped return stroke at a height above the level where the forward, working stroke of the working parts is performed.

Advantageously, the means for driving the base plate L are designed to keep the base plate oriented in the same direction which, in the present embodiment of the invention, is a horizontal direction.

As shown in Figure 8, the base plate L is associated with connecting rods Bl, B2 pivoted on each side of the base plate L through suitable hinges essentially comprising hinge pins Cl and C2.

At their upper opposite ends, the connecting rods Bl, B2 are pivoted, through hinges constituted by respective shafts C3, C4, to circular plates attached to central shafts Al, A2, which impart on the circular plates an oscillating motion such that they travel through angular forward and return strokes, as indicated by the arrows FR1 and FR2 in Figure 8.

In practice, the means for driving the base plate L comprise first and second connecting rods Bl, B2 hinged at their lower ends to the ends of the base plate L. At their top ends, the first and second connecting rods Bl, B2, are connected to and supported by respective shafts C3, C4 which are rotationally driven along arc- shaped paths by respective rotary plates or discs PI, P2, to which they are connected in such a way that they can rotate freely so as to keep the base plate oriented horizontally. The free rotational connection of the connecting rods Bl and B2 relative to the discs PI and P2 is achieved thanks to the fact that the pin C4 passes through a corresponding hole (not shown in the drawing) of the corresponding disc P2, while the connecting rod Bl is connected in freely rotatable manner to the respective mounting shaft C3.

Means are provided for driving the discs PI and P2 to perform forward and return angular movements of predetermined extent. These means are not illustrated in detail and may be of any type well known to experts in the trade. In Figure 8, these means are schematically illustrated and labelled MR. The angular oscillation means MR acting on the shafts Al and A2 simultaneously rotate the drive discs or plates PI and P2.

Means are also provided for oscillating the connecting rods Bl, B2 in the direction indicated by the angular arrows FC1 and FC2, so that, during the working strokes of the working parts acting on the wrappers, the vertical movements of the hinge shafts C3, C4 are compensated and the base plate L moves along a horizontal path at the same height as the wrappers. More specifically, the oscillating, vertical compensation movement is accomplished by rotational drive means MO which act on an extension of the pin C4 attached to connecting rod B2 in such a way as to drive the connecting rod B2 according to an oscillating path FC2. The other connecting rod, being connected in a freely rotatable manner to the shaft C3, is driven along with it according to a corresponding oscillating path FC1, thanks to the four-point linkage type connection created by the base plate L.

As shown also in Figure 1, the plates PI and P2 are mounted in corresponding circular openings 01, 02 made in the longitudinal partition wall I in the machine, extending vertically and longitudinally and separating the working area of the machine where the wrappers are formed by the working parts described above from the mechanisms that drive these working parts.

Advantageously, as illustrated in Figure 8, between the circular surfaces defining the openings 01, 02 made in the partition wall I and the outer edges Dl, D2 of the circular plates PI, P2, there are circumferential seals Gl, G2, which completely isolate the wrapping area from the drive area of the machine without obstructing the rotational motion of the rotary discs or plates PI, P2.

It can also be seen that the shafts C3, C4 mounting the connecting rods Bl, B2 project from the longitudinal partition wall I of the frame (or from the discs Pi, P2) by a defined length, thus constituting means for transversely positioning the working parts relative to the wrappers which the working parts operate on. Thanks to the four-point linkage type drive mechanism formed by the base plate L, drive is extremely "clean" and there is no risk of contamination of the food product by the working parts that operate on the wrappers .

As illustrated, the present embodiment of the machine advantageously comprises means for separating the drive area (motors, and transmission and drive mechanisms) from the wrapper forming area. These separation means consist essentially of the partition wall I which extends along the full length of the machine. The partition wall I is vertical and its height is preferably the same as that of the machine. As illustrated, the separation advantageously further comprise mobile surfaces PI, P2, from which there extend the shafts C3, C4 which mount and drive the working parts that operate on the wrappers. The mobile surfaces also constitute means for driving the working parts.

