Process and machine for packing

Abstract

A load is wrapped in a length of film approximately corresponding to a periphery of the load. The film emanates from a stack reel, and is wound onto a transfer magazine. This magazine is then moved relative to the load, around the same, to form a loop of film around the load. The film is unwound from the magazine in this process. Finally the ends of the loop are joined, edge to edge.

Description

The invention relates to a process and a machine for packing, by the aid of one single intermediate transfer support of elongated shape, such as a cylinder or a prism.

A packing process and machine are known in which a curtain of packing film is first of all produced between two horizontal or vertical stock reels. The load to be packed is then moved in the direction of the curtain, which undergoes deformation due to the load and comes to rest against this latter. The two parts of the film are then combined together along two horizontal or vertical lines, both sides of the load.

Another known type of packing machine comprises a table which is mounted pivotably about a vertical axis and on which is placed the load to be packed, on the one hand, and a vertical stock reel of film, on the other. During the pivoting movement of the table, the film, of which the initial end is taken up by the load, comes to rest little by little against the latter, in order to cover it.

Finally, a packing machine is known which comprises one single stock and transfer reel of which the shaft can be adjusted in its position around the load to be packed. The initial end of the film is hooked into the load, and this film gradually covers the load as and when the shaft of the reel continues in its movement around the latter.

These various types of machine all suffer from the dual drawback that the load actively participates in the packing process, which may prove inconvenient, particularly in the case of fragile loads, and that is is difficult to use them with types of film capable of stretching.

Finally, in the particular case of a machine of the "curtain" type, the packing process involves two lines along which the film is to be joined, these being in the front and at the rear of the load respectively and constituting extra-fragile zones in which the packing is more than usually liable to deteriorate.

The purpose of the packing process and machine to which the invention relates is to remedy these various drawbacks by the use of one single horizontal or vertical stock reel for film, its dimension (width, thickness, etc.) and nature being easily and automatically adaptable to the load to be packed. The process and the machine can be employed with films capable of stretching.

A process enabling a load held in a fixed position to be packed in a film of material emanating from one single stock reel with a vertical shaft is preferably characterized by the fact that a length of film approximately corresponding to the periphery of the load to be packed is wound onto a cylindrical transfer magazine with a vertical shaft, after which the said cylindrical magazine is moved around the load and starting from a point in the vicinity of the stock reel in order to cause it to form a loop around the load, the length of film stored in advance on the cylindrical magazine being progressively unwound in the course of the said movement in order to apply the film to the load, the two ends of the film then being joined edge to edge.

A process for packing a load from one single film wound onto a stock reel with a horizontal shaft and situated above the load is characterized by the fact that a length of film sufficient to cover the load, i.e. a length at least equal to the perimeter of the load to be covered, is unwound from the stock reel, a vertical curtain kept stretched in front of the load being formed with the film which has been unwound, the load being moved horizontally in the direction of the curtain, thus deforming the latter, in such a way as to apply the film first to its vertical front surface and then to its upper and lower horizontal surfaces, using the unwound film, the film being applied to the rear vertical surface of the load in order to form a loop of film completely surrounding the said load, after which the two ends of the said loop are joined together.

A machine for packing a load in one single film emanating from a stock reel with a horizontal or vertical shaft situated in the upper part of the machine, the machine being intended in particular for a goods handling line, is characterized by the fact that it comprises one single cylinder of which the axis is parallel to that of the stock reel and which is fitted with means for winding onto it the film emanating from this latter, the said cylinder being movable in accordance with a given kinetic circuit, which is adapted in such a way as to ensure that the axis of the cylinder is kept parallel to the reel at all times and that the film attached by one of its ends to the cylinder will progressively form a loop completely surrounding the load.

The invention will be understood more clearly from the description given of a number of embodiments thereof, by reference to the drawings, in which:

FIGS. 1, 2 and 3 are three schematic views from above, illustrating respectively an initial stage, an intermediate stage and the final stage of the process to which the invention relates, in the case of a vertical stock reel.

FIG. 4 is a view, from above, of a first embodiment of the packing machine, with a vertical stock reel.

FIG. 5 is a half-section, through a vertical axial plane, of another embodiment of a machine with a vertical stock reel.

FIG. 6 is a view, in elevation, of a control board for the movements of a cylindrical transfer magazine for the machine shown in FIGS. 4 and 5.

