IE44453B1 - Improvements in and relating to container forming and filling machines - Google Patents

Description

This invention relates to container forming and filling machines, - and more especially to a machine for the manufacture on an industrial scale of packaging containers from a thermoplastic material that shrinks under the influence of heat.

A cup-shaped container is known made from a laminated material which comprises a carrier layer of foamed plastics. The preferred material from which this known container is made comprises a carrier layer of foamed plastics with thinner layers of homogeneous plastics material on each face. The cells constituting the foamed plastics layer are of lenticular or elongated shape which is ensured by stretching the material after extrusion. Since the cells are normally spherical and endeavour to assume once more this normal shape they attempt, when the finished material is softened by heating, to revert as far as possible, to the spherical shape, in consequence of which the material shrinks. Thus the thermoforming of a sheet of the material, e.g. round a profiled mandrel can be effected without the cellular structure being changed or excessive variations of thickness occurring. As an example of a suit20 able material may be mentioned a laminate comprising a carrier layer of polystyrene foam plastics and layers of homogeneous polystyrene applied to each side thereof. The foamed plastics layer may have a thickness of 0.6 mm and the homogeneous polystyrene layers have a thickness of 0.1 mm.

A container made from the abovementioned material has a number of advantages compared with cup-shaped containers made by heating the vacuum-forming a plastics web. Since the material at the surface of the container is not stretched or bent during the manufacture it is possible to decorate the material in web form, which previously was not possible, since the vacuum-forming of the material distorts the decorating pattern or an applied legend. In addition the foamed plastics layer included in the material provides insulating properties which make it especially suitable for hot beverages or iced liquids.

The object of the invention is to provide a machine for production of containers such as indicated above on a commercial scale, and with this end in view the invention consists in a container forming and filling machine comprising a mandrel shaped to define . the internal container shape, means for shrinkforming a sleeve of heat-shrinkable material to container form on said mandrel, apparatus for filling a container with desired contents, and means for transferring a container formed on said mandrel to a filling station.

One embodiment of a container-forming machine incorporating the invention, given by way of example, will now be described in detail with reference to the accompanying, partly-schematic, drawings, in which the same details are identified by the same references in all figures.

Fig. 1 shows in the form of a flow diagram stages during the manufacture of a container in accordance with the invention; 4-153 - 4 Fig. 2 shows schematically and in perspective a machine in accordance with the invention; Fig. 3 is a side view of the machine in accordance with the invention, shown partly in section; Figs. 4 to 8 show mechanism incorporated in the machine for the feed of web packaging material; and more particularly Fig. 4 shows in perspective means for imparting a reciprocating movement to a feed unit. Fig. 5 shows in perspective means for actuating web-holding arms in the feed unit; Fig. 6 a detail of transmission included in the mechanism shown in Fig. 5; Fig. 7 the feed unit in perspective; and Fig. 8 the feed unit in section with the web-holding arms in closed (fully drawn lines) and open (dash-dotted lines) positions.

Fig. 9 shows in perspective a unit included in the machine for cutting the web into individual blanks; Fig. 10 is a side view of the cutting device forming part of the unit shown in Fig. 9, Figs. 11—15 show from above and partly in section successive stages of the cutting device during cutting of the web; Fig. 16 is a side view partly in section of a mandrel unit forming part of the machine, a driver element co-operating with the mandrel, a holding finger co-operating with the mandrel and actuating means for these elements; Fig. 17 is a section through the mandrel shown in Fig. to illustrate ducts provided in the mandrel; Fig. 18 shows in perspective means for the rotation of the mandrel shown in Figs.16 and 17 together with means for actuating the driver element shown in Fig. 16; - 5 Fig. 19 shows in perspective means for operating the holding finger shown in Fig. 16; Fig. 20 shows in perspective a hot-air nozzle for heating the strip material and means for operating the hotair nozzle; Fig. 21 shows the hot-air nozzle shown in Fig. 20 from above and in advanced, active, position; Fig. 22 shows the same hot-air nozzle in retracted, inactive, position.

Fig. 23 shows in perspective an element co-operating with the mandrel for forming the strip material, and means for operating the element; Fig. 24 shows from above the forming element shown in Fig. 23; Figs. 25—31 show step-by-step the forming element, the mandrel, the holding finger and the hot-air nozzle in their co-operating positions during the formation of a sleeve blank; Fig. 32 shows in perspective means for feeding a strip of connected base blanks, a cutting element for dividing the strip into individual base blanks, and means for the transfer of the individual base blanks to the end of the mandrel; Fig. 33 shows means for actuating the elements in Fig. 32; Fig. 34 is a detail view, from the side, of the basetransfer means shown in Fig. 32; Fig. 35 shows in perspective a unit located beneath the mandrel for heating and bonding together a sleeve blank and a base blank, and means for operating the unit; ' 4 4453 - S Figs. 36—‘39 are side views of the mechanism shown ;in Fig. 35, and in particular Fig. 36 shows the unit in a ready to function position; Fig. 37 the unit in sleeve-shrinking position,· Fig. 38 the unit in a base pressing position? and Fig. 39 the unit in a position to receive a container for transfer: and Fig. 40 shows container-transfer mechanism.

Fig. 1 shows step-by-step the transformation from a strip of heat-shrinkable packaging material, of a cup-shaped container as carried out in a machine in accordance with the invention. A web of material is fed to the machine and divided into separate sheets 1 of a prearranged length. The material is provided with an inserted thread (not shown) which extends close to and parallel with the top edge of the material to serve as a tear-thread for opening the finished container. To facilitate the gripping of the end of this thread the web material is cut so that a projecting lug 2 appears at one corner of each sheet 1 and a corresponding cutout or recess 3 at the corresponding corner at its other end. The cut sheet 1 is heated and formed into a tubular shell blank 4 by winding it round a mandrel (not shown) and its two short opposite end edge zones are joined together along an overlap seam, or longitudinal joint 5. The lug at the end of the sheet 1 is - not attached to the surface of the blank 4 but stands up slightly from the sleeve 4, which is then dis25 placed so that its bottom end projects beyond the end of the mandrel. Into the projecting end a base blank 6 is introduced, to rest against the end of the mandrel, whereafter the sleeve and the base blank are heated. As a result of the heating the sleeve shrinks until it fits accurately to the shape of the mandrel, which has been selected in accordance with the desired shape of the finished container. In the example illustrated the container has a substantially cylindrical t - 7 upper part 7 .and adjoining it a slightly frusto-conical lower part 8. The bottom edge zone of the sleeve 4 which projects beyond the end of the mandrel, on shrinking under heat, folds-in against the end of the mandrel and against the base blank 6 resting against the mandrel. The folded-in edge zone of the blank 4 covers an edge zone of corresponding width on the base blank 6, and while the two edge zones are still heated an assembling and base forming device is pressed against the base of the container, as a result of which the edge zones are pressed together as an annular, impervious, overlap seal. At the same time the outside of the base of the container is given a suitable shape. The finished container, in its final form, is transferred to other apparatus for filling and subsequent covering with a lid.