To further facilitate the sanitising procedure in the machine according to the invention, the unit that dispenses or feeds the food product can be disconnected from the rest of the machine. This unit is associated with an independent frame 12a mounted on swivelling wheels W which enable it to be easily moved to another part of the production facility for washing. Obviously, suitable means are provided for easily connecting and disconnecting the independent part of the 12a to and from the min body of the frame 12.

According to the present preferred embodiment, the components mounted on the independent frame 12a comprise means for connecting to pipes for feeding the food product, but which might also be equipped with a tank or hopper for the food product, a metering unit, pipes connecting the metering unit to the dispensing nozzles, pipes connecting the product tank to the metering unit, a longitudinal partition wall I' and means for driving the nozzles 40. It will be understood that the invention can be adapted and varied in several ways without thereby departing from the scope of the inventive concept. Moreover, all the details of the invention may be substituted by technically equivalent elements.

Claims

1. A machine for wrapping a pasty, liquid or semi-liquid product, and in particular, a processed cheese or similar product; where the wrapper is made from a flat sheet that is folded to form a shell-like body or container whose top is then covered over; the machine comprising a mounting frame (12), working means for forming the wrappers and means for driving the working means, the machine being characterised in that it further comprises separating means (I, PI, P2) at least between the drive area and the wrapper forming area.

2. The machine according to claim 1, characterised in that the separating means comprise a wall (I) which extends in the lengthways direction of the machine.

3. The machine according to claim 1 or 2, characterised in that the separating means comprise at least one mobile surface (PI, P2) from which there extend shafts (C3, C4) which mount and drive the working parts that operate on the wrappers.

4. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it comprises means for driving the parts (40, 46, 52, 58, 66) that operate on the wrapper, said means comprising a longitudinal base plate (L) , which is designed to mount a plurality of working parts

(40, 40 or 46, 46 or 52, 52 or 58,58 or 66, 66) and means for driving the base plate (L) along longitudinal forward and return movements, where the forward movement at least partly includes the working stroke of the parts operating on the wrappers, at least a section of said working stroke being substantially horizontal and parallel to the path followed by the wrappers.

5. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it comprises means for driving the parts (40, 46, 52, 58, 66) that operate on the wrapper, said means comprising a longitudinal base plate (L) , the means for driving the base plate (L) comprising first drive means (PI, P2 ) and means (Bl, B2) for compensating the movement imparted by the first drive means, in such manner that the working parts mounted on the longitudinal base plate (L) are made to follow a substantially horizontal path parallel to the path followed by the wrappers.

6. The machine according to claim 4 or 5, characterised in that the means for driving the base plate (L) are designed to keep the base plate oriented in the same direction, that is to say, in a horizontal direction.

7. The machine according to any of the foregoing claims from 4 to 6, characterised in that the means the means for driving the base plate (L) comprise first and second connecting rods (Bl, B2) hinged to the base plate (L) , the first and second connecting rods (Bl, B2) being supported by respective shaft (C3, C4) rotationally driven along circumferential paths by respective rotary discs (PI, P2) to which they are connected in a freely rotatable manner so as to keep the base plate oriented horizontally; further means being also provided for oscillating the rotary discs and for oscillating the connecting rods in such a way that, during the working strokes of the working parts acting on the wrappers, the vertical movements of the hinge shafts (C3, C4 ) are compensated and the base plate (L) moves along a horizontal path at the same height as the wrappers.

8. The machine according to claim 7, characterised in that the oscillating, vertical compensation movement is accomplished by driving the connecting rod (B2) according to an oscillating path (FC2), while the other connecting rod (Bl), being connected in freely rotatable manner to the respective mounting shaft (C3), is driven along with it according to a corresponding oscillating path (FC1) thanks to the base plate (L) .

9. The machine according to claim 7 or 8, characterised in that the circular plates (PI, P2) are mounted in corresponding circular openings (01, 02) made in the longitudinal partition wall (I) in the machine.