FIG. 7 is a view, from above, of a second possible alternative version of the packing machine with a vertical stock reel.

FIG. 8 is a view, from above, of a third possible version of the packing machine with a vertical stock reel.

FIG. 9 is a schematic sectional view through a vertical central plane, illustrating a packing machine with horizontal reels.

FIGS. 10-16 are partial sectional schematic diagrams, through a vertical central plane, illustrating the successive operating phases of the machine shown in FIG. 9.

FIG. 17 is a schematic diagram, in perspective, illustrating the means for driving a transfer cylinder for the machine shown in FIG. 9.

FIGS. 18-23 are schematic sectional diagrams through a vertical central plane, illustrating a first alternative version of a machine with a horizontal stock reel, at six different stages of its operation.

FIGS. 24 and 25 are schematic section diagrams, through a vertical central plane, illustrating a second alternative version of a machine with a horizontal stock reel, at two stages of its operation.

FIGS. 26 and 27 are schematic sectional diagrams, through a vertical central plane, illustrating a third alternative version of a machine with a horizontal stock reel, at two different stages of its operation.

FIGS. 28-30 are schematic sectional diagrams, through a vertical central plane, illustrating a fourth possible alternative version of a machine with a horizontal stock reel, at three different stages of its operation.

FIGS. 31-33 are schematic sectional views, through a vertical central plane, illustrating a fifth possible alternative version of a machine with horizontal stock reel, at three different stages of its operation.

FIGS. 1 - 3 show a load 1 which is held in a fixed position and of which the vertical lateral faces are to be covered with a film of material emanating from a stock reel 2 with a fixed vertical shaft. The packing is carried out by the combined movements of an intermediate transfer support consisting, in this particular case, of a cylindrical magazine 3 movable abouts its vertical pivot 4, capable of moving along a circuit 5, forming a loop surrounding the load 1.

In the first stage of the process the pivot 4 is kept in a fixed position and the cylindrical magazine 3 caused to rotate about its pivot 4 in the direction shown by the arrow 6, as a result of which a length of film, approximately corresponding to the peripheral length of the load 1 to be packed, accumulates on the said magazine. The stock reel 2 can pivot about its vertical pivot, preferably with moderate friction, in order to prevent the film from unwinding too suddenly (FIG. 1).

In the second stage of the process, the stock reel 2 is secured in position on its pivot while at the same the shaft 4 of the cylindrical magazine is caused to move along the circuit 5 from its initial position (FIG. 1) in the direction shown by the arrow 7 and the said magazine 3 also turns about its pivot 4 in that shown by the arrow 8 and opposite to that shown by the arrow 6. These two combined movements, i.e. the rotation of the cylindrical magazine about its axis and the displacement of the shaft of the cylinder, result in the unwinding of the film which has accumulated in advance on the cylindrical magazine and in the gradual covering of the lateral faces of the load 1.

These combined movements are continued until the cylindrical magazine 3 has largely returned to its initial position in the vicinity of the stock reel 2 and the film 9 forms a closed loop totally covering the vertical laterial faces of the load 1 (FIG. 3).

The next operations are the joining of the two ends and of the loop of film 9 and the cutting of the said film, represented schematically by the arrows 10a and 10b. The load 1 can then be removed and a fresh packing cycle commenced. The operation of joining together the two ends of the film is carried out by any known process (welding, adhesive, hooks etc.).

In a possible alternative version of the process the film emerges above the upper horizontal face of the load 1, and this emerging part is folded over onto the load insuch a way as to cover it. A sheet joined to the band previously produced can likewise be pressed against the said upper horizontal face.

In another version of the invention use can be made of a film capable of stretching.

The stretching can be effected by braking the rotation of the cylindrical magazine 3 about its shaft 4 during its movement along the circuit 5. The film stored on the cylindrical magazine not being stretched, the stretching is applied to the corners of the load.

The stretching can also be effected by creating a tension on the film at the moment when it is stored on the cylindrical magazine. This tension results either from the braking of the stock reel 2 in rotation about its shaft or from the linear speed difference between the stock reel 2 and the magazine 3. In both cases the force applied to the load 1 is much smaller than in the first version described above.