The filling machine which is built together, and forms one unit, with the container-forming machine in accordance with the invention. In the filling machine lids are punched out of a web, and thermoformed in conjunction with the punching process to acquire a recessed central area and a surrounding flange 11. After the container has been loaded with the desired contents, the upper edge of the container is heated, and the similarly heated lid 9 is pressed down into the container, so that the flange 11 bears against and is loaded to the container lip by an impervious seal. The finished and closed container is moved away to be packed, for example, into bulk carriers or crates.

A preferred embodiment of the machine in accordance with the invention will now be described, first in a general machine description, with reference to Figs. 2 and 3, the drive of the complete machine and the path of the packaging material 444 5 3 - 8 I through the machine in the course of being formed into individual, filled and sealed containers. ί Following an account of the design and functional characteristics of the machine in the general description, the units included in the na chine for the execution of the different container-forming phases will be described in more detail and the different units will be described in the sequence in which they come into operation during the manufacture of an individual container, and with specific reference to the different detailed drawings.

General Machine Description.

The container-forming machine 12 is combined with a substantially conventional filling apparatus 13 to form a container forming and filling machine in 'acc'orda'nce with thd invention. The complete machine as -shown in Fig. 2, incorporates only one container-forming machine 12 feeding the filling apparatus. However, it is advantageous in practice to couple a filling apparatus with a larger number of container-forming machines, e.g. four or eight, depending on the capacity of the filling apparatus A combined machine with a greater number of container-forming units is of design ! similar to the machine shown in Fig. 2 except that it extends towards the left with the addition of further container-forming machines 12, which are disposed parallel with the container-forming machine shown in slightly spaced positions, so that they can be served by the same driving and conveyor elements, as described in greater detail below.

The filling apparatus 13 included in the complete machine is of substantially conventional type and comprises a box-shaped frame 14 around which runs an endless apron feeder 15 with apertures 16 for the containers. The upper run of the conveyor 15 proceeds away from the containerforming machine 12, that is to say from left to right as seen in the drawing. The conveyor 15 runs over four guide rollers 17, one cf which drives it.

Inside the box-shaped frame 14 is a main motor 18, which by a chain drives a main shaft 19. Transmission of the drive follows in three different directions, namely firstly by an indexing gear box 20, located at the one end of the main shaft 19, bevelled gears 21 connected therewith and a chain drive 22 to the drive shaft of the conveyor 15, secondly by a chain drive 23 located at the other end of the main shaft 19, and bevelled gearing 24 to a transport chain 25, which transfers cups from the forming apparatus 12 to the filling apparatus 13, and thirdly by a further chain drive 26, located at the last-mentioned end of the main shaft 19, which transmits the drive to a layshaft 27 mounted alongside the frame 14 and extending parallel with the main shaft to the containerforming machine 12. In the forming machine 12 the force is transmitted from the layshaft 27 by a chain 28 to a lower camshaft 29, which in turn transmits the driving force by two . toothed belts 30 and 31 respectively to an upper camshaft 32, and a camshaft 34 of a programming mechanism 33. The cam discs of the lower and upper camshafts 29 and 32 respectively transmit the driving force by lever arms to the different elements included in the container-forming machine, which will be described in greater detail below.

The layshaft 27 also drives, by a belt 35, a magazine roll 36 for the unused portion of a web of material from which the lids 9 of the containers have been punched (this roll 36 being supported on the top of the filling apparatus 13). - 10 The (or each) container-forming machine 12 may be regarded as consisting of three box-shaped frame sections within which the different elements are grouped, namely a first or upper section 37,. a second or lower section 38, located underneath the first section and a roll stand 39 beside or behind the first section. The roll stand 39 supports a freely rotating roll 40 of a web 41 which is drawn off over a guide pulley 42 in the upper machine section 37, to be divided into separate sheets 1 to be formed into tubular sleeves or blanks 4 by winding round a mandrel 43 supported in the upper or first machine section 37.

In the roll stand 39 a second roll 44 of web material is also supported so and freely rotatable. From the roll 44 is drawn a continuous Web 45 of blanks 6 for the container bases. This web passes into the lower machine section 38 and is divided into separate base blanks, each of which is bonded to a formed sleeve 4, so as to produce a cup-shaped container, open at the top. The container thus formed is then passed to the transport belt. 35, which conveys it to an aperture 16 in the conveyor 15 of the filling apparatus 13. The conveyor 15 then moves the cup to a position underneath a filling unit 46 mounted on the upper part of the filling apparatus 13 where it is loaded with the desired quantity of contents, whereafter the conveyor 15 is indexed and moves the cup to a position underneath a lid unit 47, (also mounted on the upper part of the filling apparatus 13.) which from a web of lid material drawn from roll 48 punches out individual lids 9, thermoforms them to provide the recessed central area 10 and the flange 11, heats the flange 11 as well as the upper edge of the cups in the conveyor, and seals the lid so that the filled container is closed. By further indexing of the conveyor 15, the finished and closed container is moved to a position in line with a chute 49 into which the container is 4453 passed by devices (not shown) for further transport, and if desired packaging into bulk carriers or the like.

The details of construction of, and the connection between, the different units of the container-forming machine 12 can be recognized more clearly from Fig. 3, which is a side view of an upper and lower machine section 37, 38 of a forming machine 12, as seen from the left of Fig. 2.

Function Description The web 41 of heat-shrinkable foamed plastics material is drawn from roll 40 (Fig. 2) passes into the first or upper machine section 37 from the left (Fig. 3) and is fed by a feed unit 50 towards the mandrel 43. The feed unit 50 performs a linear reciprocating movement parallel with the web 41 and feeds it intermittently. The feed unit 50, and the other units located in the first or upper machine section 37, are driven by a lever system, and belts or the like, from the cam discs of the upper camshaft 32. The various elements provided for this purpose and the method for transmitting and converting the drive to the individual units are dealt with in more detail below with reference to specific detailed drawings.