10. The machine according to claim 9, characterised in that, between the circular surfaces defining the openings (01, 02) made in the partition wall (I) and the outer edges (Dl, D2) of the circular plates (PI, P2), there are circumferential seals (Gl, G2) .

11. The machine according to any of the foregoing claims from 7 to 10, characterised in that the shafts (C3, C4 ) mounting the connecting rods (Bl, B2) project from the longitudinal partition wall (I) of the frame.

12. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it further comprises means for dispensing or feeding the food product mounted on an independent frame (12a) which enables said means to be disconnected from the rest of the machine.

13. The machine according to claim 12, characterised in that the independent frame (12a) is mounted on means (W) which enable it to be moved.

14. The machine according to claim 13, characterised in that the independent frame (12a) is mounted on wheels (W) which enable it to be moved.

15. The machine according to any of the foregoing claims from 12 to 14, characterised in that the independent frame (12a) is separably connected to the main frame.

16. The machine according to any of the foregoing claims from 12 to 15, characterised in that the independent frame (12a) mounts a corresponding partition wall (I').

17. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it comprises feed means in the form of a flat flexible lamina (37) that supports a plurality of longitudinally spaced supporting elements .

18. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it further comprises blocks (80) for supporting the wrapper cover sheets and/or blocks (35) for supporting the wrapper shells, said blocks being separably connected to the conveyor (34) and in particular to the continuous longitudinal drive means (37) of the conveyor.

19. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it comprises a block (35) for supporting the wrapper being formed and comprising a main body (232a) mounted on a base (232c) fixed to the conveyor (34).

20. The machine according to claim 19, characterised in that the base (232c) is fixed to the lamina (37) of the conveyor (34).

21. The machine according to claim 19 or 20, characterised in that the main portion (232a) of the block (35) consists of a cup- shaped or hollow body with an axial cavity of suitable shape, within which a wrapper shell is rested with its underside resting on the bottom of the supporting body.

22. The machine according to any of the foregoing claims from 19 to 21, characterised in that the bottom of the bottom of this housing (232a) for the wrapper shell is axially mobile.

23. The machine according to any of the foregoing claims from 19 to 22, characterised in that the bottom of this housing (232a) for the wrapper shell is axially mobile and consists of a plate (238), mounted on a stem (237) which extends downwardly and has a free bottom end that engages with means for driving it in the vertical direction.

24. The machine according to any of the foregoing claims from 19 to 23, characterised in that the bottom end of the drive stem

(237) passes through, and is supported in an axially slidable manner by, a sleeve (232") that protrudes downwardly from the cup- shaped body (232a) and fits into the hole inside the fixed base (232c) .

25. The machine according to any of the foregoing claims from 19 to 24, characterised in that it comprises means for retaining the cup-shaped body (232a) , said means consisting of a pin for engagement and retention in an axial direction.

26. The machine according to any of the foregoing claims from 19 to 25, characterised in that, at the lower end of the downwardly protruding sleeve (232") there are axial tabs (232"), which are flexibly yielding in the radial direction and whose ends present respective teeth (232"d) , which extend radially from a lower end portion of this plurality of tabs (232"a) , the lower end portion of the tabs protruding downwardly from the sleeve (232") and not being retained by the latter in the radial direction.

27. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it further comprises wrapper cover sheet supporting blocks (80) carried by a respective conveyor belt of the wrapper sheets.

28. The machine according to claim 27, characterised in that the cover sheet supporting block (80) comprises a fixed lower body (132b) which supports the hollow upper body (132a) that slides vertically over it and that is separably connected to the conveyor (34) .

29. The machine according to claim 28, characterised in that the fixed lower body (132b) is separably connected to a base (132c) protruding from the longitudinal lamina (37) of the conveyor (34).

30. The machine according to any of the foregoing claims from 27 to 29, characterised in that it comprises means (160) for retaining the fixed lower body (132b) which are elastically maintained in the engaged condition, and in that it also comprises means (160a) for operating the retaining means in such a way as to disengage the fixed body (132b) .