FIG. 4 shows a possible embodiment of the machine comprising a central pallet 10 on which is placed the load to be covered, two concentric toothed rims, i.e. an internal one 11 and an external one 12, of which the teeth, facing toward the external one 12 and towards the internal one, respectively, engage a pinion 13 integral with the shaft 4 of the cylindrical magazine 3 and situated between the two toothed rims.

Driving means 14 and 15 in the form of reduction motors, for example, drive the internal toothed rim 11 and the external toothed rim 12 respectively, causing them to rotate about their common pivot 16.

The stopping or operation, in the direct or indirect sense, of each of the reduction motors 14 and 15, and thus of the toothed rims 11 and 12 associated therewith, define the possibilities for the movement of the cylindrical magazine 3. The nine combined possibilities of movement for the shaft 4 of the cylindrical magazine 3 on the one hand and the cylinder 3 turning about its pivot 4 on the other are indicated in their turn in FIG. 6 as a function of the direction of movement imparted to each of the reduction motors 14, 15. Each of these latter is either at a standstill, represented by 0, in direct rotation, shown by +, or in indirect rotation, shown by -. The movement of the shaft 3, if any, is shown either by the arrow V + or by the arrow V -, according to whether it is direct or indirection. Similarly, the rotation of the cylinder 3 about its pivot 4, if any, is shown either by the arrow U+ or by the arrow U-, according to whether is it direct or indirect.

The machine according to the invention may comprise a double input control board, each input comprising three push buttons, i.e. for stopping the reduction motor 14 and 15 and for operating them in either of the two directions.

Finally, the machine incudes a stock reel 2 situated outside the external toothed rim 12. This stock reel is preferably mounted with moderate friction on its vertical shaft in such a way as to obviate any over-sudden unwinding of the film.

FIG. 5 shows a first embodiment of the machine with vertical stock reel, comprising a cylindrical drum 17 capable of turning about its vertical pivot 16 and provided on its cylindrical surface with at least one internal chain 18, and also a collar 19, of the same axis as the drum 17, these two items being rotatable about the said axis, enveloping the drum 17, the collar being provided on its internal face with at least one external chain 20, the said chains, i.e. the internal chain 18 and the external chain 20, engaging the pinion 13 of the cylindrical magazine 3. The internal chain 18 and the external chain 20 drive the shaft 4 of the cylindrical magazine and/or the cylindrical magazine 3 itself, pivotable about its shaft 4. The collar 20 may comprise a bent part 21 forming a support for the pinion 13 of the cylindrical magazine 3, which is thus suspended and guided by the drum 17 and the collar 19.

In one possible alternative the two movements of the cylindrical magazine 3 can be separate. In this case, the packing machine comprises a supplementary reduction motor causing the cylindrical magazine 3 to turn about its pivot 4 at the moment when the film coming from the stock reel 2 accumulates. The said magazine is in this case mounted with moderate friction on its shaft 4 in such a way that during the movement of this shaft the film subjects the cylinder to a certain tension causing it to perform a pivoting movement.

FIG. 7 shows a second variant of the packing machine with vertical stock reel. This version comprises two rectilinear gantries 22, 23, which are parallel to each other and situated on the respective sides of the load 1, forming horizontal slide bars between which a traverse 24 extends and is able to slide.

One or more assemblies comprising a reduction motor 25, an endless chain 26 and a toothed return wheel 27 enables the traverse 24 to be moved along the gantries 22 and 23 forming slide bars.

The cylindrical magazine 3 is borne by a carriage 28 slidably mounted on the traverse 24 and driven in a manner known per se by a reduction motor 29, an endless chain 30 and a toothed return wheel 31. The stock reel 2 is preferably situated in the vicinity of an edge of the gantry, such as that of the gantry 22.

The circuit 5 is of square or rectangular shape, defined by the four apices a, b, c, d. During the movement of the pivot 4 of the cylinder 3 over the sections ab and cd, the carriage 28 moves in one direction or in the other along the traverse 24, which remains at rest. On the other hand, during the movement along the sections bc and da, the carriage 28 remains in a fixed position on the traverse 24, which is moved in one direction or in the other along the gantries 22 and 23 forming slide bars.

In this second variant, the cylindrical magazine 3 is preferably mounted with moderate friction in such a way that the movement of this carriage or that of the traverse 24 causes the cylinder to turn about its pivot as a result of the tension exerted by the film.