Following the feed unit 50 (seen in the direction of movement of the web 41) is a cutting device 51 which divides the web 41 into successive lengths or sheets each suitable for forming a sleeve or blank 4. Simultaneously with the cutting movement of the cutting device 51, the front end of the sheet 1, then close to the peripheral surface of the mandrel 43, is gripped against the mandrel surface by a holding finger 52 (Fig. 16), and after the completion of the cutting, the mandrel 43 commences to rotate. As soon as the mandrel commences to rotate, a hot-air nozzle 53 is moved to an active position, (Figs. 21, 22) and a hot-air stream is blown at an angle between the surface of the mandrel and the contiguous sheet. Thus the material is heated to such an extent that the formation of the sheet into tube-form is facilitated. When the mandrel 43 has almost completed one , turn, and when the trailing end of the sheet 1 is directly in front of the mouth of the hot-air nozzle 53, the rotation of the mandrel 43 stops, and the leading and trailing ends of the sheet 1, immediately opposite one another, are exposed to the hot-air for a longer time than the remainder of the sheet and are thus heated to the softening temperature. Then the heated and overlapping end edge zones of the sheet are pressed together, to form an overlap joint, by a pivotable sleeve-forming device 54, which during the greater part of the mandrel rotation, presses the sheet lightly against the surface of the mandrel, but which as a rotation is completed is pivoted to apply a vigorous pressure to the two overlapping sheet ends. After completion of the longitudinal seam the mandrel rotates a little further, so that it completes a full turn and once more attains its starting position.

After the sleeve-forming device 54 and the hot-air nozzle have returned to their rest positions, the formed sleeve 4 is detached and is moved, by a driver element 55 (Fig. 16), downwards axially of the mandrel 43 to such a position that the bottom end of the sleeve projects a little beyond the end of the mandrel. · The processing of the tubular sleeve 4 is now taken over by the processing units located in the lower machine section 38 v/hich are driven by levers and like elements from the cam discs of the lower camshaft 29. The drive of the different units and their details will be described below with reference to the specific detailed drawings. t By a base feed wheel 76 the container bases 6, in the form of a continuous web 45 in the roll stand 39, are fed into the lower machine section. The web 45 passes round the stepby-step rotating feed wheel 76 to an adjacent cutting element 56 (Fig. 32), which divides the continuous web 45 into separate base blanks 6. Directly adjoining the cutting element 56 is a base transfer device 57, which grips each separated base blank 6 and places it in contact with the underside of the mandrel 43, where the base blank 6 ia retained by vacuum, being surrounded by the projecting edge zone of the sleeve 4.

With the sleeve 4 and the base blank 6 in this position a tubular heating element or hot-air oven 58, located underneath the mandrel, is raised to an upper active position in which it surrounds the bottom end of the mandrel 43 and heats the sleeve and base blank 4, 6 thereon. As a result of the heating the sleeve 4 shrinks and conforms accurately to the shape of the mandrel 43. The projecting edge zone of the sleeve 4, as well as the base blank 6, being located in the lower, warmer, section of the oven, are heated to a greater extent than the remaining, upper portion of the sleeve 4, and in consequence the edge zone of the sleeve shrinks to adhere against the edge zone of the base blank 6, and, before the shrinking oven 58 is withdrawn, the material in the two abutting edge zones attains its softening and welding temperature.

To the left of the heating element or oven 58 and parallel therewith is an assembling device 59 (Fig. 3) which together with the shrinking oven 58 and a gripping element 60 on the top edge of the same (Fig. 36) is combined as a unit 79. When the shrinking oven is lowered to its rest position the unit 79 is moved one step towards the right (Fig. 3), 444 5 3 - 14 whereupon the assembling device 59 is raised to bear against the still-soft edge zones of the base blank and the sleeve so as to press them together to form an impervious overlap seam. The forming of the container is thus finished, and the assembling device 59 is lowered again to its rest position (shown in the drawing). Subsequently the unit 79 consisting of the assembling device 59, the shrinking oven 58 and the gripping element 60 comes to rest immediately beneath the mandrel 43. The driver element 55, and the help of an intermediary in the form of a new sleeve formed during the shrinking process, pushes the finished container downwards to the gripping element 60, and when, during the next operative cycle, the unit is moved once more towards the right, the container is transferred to the transport chain 25 and conveyed to the filling machine.

Machine Description in Detail: Web Feed Unit.

The web feed unit 50 and its driving means are illustra ted in Figs. 4—8. The feed device itself is shown in Figs. 7 and 8 and comprises two supporting plates 61, 62 which are in spaced parallel positions and substantially triangular in shape. The plates 61, 62 are each provided near their two upper corners with drilled holes 63 by which the feed unit is slidably suspended on two parallel guide rods 64, 65.

Between these rods extends an operating shaft 66, rotatably mounted in the plates 61, 62, but not axially movable therein On the part of the shaft 66 between the supporting plates are two spaced nipping arms 67, 68 fixed to the operating shaft 66. These arms extend obliquely downwards from the shaft 66 and are rockable between an active position (full lines) and an inactive position (dash-dotted lines). The t nipping arms 67, 68 co-operate with a counter-grip 69, which is supported for rotation on a shaft 70 extending between the lower corners of the supporting plates 61, 62. The countergrip 69 is rockable between two positions, namely an active position (full lines in Fig. 8) and an inactive position (dash-dotted lines), and is operated, as are the arms 67, 68 to move between the active and the inactive positions by turning of the operating shaft 66. The counter-grip 69 is not connected directly to the operating shaft 66, however, but is actuated by a toggle joint assembly, which comprises a lever arm 71 connected to rotate with the operating shaft 66, and extending towards the counter-grip 69? a sleeve 72 which is axially movable along the lever arm 71 and which, by a helical spring 73 surrounding the lever arm 71, is urged towards the counter-grip 69. The sleeve 72 has in its lower edge two U-shaped slots 74 located opposite one another, which open downwardly and which accommodate two pins 75 provided at the upper end of the counter-grip 69. The sleeve 72, which is axially slidable along the lever 71, is urged by the spring 73 permanently to bear against the pins 75.

When the nipping arms 67, 68 and the counter-grip 69 ϊ are to be pivoted e.g. from the active to the inactive positions, the operating shaft 66 is turned in anti-clockwise direction as seen in Fig. 8 so that the arms 67, 68 and the lever 71 are pivoted in anti-clockwise direction. The lever arm 71 with the sleeve 72 acts as a toggle in association with the upper end of the counter-grip 69, so that the countergrip rocks clockwise to the inactive position.