31. The machine according to claim 30, characterised in that the means for retaining the fixed body (132b) comprise a pin (160) which can be inserted in the base (132c) attached to the conveyor (34), and which has one end for engaging and retaining the fixed lower body (132b) and another end (160a) that can be operated to disengage it.

32. The machine according to any of the foregoing claims from 27 to 31, characterised in that the cover sheet supporting block (80) comprises a fixed lower body (132b) which supports the hollow upper body (132a) that slides vertically over it and that is separably connected to the conveyor (34).

33. The machine according to any of the foregoing claims from 27 to 32, characterised in that the fixed lower body (132b) is separably connected to a base (132c) protruding from the longitudinal lamina (37) of the conveyor (34).

34. The machine according to any of the foregoing claims from 27 to 33, characterised in that it comprises means (160) for retaining the fixed lower body (132b) which are elastically maintained in the engaged condition, and in that it also comprises means (160a) for operating the retaining means in such a way as to disengage the fixed body (132b) .

35. The machine according to claim 34, characterised in that the means for retaining the fixed body (132b) comprise a pin (160) which can be inserted in the base (132c) attached to the conveyor (34), and which has one end for engaging and retaining the fixed lower body (132b) and another end (160a) that can be operated to disengage it.

36. The machine according to any of the foregoing claims from 27 to 35, characterised in that it comprises means (160) for retaining the upper body (132a) constituting the means for laterally retaining the cover sheet.

37. The machine according to claim 36, characterised in that the means (160) for retaining the upper body (132a), constituting the means for laterally retaining the cover sheet, comprise a block (138) for supporting the cover sheet and which has a wide shape that impinges on a corresponding portion of the upper body (132a) .

38. The machine according to any of the foregoing claims from 27 to 37, characterised in that it comprises elastic means (147) for keeping the upper body in normal extended position.

39. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that the means for feeding the wrappers comprise engagement and drive means that constitute means for supporting and connecting the parts supporting the wrapper elements.

40. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it comprises means (70) for cutting the cover sheets (C) , located well away from the means (39) for filling the product into the wrapper shell.

41. The machine according to claim 40, characterised in that the means (70) for cutting the cover sheet (C) are located well away from and upstream of the means (39) for filling the product into the wrapper shell.

42. The machine according to claim 40 or 41, characterised in that the means for cutting the cover sheet (C) are located well away from and at a position (38) upstream of the means for forming the wrapper.

43. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it comprises at least one partition (84) separating the product dispensing means (39) from the means (14, 16, 70) for cutting the wrapping materials.

44. The machine according to claim 43, characterised in that the partition (84) is located between the wrapper shell folding area and the product dispensing area.

45. The machine according to claim 43 or 44, characterised in that the partition (84) has an opening to allow the passage of the wrapper shell feed means (35) .

46. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it comprises means (34, 80) for feeding and conveying the cover sheets (C) to the area where the cover sheets are applied.

47. The machine according to claim 46, characterised in that it the means for feeding the cover sheets comprise the conveyor (34) which also feeds the wrapper sheets.

48. The machine according to claim 47, characterised in that it comprises wrapper cover sheet supporting blocks (80) , supported by a respective conveyor belt of the wrapper sheets.

49. The machine according to any of the foregoing claims, characterised in that it comprises means (70) for cutting the cover sheets (C) , acting with stop/start motion on cover sheet contact and retaining means (112).

50. The machine according to claim 49, characterised in that it comprises means (76) which, after receiving the cover sheets when the cutting means (70) stop, transfer them to the sheet feed means while the latter are in motion.

51. The machine according to claim 50, characterised in that the transfer means (76) comprise a plurality of cover sheet retaining heads (112) located at regular intervals on the transfer means.

52. The machine according to claim 50 or 51, characterised in that the means (76) for transferring the cover sheets present means for retaining the cover sheets during transfer of the latter to the position where they are delivered to their respective supports .