Needless to say, this variant comprises, as before, means for cutting and combining the ends of the film. These means, known per se, extend vertically in the vicinity of the stock reel. They consist of welding jaws, gripping devices, adhesive devices or any other suitable means.

FIG. 8 shows a third possible variant of the machine with vertical stock reel, comprising a horizontal square or rectangular closed ring defining the circuit 5, the cylinder 3 being suspended thereon. Jacks 33a, 33b, 33c and 33d are situated at the respective corners a, b, c and d of the slide bars 32, parallel to the sides ab, bc, cd, da. The jack 33a, the jack 33b, the jack 33c and the jack 33d are actuated respectively in succession when the cylindrical magazine is situated at the corner a, at the corner b, at the corner c, or at the corner d. The cylindrical magazine is mounted with moderate friction about its shaft in such a way that the movement the said shaft 4 causes the film to be unwound from the cylinder.

If use is made of a film capable of stretching, the machine can comprise, in a first possible version, a device for braking the pivoting movement of the stock reel 2.

In a second possible version, the stock reel 2 and the cylindrical magazine 3 both engage an intermediate pinion having a wide first driving rim engaging the cylindrical magazine 3 and a second, narrower driving rim, engaging the stock reel 2.

In a third possible version, the cylindridal magazine 3 and the stock reel are set in rotation in such a way that their linear pierpheral speeds differ.

Needless to say, the machines described in the foregoing may be improved of varied in numerous ways, within the scope of the invention. In particular, the cylindrical magazine serving as a transfer device can be replaced by a prism or any other elongated device with a longitudinal axis of symmetry.

The packing process and machine can also be applied to horizontal stock reels. A description will now be given of various versions of the process and of the corresponding machines.

The process for the packing of a load, starting from one single film of material, wound onto a stock reel with a horizontal shaft, comprises the following successive stages: first of all a length of film sufficient to cover the load is unwound from the stock reel, i.e. a length at least equal to the perimeter of the load to be covered. A vertical curtain is them formed with the unwound film and kept stretched in front of the load. The load is then moved horizontally in the direction of the curtain, thus subjecting the latter to deformation and consequently causing the film to come to rest against the front surface of the load and then its upper and lower faces. The film is then applied to the rear vertical face of the load in such a way as to form a closed loop completely surrounding the load. The two ends of the loop are then combined in the vicinity of the rear vertical face of the load.

The dimensions and the nature of the loop may be varied within a considerable range, in accordance with the particular load to be packed.

For the operations of unwinding the film from the stock reel and forming the vertical curtain, use is made of a cylindrical transfer magazine. A certain length of film, cut from the stock reel, is wound into the said cylinder, situated in the vicinity of the said stock reel. The cylindrical magazine is movable. The said magazine, on which is wound the cut length of film, is then moved vertically downwards, as far as a point in the vicinity of the means for the storage of the film. The length of film wound onto the magazine is unwound towards the said store, the end of the length of film being kept attached to the cylinder. Finally, the cylindrical magazine is moved vertically upwards, thus forming the vertical curtain, kept stretched between the cylinder and the storage means.

FIG. 9 shows an upper magazine 100 containing a number of reels 102 of which the axes are horizontal. These reels are held and controlled by a system 103. The packing film 104 stored on a reel 102 penetrates, via the lower wall of the magazine 100, an assembly 105 serving for the selection, delivery, cutting and withdrawal of the films used. The assembly 105 is automated from a device which is not shown and which analyses the dimensions and nature of the load 106 to be packed. A small portion or leader 700 of the film selected is drawn down below the assembly 105. A cylindrical magazine 108 comprises a system 111 to enable the cylinder to grip this leader 107. Furthermore, the device comprises a lower reserve 109 situated below the transport rollers 110 of the load 106 to be packed.

FIG. 17 shows the equipment of the cylindrical magazine 108, which comprises, at each of its ends, a pinion 112 and sliding jaws 113, resting against guides, not shown in the drawing. This device is kept horizontal by engagement on the group of chains 114-115 and 116-117. Each of the groups of chains is actuated by a motor 118 or 119, via return pinions. The said return pinions, i.e. the upper ones 120 and the lower ones 121, are mechanically and kinetically integral. It can thus be seen that during the rotation of these pinions the cylinder 108 remains horizontal. The circuits of chains 114-115 on the one hand and 116-117 on the other are actuated independently of one another. Consequently, the combination of the movements of these two circuits suffices to impart to the cylinder 108 eight different movements or rotations, in addition to stoppage: ascent or descent (with or without rotation), rotation alone, the said rotation being possible either to the left or to the right.