The operating shaft 66 not only rocks the parts of the feed unit which hold or release the web 41, as described, but also effects the reciprocating movement of the feed unit 50, 444 53 which, as mentioned earlier, is supported so that it can be displaced on the two parallel guides 64 and 65. The one end of the operating shaft 66, as mentioned earlier, is mounted so that it can be turned but not axially displaced in the feed unit 50. Thus, an axial movement of the shaft 66 displaces the feed unit 50 along the guides 64, 65. The other end of the shaft 66 is supported so that It can be turned but not axially displaced in a bearing yoke 77, (Figs. 5 and 6) which like the feed unit 50 is supported by and displaceable along the guides 64, 65. The bearing yoke 77 is provided on its upper face with an attachment 78, by which it is connected to a toothed belt 80 (Fig. 4). Over a prearranged distance this belt runs parallel with the guides 64, 65, whereafter passing round guide pulleys 81 it is connected at one end to a lever arm 82 which rests against and is acted upon by a feed cam .83 supported by the upper camshaft 32. At its other end the toothed belt 80 is held taut by a return spring 84, which not <5nly keeps the toothed belt continuously stretched, but also acts upon the lever arm 82 to hold it continuously against the periphery of the feed cam 83 during the rotation of the camshaft and thus to impart to the toothed belt 80 and a reciprocating movement accurately controlled by the cam 83.

To adjust the length of the working and return stroke of the feed unit 50, the length of the lever arm B2 between its pivot axis and the roller 85 at its lower end (which acts upon the toothed belt 80) can be adjusted by an adjusting device 86, One of the guide pulleys 81 over which the toothed belt 80 passes is provided with an eccentric bearing 87 which can be turned by a pne.umatic cylinder 88 so that the path of the toothed belt 80 is lengthened or shortened. This makes it t possible to adjust the position of the decoration provided on the web 41, as follows: The web 41 being fed into the machine is provided with equispaced marks detectable by photo cell means. These are scanned continuously by photo-cell means located close to the feed path of the web (not shown in the drawings), and the pulses transmitted by the photocell when detecting the marks are compared continuously with pulses from the programming mechanism 33 installed in the machine, and set to transmit pulses at a prearranged point in the working cycle. Thus, if a pulse from the photo-cell coincides with a pulse from the programming mechanism, the feed is correct and a pneumatic stepping cylinder which is provided does not act upon the eccentric bearing 87 of the pulley 81. To ensure that the length of the feed stroke is kept at the correct value a pre-arranged overfeed always takes place, however. This is set by an extension of the lever arm 82 by the adjusting device 86. A resulting time difference arises between the pulse from the photo-cell and the pulse from the programming mechanism 33, which time difference is scanned and controls a pneumatic valve which acts upon tlie pneumatic cylinder 88 (Fig. 4) so that the same, during the working stroke of the lever arm 82, turns the eccentric bearing 87 of the guide pulley 81 and thereby shortens the path of the toothed belt 80. Thus the working stroke of the feed unit is somewhat shortened. During the return stroke the eccentric bearing 87 is restored to a neutral position, and at the working stroke the difference between the pulses is scanned once more and the said correction of the length of stroke again effected.

The rotation of the operating shaft 66 which actuates the nipping arms 67, 68 and the counter-grip 69 to move 4453 between the active and inactive positions is effected by a lever arm 89 (Fig- 6) fixed to the operating shaft 56, each time the feed unit 50 reaches an end position of its reciprocating movements. The lever arm 89 is mounted at the end of the operating shaft 66 which is supported in the bearing yoke 77, and the lower end of the lever arm extends below the bearing yoke, where it carries a pin 90 which is parallel with the operating shaft 66 and projects from both sides of the lever arm 89. The pin 90 is displaced by one or other of two rocker arms 91, mounted adjacent to the two end positions reached by the bearing yoke 77. The rocker arms are supported on an intermediate shaft 92 located beneath the shaft 66. The intermediate shaft 92 is rotatably supported in the machine frame for reciprocation between two angular positions. The rocking is effected by a cam 93 (Fig. 5) of the upper camshaft 32, (hereinafter referred to as the holding cam) which controls a lever arm 95, kept in contact with the cam 93 by a spring 94, and a lever arm and link unit 96, connecting the lever arm 95 to the intermediate shaft 92. This mechanism transmits the movement determined by the holding cam 93 to the operating shaft 66, to bring the nipping arms 67, 68 and the counter-grip 69 to the active web-gripping position when the feed unit 50 is in its rearmost withdrawn position, and to the inactive, web-releasing position when the feed unit is in its forward advanced, position. In this way the intermittent feed of the web to the container-forming units of the machine is achieved. Web-Cutting Device.

The web-cutting device 51 located downstream of the feed 50 as illustrated in Figs. 9 and 10, and the operation of the cutting device will be described with reference to Figs. 11-15.

The cutting device 51 comprises two spaced guides 97 at right angles to the web 41, provided on their facing surfaces with V-shaped grooves which slidably support the rear end of a knifeholder 98. The knifeholder is provided at its inner face with a knife 99 and a pressure plate 100 immediately adjacent to the Icnife. The pressure plate is displaceable towards and away from the web 41 and is urged towards the web by two compression springs 101. The knife 99 and the pressure plate 100 co-operate with a fixed counterblock 102 on the opposite side Of the web 41.

The knifeholder 98 during operation of the machine performs a working and return stroke and is actuated by a cam 103 on the upper camshaft 32. The cam 103 will be referred to hereinafter as the cutting cam. An L-shaped lever 105, of which one limb is held against the cutting cam by a spring 104, the other limb driving a linkage and lever unit 106 mounted on a vertical shaft 107, which rotates in the machine frame and is located close to the knifeholder 98. Rotation of the shaft 107 is transmitted by a forked driver 108 mounted on the shaft 107 and coupling bushes 109 carried by the fork arms, to the knifeholder 98 which is thereby reciprocated under the determined accurate control of the cutting cam 103.

Figs. 11“15 show schematically successive stages of the cutting process. In Fig. 11 the knifeholder 98 is in an inactive position in which the knife 99 and the pressure plate 100 are retracted and spaced from the web 41, which moves in the direction of the arrow 110 and at some distance from the counterblock 102 behind it. In Fig. 12 the web 41 has been advanced by the feed unit 50 which has come to rest and the cutting device 51 has been activated. The knife4 4 4 5 3 - 20 holder 98, upon the rocking of the shaft 107, has been moved towards the web 41 which is pressed by the spring-loaded plate 100 against the counterblock 102. In Fig. 13 the knifeholder 98 has been further moved in the same direction, and the knife 99 has severed the web and separated a sheet 1 which at its front leading edge is gripped to the mandrel 43, and upon rotation of the mandrel is drawn. In the direction of the arrow 111. In Fig. 14 the initial withdrawal of the knifeholder 98 is shown„ and the knife 99 has left fche material while the pressure plate 100 continues to retain the material in order to prevent it from sliding back. The sheet 1 has been drawn forward by the mandrel 43 in the direction of the arrow 111. In Fig. 15 the knifeholder 98 has been retracted until the pressure plate 100 has started to leave the web which can be advanced further, by another sheet length, by the feed unit 50.

Mandrel Unit.

The mandrel 43 (Figs. 16 and 17) is mounted by its upper end on a mandrel shaft 112, which extends upwards and is rotatably supported in the upper part 37 of the machine.