53. The machine according to any of the foregoing claims from 50 to 52, characterised in that cover sheet transfer means consist of a revolving element with a plurality of pickup elements mounted on it at regular predetermined angular intervals.

54. The machine according to any of the foregoing claims from 50 to 53, characterised in that the cover sheets are delivered to the respective supports (80) at a point in time between the moment one pickup element (112) reaches the cover sheet cutting means and the moment the next pickup element reaches the same cutting means.

55. The machine according to any of the foregoing claims from 50 to 54, characterised in that the elements (80) for supporting the cover sheets present means for retaining the cover sheets while the latter are being picked up by the transfer means (76) .

56. The machine according to any of the foregoing claims from 27 to 55, characterised in that the elements (80) for supporting the cover sheets present means for retaining the cover sheets while the latter are being conveyed to the area where they are applied to the wrapper shell.

57. The machine according to claim 56, characterised in that the retaining means comprise lateral surfaces (170a, 170b, 170c) which extend past the cover sheet supporting base.

58. The machine according to any of the foregoing claims from 50 to 57, characterised in that, while the cover sheets are being picked up by the transfer means (76) , the surface that supports the cover sheet extends past the upper edge of the lateral surfaces (170a, 170b, 170c) that contain the cover sheet.

59. The machine according to any of the foregoing claims from 27 to 58, characterised in that the cover sheet support comprises an upper body (132a), which defines the lateral surfaces (170a, 170b, 170c) containing the cover sheet and which is axially mobile relative to the base (138) for supporting the cover sheet; means being provided for lowering the upper body (132a) relative to the cover sheet supporting base (138) when the cover sheet is passed to the supporting means.

60. The machine according to any of the foregoing claims from 27 to 59, characterised in that the cover sheet supporting base (138) has a spring acting axially in order to soften the impact with the cover sheet pickup elements (46).

61. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it comprises cover sheet application means (48) that pick up the cover sheet from the respective support to place it on a wrapper shell which has been filled with product and which is carried on a respective support, the application means (48) picking up the cover sheet located on the support immediately preceding the one on which the wrapper shell which it is to be placed on is located.

62. The machine according to claim 61, characterised in that the cover sheet application means (48) comprise drive means for lowering the blocks (46) into contact with the cover sheet (C) and its support (138) while the latter moves forward, then raising the blocks (46), causing them to move back and then down again so that the blocks (46) and the cover sheets on them are carried to the block (35) that follows, which has a wrapper shell on it, and following the feed motion of the block (35) that follows so as to enable the cover sheet to be placed on that wrapper shell.

63. The machine according to any of the foregoing claims, characterised in that the means for retaining the cover sheets on the transfer means (76) and/or on the feed support (80) are suction means.

64. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that the means (70) for cutting the cover sheets are located under the means (32) for transferring the wrapper sheets from the area where the wrapper sheets are prepared to the area where the wrapper shells are formed.

65. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that it comprises means (14) for cutting the wrapper sheets from a web of wrapper material are mounted at an end (Tl) of the machine.

66. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that the means for cutting the cover sheets are mounted at a level below the level where the food product is filled into the wrapper shells .

67. The machine according to any of the foregoing claims or according to the preamble to claim 1, characterised in that the machine extends mainly in a longitudinal direction.

68. The machine according to any of the foregoing claims, characterised in that it comprises at least one of the following: means (14, 16) for cutting the wrapper sheets from a respective web of material; means for preparing the cover sheets (C) including means (70) for cutting the sheets (C) from a respective web (74) of material (72); means (38) for folding each wrapper sheet to form a shell; means (39) for filling the product into the shell; and means for closing the shell including means (48) for placing over the shell a corresponding cover sheet cut by the cutting means (70) .

69. A device for driving the working parts (40, 46, 52, 58, 66) operating on the wrapper of a respective product, characterised in that it is made in accordance with any of the foregoing claims from 4 to 11.