The method of operation is as follows:

The automated assembly 105 receives signals produced by the analysis of the load 106 when the latter moves forward. In accordance with these signals, the assembly 105 selects a real 102 on which is wound a film of the nature, width and thickness suitable for the load 106. The selector 105 then extracts a leader 107, i.e. the end of the packing film 104 selected. At the same time, the kinetic circuits of the cylindrical magazine 108 are acruated to cause the said cylinder to ascend as far as a point just underneath the selector 105. The fact is that the jaws 113 preserve the engagement between the chains such as 115 and the pinions 112 of the ends of the cylinder 108. When the cylindrical magazine occupies its upper position, the system 111 grips the leader 107 of the film and closes (FIG. 10). By means of the devices shown in FIG. 9 the cylinder is caused to rotate (as shown by the arrow 123) and stores up an length of film 104, this length being determined on the basis of the analysis of the load 106 to be packed (FIG. 11). When the wound length is sufficient, the cilm is cut at the level of the assembly 105, in such a way as to leave a leader 107 for the following load. The movement of the chains is reversed and the cylindrical magazine 108 returns to the low position along the vertical axis 122 (FIG. 12).

When it occupies this low position, i.e. just above the path along which the load 106 moves, and ahead of this load, the cylindrical magazine 108 is set in rotation in accordance with the arrow 124. The end 125 of the film moves into position opposite an upper aperture 126 provided in the lower store 109. A certain portion of the transferred length 108 of the film 104 unwinds into this lower store (FIG. 13). At the end of this operation the cylindrical magazine re-ascends to its upper position, this return movement being accompanied by a rotation of the cylinder about its axis, so that a length of film re-winds about the cylinder 108. The various movements effected by the cylinder 108 are independent. They are combined in such a way as to form, ahead of the front face of the load 106 to be packed, a stretched vertical curtain 127 consisting of the film 104 (FIG. 14).

The operation of packing this load 106 is shown in FIGS. 15 and 16. The load 106 advances (as shown by the arrow 128) and takes with it, while subjecting it to deformation, the stretched portion 127 of the film. During this movement the length 129 of film 104 in the store 109 is extracted from this latter, the film interposing itself between the track 110 and the load 106. At the same time the upper part 130 of this film unwinds from the cylindrical magazine 108. As soon as the load has moved by a sufficient distance the automatic system sets up the descent of the cylinder 108 (arrow 131, FIG. 16) to cause the packing film to come to rest first against the upper face and then against the rear face of the load 106 when the cylindrical magazine 108 has reached its lower position, and behind the load 106 the gripping system 111 opens and frees the end of the film, of which the two edges are then opposite each other. They can perhaps be interconnected by a known process in such a way as to form a closed or hermetic packing.

A fresh load 106 then moves forward on the conveyor 110. The packing cycle recommences, in accordance with the same operations, as shown in FIG. 9.

In a first variant of the process using the horizontal stock reel, the operations of unwinding the film from the stock reel and forming the vertical curtain are performed in the following manner: The desired length of film is wound, without cutting it, onto the cylindrical magazine, which at this moment is situated in the vicinity of the stock reel. The said stock reel is then secured in position and the cylindrical magazine moved vertically downwards, in such a way as to form, ahead of the load, the curtain of film, which this time is kept stretched between the stock reel and the cylindrical magazine.

FIGS. 18-23 show the device corresponding to this variant. The cylindrical magazine 132 replaces the lower store 109. For this purpose, the vertical travel of the cylindrical magazine 132 enables it to be moved into position below the track 110. The cylinder 132 is caused to perform the same movements as those described previously. The devide comprises an upper jaw 133 and a lower jaw 134, consisting of horizontal bars and shafts parallel to those of the stocks reels and of the cylindrical magazine (FIG. 18).