At the lower end of the mandrel shaft 112 is a belt pulley 113 rotatable together with the mandrel shaft and the mandrel, by which pulley the mandrel 43 can be rotated intermittently. Immediately underneath the pulley 113 is a brake disc 114, which is also fixed in relation to the mandrel and the mandrel shaft. Against the peripheral surface of the disc rests a brake shoe 115, mounted on a brake arm 116 and urged to bear against the brake disc 114 by a brake spring 117.

Referring to Fig. 17, the mandrel comprises a main body 163 which is substantially cylindrical with a frustoconical nose 164 at the bottom. Two ducts 165 and 166 extend ( - 21 vertically through the main body 163. At the bottom an insert 167 is screwed into the nose 164, and the duct 166 communicates with an annular groove 168 in the insert. The groove 168 connects the duct 166 to a number of peripheral holes 169 in the lower conical nose 164 of the main body 163. The duct 165 communicates with an axial extension through the nose insert 167 opening at the bottom end of the mandrel.

The main body 163 is firmly attached at its upper end to the mandrel shaft 112 and the two ducts 165 and 166 extend concentrically through the shaft 112 to the upper end thereof, and through a rotatable coupling 170 incorporating an inlet plug for each (only one of which is visible in Fig. 16).

The two air ducts 165 and 166 can be connected optionally to a source of vacuum or of pressure respectively, which is done by known means which are not described in detail. The duct 165 open at the free lower end of the mandrel is connected to a source of vacuum when a base blank 6 is presented to the end of the mandrel, so that the base blank 6 is retained during the further course of operation. The holes 169 of the air duct 166 ending at the conical nose region 164 of the mandrel 43 are connected to the source of vacuum in connection with the shrinkage of a sleeve 4 on the mandrel end, the vacuum contributing to make the lower part of the sleeve conform accurately with the conical region 164. When the ..ase blank 6 has been joined to the sleeve 4 and the container is to be detached from the mandrel 43 by a driving element 55, the two air ducts 165 and 166 are connected to the source of pressure, which prevents formation of a vacuum liable to obstruct detachment of the container from the mandrel.

The means for driving the mandrel 43 are illustrated in 44453Fig. 18 and comprise the belt pulley 113 fitted on the mandrel shaft 112, which, by an endless toothed belt 118 is connected to a freewheel arrangement 119. The freewheel arrangement 119 is turned by means of a lever arm (not shown), is connected by a link 120 to orii arm of a bell crank lever 121. The other arm of the bell crank lever 121 carries a freely rotatable roller 122, which is held by a helical spring connected to the lever 121 against a cam 123 (hereinafter called rolling cam) on the upper camshaft 32.

On rotation of the upper camshaft 32 the contour of the rolling cam 123 imparts a reciprocating movement to the bell crank lever 121, which through the link 120 and the lever arm (not shown) is transmitted to the freewheel arrangement 119. The rolling cam is designed so that for each turn of the camshaft 32 the freewheel arrangement 119 is turned substantially one quarter of a turn in the direction of the arrow 124. When the freewheel arrangement 119 is rotated by a quarter turn, (and in view of the selected transmission ratio between the two belt pulleys of the belt 118) the mandrel 43 is rotated substantially a full turn, (i.e. the said transmission ratio is 1:4).

The freewheel arrangement 119 would allow the mandrel, owing to its inertia, to continue rotating after the turning drive stopped, and to prevent this the brake shoe 115 is pressed by the brake spring 117 against the brake disc 114 on the mandrel shaft 112 during the rotation of the mandrel.

Immediately beneath the brake disc 114 mounted on the mandrel shaft 112 is an indexing sleeve 125 firmly mounted on the shaft (Fig. 16). This sleeve in its undersurface has a V-shaped indexing cutout 126, Which co-operates with a movable indexing roller 127, which, when it is moved into the indexing cutout 126, indexes the mandrel 43 to its exact rest position and retains it there.

Parallel with the mandrel shaft 112 is a vertically displaceable operating rod 128 for operating a holding finger 52 movably mounted on the mandrel 43. The holding finger 52 is provided at its upper end with a bearing 129 projecting at an angle from the finger, which bearing is pivotably supported in the lower end of the mandrel shaft 112, and is spring-loaded to urge holding finger 52 normally to press against the mandrel. At the upper end of the holding finger 52 there is also a projecting lip 130, which, when the mandrel 43 is in its rest position, is located immediately above a disc 131 at the lower end of the operating rod 128. When the operating rod 128 is raised the lip 130 moves upwards and the holding finger 52, against the action of the spring, is swung away from the surface of the mandrel 43.

On the operating rod 128 is also mounted the indexing roller 127 mentioned above. When the operating rod 128 is in its lowermost position the indexing roller 127 is spaced below the indexing sleeve 125. Whep,following rotation of the mandrel, the operating rod 128 is raised to lift the finger 52, the indexing roller 127 is also lifted upwards, into the V-shaped indexing cutout 126 in the indexing sleeve 125, and thus indexes the mandrel to its exact position. At the same time a release lip 132 located somewhat higher up on the operating rod 128 engages a roller 133 upon the brake arm 116 so that the brake shoe 115, counter to the action of the spring 117, is withdrawn from the brake disc 114, in order not to prevent correct indexing of the mandrel 43 to the exact rest position. At the upper end of the operating rod 128 is a helical spring 134 which urges the operating rod upwards to bear against a roller 136 (Fig. 19) which is freely rotatable at the end· of one arm of a bell crank lever 135. The bell crank lever 135 is pivoted in the upper part of the machine 37 and is connected by its other arm and a link 137 to one arm of another bell crank lever 138, of which the other arm carries a freely rotatable roller 139 riding against a cam 140 (hereinafter called finger cam) on the upper camshaft 32. The roller 139 is thus held by the spring 134 against the finger cam 140, and the operating rod 128 is shifted vertically upwards or downwards in accordance with the rotation of the cam 140 on the upper camshaft 32. More specifically, the operating rod 128 is lifted upwards to an upper position after each rotation of the mandrel caused by the rolling cam 123, (Fig. 18) as a result of Which the mandrel brake system 114—117 described above is inactivated, the mandrel is indexed to the exact rest position, and the holding finger is released so that the leading edge of the web 41 can be introduced.

Driver Unit.

The driver elenent 55 (Fig. 16) comprises a ring 141 which surrounds, and is movable in relation to, the cylindrical part of the mandrel. This ring is connected to a vertical shaft 142 axially movable, parallel with the mandrel, between an upper position (fully drawn lines in Fig. 16) and a lower position (dash-dotted lines in Fig. 16). For operation the upper end of the shaft '142 is attached to a vertical run of a toothed belt 143, which passes over guide pulleys 144, freely rotatable in the upper part of the machine 37. One end of the toothed belt 143 is connected to a lever arm unit 145, (Fig. 18) and the other end of the toothed belt 143 is connected to a return spring 146 (Fig. 18). The lever arm unit 145 is acted upon by a cam 147 (hereinafter called driver cam) on the upper camshaft 32, and the toothed belt 143 reciprocates the driver element 55 in its vertical path.

The lever arm 145 moves the driver element 55 between a fixed upper turning point and a variable lower turning point. This allows packaging containers of varying heights to be manufactured in the machine by appropriate choice of the width of the web 41. When a sleeve 4 of greater height than normal is on the upper part of the mandrel and is to be shifted downwards to the lower position in which its bottom end extends beyond the mandrel 43, the lower turning point of the driver element 55 is adjusted upwardly so that the edge region of the sleeve 4 extending beyond the lower end of the mandrel 43 is not excessively wide. This is achieved by adjustment of the lever arm unit 145 which comprises a primary lever arm 148, a secondary lever arm 149 and an intermediate lever arm 150 between them, the assembly being pivotably supported in a bracket 151. The bracket 151 carries two bearing shafts 152 and 153 to support the primary and the secondary lever arms 148 and 149 respectively. The bracket 151 also carries a vertically displaceable supporting block 154 with a shaft 155 which supports the intermediate lever arm 150. The two fixed bearing shafts 152 and 153 are spaced from one another in vertical as well as in horizontal directions and the shaft 155 is displaceable along a vertical path. The lower end is immediately above the bearing-shaft 153 and the upper end is closely adjacent (on the left in Fig. 18) to the bearing shaft 152.

During the operation of the machine, when the upper camshaft 32 rotates, the driver cam 147 displaces a roller 156 and the primary lever arm 148, to rock the arm about its pivot. This movement is transmitted to the secondary lever arm 149 by three rollers 158, 159 and 160 supported by, and freely rotatable on a common shaft 157 at the lower end of the intermediate lever arm 150. The middle roller 159 is acted upon when the primary lever arm 148 is pivoted by a flat surface 161 thereof, facing the roller 159. Subsequently the movement is transmitted by the shaft 157 and the two rollers 158 and 160 to two parallel vertical edge surfaces of the side limbs of the secondary lever arm 149 facing the primary lever arm 148 and abutting on the rollers 158 and 160. The movement of the secondary lever arm is then transmitted by a belt pulley 162 freely rotatable in the lower end of the secondary lever arm, to the belt 143, thereby actuating the driver element 55. When the lower turning point of the driver element 55 is to be adjusted, e.g. lowered, the supporting block 154 is shifted upwards. The transmission element consis ting of the shaft 157 and the rollers 158, 159 and 160 is thus moved closer to the supporting point of the secondary lever arm, so that the transmission ratio between the primary lever arm and the secondary lever arm is altered. The secondary lever arm thereafter performs a larger movement in response to a given movement of the primary lever arm, as a result of which the driver element 55 is given a greater stroke by the belt 143, and its lower turning point is set at a lower level.

The geometric relationship between the spacing of the bearing shafts 152 and 153 and the upper camshaft 32 is chosen so that the flat surfaces on the primary lever arm and secondary lever arm co-operating with the transmission element 157—160 are parallel with one another when the roller 156 of the primary lever arm 148 rests against the smallest - 27 4 4 ί, 3 radius of the driver cam 147, that is to say when the driver element 55 is in its upper .turning position. In this position a shifting of the transmission element does not therefore affect the secondary lever arm 149, and since the primary and secondary lever arms return to positions parallel with one another each time the roller 156 of the primary lever arm rides against the smallest radius of the cam 147, the upper turning position of the driver device is not affected by any adjustment of the transmission ratio between the lever arms, Hot-Air No2zle.

To facilitate the winding of each sheet 1 round the mandrel and its formation into a sleeve a hot-air nozzle 53 (Figs. 20, 21 and 22) is provided to heat the sheet on its path between the cutting device 51 and the mandrel 43. This nozzle 53 has a width substantially corresponding to the width of the sheet 1 and is connected by a flexible hose 171 to a source of hot air in the machine. The hot-air nozzle 53 is displaceably supported in a fixed bracket 172, which is provided with a guiding slot 173 extending towards the point of contact between the sheet 1 and the peripheral surface of the mandrel 43. Pegs 174, at the front end of the hot-air nozzle 53, are engaged in the slot 173 to slide therein when the front end of the hot-air nozzle 53 is moved towards and away from the sheet 1. To effect that movement the rear end of the nozzle is mounted in a fork 175, which is attached to a rotatable shaft 176, connected by a link 177 to a lever arm 178. The lever arm 178 is pivotably supported at its upper end on a shaft 179 fixed in the frame of the upper part of the machine 37, and the lever arm 178 is rocked by engagement of a roller 180, supported by and freely rotatable in, the lever arm 178, by a cam 181 on the upper camshaft 32. t A return spring 182 ensures that the roller 180 accurately follows the contour of the cam 181.

The hot-air nozzle 53 is shown in Fig. 21 in its inner position where the mouth of the nozzle projects into the angle between the sheet 1 and the cylindrical surface of the mandrel 43. In Fig. 22 the nozzle 53 is shown in its outer, inactive, position, where the hot-air jet from the continuously blowing nozzle is prevented from reaching the sheet by a jet-reversing element 183 which is pivoted into a position in front of the nozzle mouth. The jet-reversing element 183 is pivotably supported on a shaft 184 in the bracket 172 and a pin 185 at the side of the hot-air nozzle 53 facing the jet-reversing element, is so positioned that, on the withdrawal movement of the nozzle, it actuates an adjustment screw 186 at the rear end of the jet-reversing element 183, so that the jet-reversing element 183 is turned about the shaft 184 in clockwise direction (Figs. 21 and 22) with its front end pivoting in front of the mouth of the hot-air nozzle 53 to break tho jet.

The hot-air nozzle 53 is operated between its aotive and its inactive position in attendance with the rotation of the mandrel 43. When the holding finger 52 co-operating with the mandrel 43 in the standstill position of the mandrel embraces ahd retains the leading edge of the sheet 1, the hotair nozzle 53 is ih its rear, inactive position. At commence25 ment of rotation of the mandrel, the hot-air nozzle is moved by the cam 18 to its inner position and, during the complete rotation of the mandrel, it heats the passing sheet immediately before the sheet is wound round the cylindrical surface of the mandrel. When the sheet has been almost fully wound round the mandrel, the rotation of the mandrel is stopped, as mentioned earlier, for a brief period during which the two short end zones of the sheet are in the path S 4*433 of the jet from the hot-air nozzle. As a result the end edge zones are heated to the softening temperature of the plastics material, to be heat-sealed to each other along a longitudinal joint 5. After this intensive heating the nozzle is returned again to its withdrawn position.