The operation of the system is based on the utilization of the movements of the cylindrical magazine 132, effecting the transfer of the film (rotation as indicated by the arrows 135a and 135b, and vertical movement as indicated by the arrow 136 or 137). A stretched curtain 127, stretched vertically in front of the load 6, is thus formed. The advance of this load on the conveyor 110 results in the unwinding of the cylindrical magazine 132 containing the reserve of film, into the lower position, and also the partial unwinding of the stock reel 102, into the upper position (FIG. 22). The jaw 133 is movable vertically (arrow 138). The jaws cause the packing film to come to rest against the upper part and the rear part of the load 106, while the gripping device 111 of the transfer cylinder 132 frees the end of the film. At this moment the said device 111 and the jaw 133 move into position opposite each other. The jaw 133 in the lower position (FIG. 23) cuts the film and introduces it into the gripping device 111 for the cylindrical magazine 132.

FIGS. 24 and 25 show a second variant of the packing device with horizontal stock reel, in which variant the vertical movement of a film transfer cylinder is eliminated. The operation of feeding the film to this transfer cylinder 132a and gripping it by means of the device 111 are ensured by the jaw 133, to which a vertical movement is imparted. The transfer cylinder 132a, constantly situated below the track 110, is simply caused to perform direct and indirect rotations. The gripping device 111 makes it possible, after the passage of each load 106, to form the curtain of film 127 stretched vertically ahead of the subsequent load.

In another variant of the process to which the invention relates, the film is constantly connected to the stock reel as in the examples shown in FIGS. 18-23 and is hooked to an intermediate cylinder which keeps the film stretched vertically. Subsequently, the rotation of the intermediate cylinder about its axis is practically zero when the load deforms the curtain, but on the other hand the axis of this cylinder is caused to perform a traversing movement in order to approach the stock reel.

As will be seen in due course, the traversing movement of the intermediate cylinder is either vertical (FIGS. 26 and 27) or horizontal (FIGS. 28-30).

The devices corresponding to these variants are shown in FIGS. 26-30. The intermediate cylinder is non-rotatable, It is fitted with a gripping device 111 for the end of the film.

In the case of the third variant of the device, as shown in FIGS. 26 and 27, a vertically movable upper jaw 133 and a counter-jaw 135 are provided, the latter occupying a fixed position. The cylinder 140 is merely caused to perform a vertical traversing movement along a track situated underneath the conveyor 110. The curtain 127 is produced by combining the ascent of the intermediate cylinder 140, the opening of its gripping device 111 and the descent of the upper jaw 133, introducing the end of the film into the said gripping device.

In the case of the fourth variant of the device, as shown in FIGS. 28-30, the intermediate cylinder 140 is moved not vertically but in a horizontal plane underneath the conveyer 110.

The vertical movement (FIGS. 26 and 27) or horizontal movement (FIGS. 28-30) of the intermediate cylinder 140 is necessary in both cases in order to deliver the length of film to be employed. The fact is that the cylinder 140 no longer functions as a magazine, as in the preceding cases, but keeps the film stretched vertically, ahead of the load.

In a fifth and last variant of the device, shown in FIGS. 31-33, the transfer cylinder is replaced by the driving devices, e.g. two presser rollers 141 and 142, with horizontal axes. The film 104 unwound from the stock reel 102 is introduced between the two rollers 141 and 142.

Known mechanisms impart of each of the rollers a rotatory movement (the two rollers differing in the direction of rotation) and a traversing movement in a vertical plane. These movements are independent.

Furthermore, the device is equipped with an upper jaw 143, movable in a vertical plane, and a lower jaw 144. The device also comprises a lower store underneath the conveyor 110. In the course of its operation the successive phases are as follows:

The two rollers 141 and 142 ascend and grip the leader 107 of the film 104 by rotation.

The rollers 141 and 142 re-descent without rotating, taking the film with them.

The rollers 141 and 142, reaching the lower position, are caused to perform a rotatory movement which enables the film to be delivered into the lower store (FIG. 32), while the curtain 127 is formed ahead of the load 106 to be packed.

The load 106 is caused to move forward towards the curtain 127 and is packed as a result of the vertical movement of the upper jaw 133.

It will be noted that no description has been given of the known devices used in this apparatus, particularly the automation and data-storage systems.

A device according to the invention can be controlled either automatically or manually. In all cases it offers the essential advantage of increasing the packing output, eliminating falls and rejects in the packing material and enabling loads of very different nature and size to be packed on one and the same conveyor and from one and the same device. Similarly, it enables films of different kinds to be used (and rapidly replaced).