Sleeve-Forming Unit.

When the sheet 1 after being cut from the web 41, and following heating by the hot-air nozzle 53 is to be wound round the mandrel to form a sleeve 4, it is held closely against the cylindrical mandrel surface by a sleeve-forming element 54 located adjacent to the mandrel, as will be described in greater detail with reference to Figs. 23 and 24. The sleeve-forming device 54 is supported by a vertical shaft 187, which is rotatably mounted in the upper part of the machine 37 and is provided at its upper end with a lever arm 188 connected by a link 189 to one arm of a bell crank lever 190. The other arm of the lever 190 carries a freely rotatable roller 191 held by a spring 192, acting on the bell crank lever to ride against and accurately to follow the contour of, a further cam 193 on the upper camshaft 32. The shaft 187 supporting the sleeve-forming device 54, during operation of the machine, is rotated in a reciprocating movement under the control of the rotating cam 193. The shaft 187 extends substantially parallel with the axis of the mandrel 43 and at its lower end, is a lever arm 194 nonrotatably fixed to the shaft 187. The shaft 187 is located adjacent to the area of the mandrel 43 on which the sleeve is formed. The lever arm 194 is provided, adjoining its outer end, with a shaft 195, parallel with the axis of the mandrel 43 which pivotably supports a holder 196 extending substantially at right angles to the lever arm 194, towards the mandrel 43. The outer end of the holder 196 terminates adjacent to the mandrel 43 and supports a vertical shaft 197 which supports a controlled pressure device 198. The shaft 197 also carries a roller 199 against which bears a leaf spring 200 fixed to the outer end of the lever arm 194. The spring 200 acts to urge the holder 196 pivotally about the shaft 195. To rest against an adjusting screw 202 in a lug 201 on the lever arm 194. The pressure device 198 at the outer end of the holder 196 consists of two spaced parallel plates 203, which are pivotably supported by a pin 197, respectively on the upper and lower sides of the holder 196. The plates'203 are substantially triangular and are connected to one another at the three corners, namely at the first corner by the said shaft 197; at the second corner by a longitudinal joint compression device 204, fixed between the two plates 203, and provided with a cambered compression surface 205; and at the third corner by a further vertical shaft 206 which supports a roller axially parallel with the roller 199. The shaft 206 extends a little above the surface of the upper plate 203, and the projecting part serves as a pivot bearing for one end of a link 208, the other end of which is rotatably connected with a vertical rod 209 which at its upper end is fixed to the upper part of the machine 37. The sleeve-forming element 54 is pivotable by the shaft 187 between three positions determined by the cam 193, namely a first position in which a compression roller 207 and the compression device 204 are spaced from the mandrel 43; a second position in which the leaf spring 200 urges the compression roller 207 to ride against the mandrel; and a third position in which the compression roller 207, and the compression surface 205 of the compression device 204, bear against the mandrel.

The operation of the sleeve-forming device 54 moving between the above-mentioned three positions, and the cooperation of the mandrel 43, the sleeve-forming device 54, the holding finger 52 and the hot-air nozzle 53 are illustrated in Figs. 25—31, which show step-by-step the formation of a sheet 1 into a sleeve 4 provided with a longitudinal joint 5.

In Fig. 25 the co-operating devices are shown at the instant when the leading end of the web 41 is advanced to the mandrel. The leading edge of the web has not yet been clamped between the mandrel 43, and the holding finger 52 (which finger is shown in its inactive position spaced from the mandrel).

The hot-air nozzle 53 is in its withdrawn, inactive, position. The sleeve-forming device 54 is in its swung-back, first, position in which neither the compression roller 207 nor the compression surface of the pressure device 198 bear against the mandrel 43. The holder 196 of the sleeve-forming device 54 is pressed by the spring 200 against the adjusting screw 202.

In Fig. 26 the leading edge of the web has been gripped to the peripheral surface of the mandrel 43 by the holding finger 52, which has been moved to its active position. The hot-air nozzle 53 has also been moved to its inner, active, position and the heating of the web has started. The mandrel rotation, and the pivoting forwards of the sleeve-forming device 54 to the second position are about to be started.

At this moment the cutting device performs a working stroke (as described above with reference to Figs. 11—15) and a foremost length of the web is cut off to form a sheet 1.

Its length somewhat exceeds the circumference of the mandrel 43.

In Fig. 27 the mandrel commences to rotate, anticlockwise 4453 _ 32 ~ as seen, so that the cut-off sheet, which is heated continuously by. the hot-air nozzle 53 in its working position, commences to be wound round the mandrel. The forming element 54 at the same time is pivoted clockwise to its second position in which the . compression roller 207, acted upon by the spring 200, urges the sheet against the cylindrical surface of the mandrel 43 during,its rotation.

In Fig 28 the sleeve-forming device 54 is shown in its second position and the forming of the sleeve 4 proceeds IO during continuous heating by the hot-air nozzle 53.

In Fig. 29 the forming of the sleeve 4 has been virtually completed and the mandrel arrested in such a position that the two overlapping ends of the sheet wound round the mandrel are directly exposed'to the hot air from the nozzle 53. The nozzle, as well as the holding finger, are in their active . positions and the sleeve-forming device . 54 remains in its second position.

In Fig. 30 the hot-air nozzle has been returned to its withdrawn, inactive, position and the sleeve-forming element 54, by virtue of a further pivoting, in clockwise direction, of the shaft 187, has been moved to its third position, in which the pressure device 198 is turned by the link 208, clockwise so that the compression surface 205 is pressed strongly against the overlapping end edge zones of the sheet, heated up to softening temperature, so that they are bonded together to form a longitudinal joint.

In Fig. 31 the sleeve-forming device 54 is shown during its return movement to the starting position, while the mandrel 43 is rotated to the rest position. The hot-air nozzle 53 continues in its inactive position and the holding 463 finger 52, when the mandrel reaches its rest position, releases the sleeve 4, which thereafter, as described earlier, is pushed downwards to the bottom end of the mandrel 43 in order to make room for the subsequent sheet 1 and a repeat of the forming cycle described.

Lower Machine Section: Devices for the Feed and Cutting of the Container Base.