Needless to say, as in the first variant, with vertical reel, the intermediate cylindrical magazine or transfer cylinder can be replaced by any other equivalent device of prismatic or similar shape, or even, if this cylinder is largely or completely immobile, solely by the gripping device 111. This latter takes, for example, the form of two longitudinal jaws borne by the transfer cylinder, but any other gripping device can be considered.

Claims

We claim:

1. A method of packing a load in a film of material, comprising;

moving a length of film approximately corresponding to a periphery of the load to be packed from a supply area, and around an axis thereof into a cylindrical transfer magazine with a shaft, parallel to said axis; thereafter

moving said magazine relative to the load and around the load starting form a point in the vicinity of the supply area to form a loop of film around the load, the film moved onto the cylindrical magazine being progressively unwound therefrom in the course of such moving of the magazine to apply the film of the load; and

then joining ends of the film edge to edge.

2. A method in accordance with claim 1, including, securing the supply area against moving of additional film material therefrom during the moving of the cylindrical magazine around the load.

3. A method in accordance with claim 1, including braking the cylindrical magazine against rotation thereof during said moving thereof about the load, to stretch the film unwound therefrom.

4. A method in accordance with claim 1, including stretching the film during the moving thereof onto the cylindrical magazine.

5. Machine for packing a load in one single film emanating from a stock reel, comprising;

one single cylinder of which the axis is parallel to that of a stock reel;

means for winding film emanating from the stock reel on said cylinder to make it a cylindrical magazine; and

means for moving the cylinder along a given kinetic circuit, so that the axis of the cylinder will be kept constantly parallel to the stock reel and that the film will progressively form a loop completely surrounding the load.

6. Packing machine in accordance with claim 5, including a vertical shaft for the single cylinder; first driving means for moving the shaft of the cylindrical magazine along said circuit; and second driving means for causing the cylindrical magazine to pivot about its shaft independently of the position of this latter on the circuit.

7. Packing machine in accordance with claim 6, in which said circuit comprises a guide track which consists of a slide bar forming a loop having an internal opening larger than the load to be packed, in a horizontal plane.

8. Packing machine in accordance with claim 6 in which the first and second driving means comprise two horizontal and concentric circular rims, including an internal rim and an external rim, having teeth facing towards the external rim and teeth facing towards the internal rim, respectively; a pinion borne by the shaft of the cylindrical magazine and drivable by the internal circular rim and the external circular rim for enabling either of the two circular toothed rims to pivot, independently of the other, so as to enable moving the shaft of the cylindrical magazine along the guide track and turning said cylindrical magazine about the pivot shaft.

9. Packing machine in accordance with claim 7, including jack means acting on the shaft of the cylindrical magazine to move it along at least one portion of the track, said cylinder being mounted, with moderate friction, about its shaft so that movement of said shaft automatically causes the cylindrical magazine to pivot about its shaft, owing to tension of the film held on the stock reel.

10. Packing machine in accordance with claim 7 wherein the guide track consists of at least one fixed horizontal slide bar and a perpendicular horizontal traverse, supporting the cylindrical magazine.

11. Packing machine in accordance with claim 5, comprising a number of stock reels for films of different characteristics; an upper magazine for said reels, having a lower part with a system for selection of delivery and cutting of a film; means for winding a length of the selected film onto the cylindrical magazine; means for imparting to said cylinder a rotatory movement and a vertical traversing movement between the upper magazine and one of the stock reels for film, whereby moving the cylindrical magazine along said circuit enables said magazine to extract a selected film and to store a known length thereof on a stock reel and also enables the loop to be formed as a result of horizontal movement of the load.

12. Packing machine in accordance with claim 11, in which the means for imparting movement to the cylindrical magazine comprise a guide track for the shaft of the cylindrical magazine, two belts lognitudinally movable along the guide track, two pinions on the respective two sides of the latter, and two motor units driving the belts independently of each other, in such a manner as to transmit the movements to the cylindrical magazine, of which the axis remains constantly horizontal.

13. Packing machine in accordance with claim 11, including a film selection system and an automatic device for reading the dimensions of the load to be packed to control the film selection system.

14. Packing machine in accordance with claim 5, including means for pivoting the cylindrical magazine and the stock reel, in such manner that their peripheral speeds differ.

15. Packing machine in accordance with claim 5, including means for braking movement of the cylindrical magazine about its axis.