The base blanks 6 are supplied to the machine, as mentioned previously, in the form of a continuous strip 45 of octagonal blanks 6. The strip runs from a magazine roll 44, supported rotatably in the roll stand 39, over guide pulleys and control devices, (not shown) to the base feed wheel 76 (Fig· 32) which is located in the vicinity of the lower end of the mandrel 43, and is supported by a horizontal shaft 210 (on which it is freely rotatable) in the lower machine section 38. The base feed wheel 76 is hexagonal and comprises six flat surfaces 211, each substantially square and of a size which substantially corresponds to the size of each base blank 6. At the edges between adjacent flat surfaces 211 the base feed wheel 76 is provided with drivers 212 each in the form of a knife edge extending parallel with the shaft 210. Each driver 212 is provided at its central part with a cutout 213, the width of which somewhat exceeds the width of the strip 45 at the junctions between the blanks.

In operation the base feed wheel is rotated step-bystep in the direction of the arrow 214 and the strip 45 is advanced by substantially one half turn of the periphery of the wheel, so that it is fed into the cutting element 56 adjacent to the upper part of the wheel. The strip is guided along its path by a guiding channel 215 preceding the base 44453 - 34 feed wheel 76, and the strip is retarded by a brake spring 216, which also ensures that the strip is 3cept flat and straight. The strip 45 is guided round the base feed wheel 76, in engagement with the drivers 212, by a flexible band 217, one end of which is fixed in the machine frame above the base feed wheel 76. From this; fixed point the band runs around approximately l/3rd of the periphery of the wheel and is attached : at its other end to the machine frame by a spring 218. At the upper part of the base feed wheel 76, the band IO 45 leaves, the .wheel and runs on to a stationary flat surface .219, at the end of which is the cutting element 56. The cutting element 56 comprises7 a stationary knife 220, and a cooperating vertically movable knife 221. At a distance from the cutting element, which corresponds to the length Of one base blank 6, there is a resilient stop 222. Between the cutting element 56 and the stop 222 is the base transfer device 57,(also shown in Figs. 33 and 34). This comprises a pivoted arm 223 which at one end is attached to a horizontal shaft 224, rotatably supported in the machine frame. At 2o its Other end the arm Z23 carries a suction head 225 which oh pivoting of the arm 223 round the axis of shaft 224, is movable between a first position (Fig. 32) between the cutting element 56 and the resilient stop 222, and a second position (Fig. 34) in contact with the end surface of the mandrel 43.

. Each time the feed wheel 76 is rotated by l/6th of a turn in the direction of the arrow 214, the strip 45 is fed forwards by a distance corresponding to the length of a base blank 6, and the front edge of the strip 45 comes into contact with the stop 222. Since the distance between the stop 222 and the cutting element 56 corresponds to the length of one blank 6, the co-operating knives 220 and 221 on activation sever the leading blank situated in this position from the remainder of the strip 45. During the feed of the strip towards the stop 222, and the severing of the leading blank, the transfer arm 223 is in the position shown in Fig. 32, and after the severing of the leading blank 6, the detached blank is retained by the suction head 225 on the transfer arm 223, which pivots about the shaft 224 and transfers the blank to a position of rest against the lower end of the mandrel 43.

The drive of the wheel 76, the cutting element 56 and the base transfer element 57 is illustrated in Fig. 33. The feed wheel 76 and the cutting element 56 are driven by a common cam 226 on the lower camshaft 29. The contour of the cam 226 is followed by a roller on a lever 227 pivotably supported in the frame of the lower machine section 38, one end of which lever is loaded by a spring 228 to ensure contact with the cam 226. The other end of the lever 227 is connected by a link rod 229 to one arm of a pivoted lever 230. Between the junction of the link rod 229 with the lever 230, and the supporting shaft 231 of the lever, the lever is provided with a laterally projecting freely rotatable, roller 232.

At the outer end of the other arm of the lever 230 is a corresponding roller 233. The lever 230 is connected by this roller 233 to a lever arm 234, which is firmly connected to the shaft 210 of the feed wheel 76, and more particularly the roller 233 is adapted to run in a longitudinal track in the lever arm 234. At the outer end of the shaft 210 the base feed wheel 76 is supported by a combined unidirectional drive and locking coupling, which, when the shaft 210 is driven in a reciprocating movement, ensures that the feed wheel is advanced step-by-step l/6th turn in anti-clockwise direction (as seen in Fig. 32). t In the close vicinity of the lever 230 is a further lever 235 of which the end remote from the lever 230, is acted upon by the roller 232 during rotation of cam 226. The end of the lever is connected by a link 236 to the movable knife 221 (Fig. 32) and the link rod 236 holds down the knife under the action of a spring 237 acting upon the lever 235.

On rotation of the lower camshaft 29 the cam 226 imparts to the lever 230 a pivoting movement between the position Illustrated in Fig. 33, and a position in which the lever has been rocked by approximately l/5th of a turn in clockwise direction. When the lever is thus rocked, the roller 233 at the upper end of the lever 230 acts upon the lever 234 to turn the shaft 210 anti-clockwise, and the shaft 210 advances the base feed wheel 76 one step. When the lever 230 approaches the end of its clockwise rocking movement, the roller 232 on the lever 230 comes into contact with one end of the lever 235 and lifts the lever against the action of the spring 237. The lifting movement is transmitted by the link 236 to the lower knife 221 of the cutting element 56, which in co-operation with the fixed knife 220, by a scissorlike operation, severs the newly advanced base blank from the leading end of the strip 45. During the return, anti-clockwise, swing of the lever 230 which follows, the knife 221 is returned to its lower inactive position by the spring 237. At the same time the roller 233 returns the lever arm 234 to the position shown in Fig. 33, which, because of the unidirectional coupling between the feedwheel and the shaft 210, does not affect the feedwheel.

The lever arm 223 of the base transfer device is opera30 ted by a further cam 281 (Fig. 33) on the lower camshaft 29.

The periphery of the cam 281 acts upon a roller 282 rotatable ( at one end of a pivoted lever 283, mounted in the frame of the lower machine section 38. The other end of lever 283 is connected to a toothed belt 284 tensioned by a spiral spring, which holds the roller 282 in contact against the peripheral surface of the cam 281. The toothed belt 284 runs over a pulley 285, fixed on the shaft 224 which carries the lever arm 223 of the base transfer device 57. When the cam 281 rotates the belt 284 receives a reciprocatory pulse, which through the pulley 285 and the shaft 224 imparts a rocking movement to the lever 223. This movement is synchronized with the base feed and severing operations so that the feed and the severing always takes place with the lever arm 223 in the position shown in Fig. 32.

Shrinking and Base-Forming Unit The movable shrinking and base-forming unit 79 and the means for moving it between different working positions are illustrated in Figs. 35—39. As mentioned earlier, the shrinking oven 58, the base-forming or base-assembling device 59 and the gripping element 60 are combined as a unit 79 which is movable both horizontally and vertically. The unit is located underneath the mandrel 43 and has three functions, namely, in the first place, to heat the sleeve 4 and the base blank located at the bottom end of the mandrel; secondly, immediately after the heating to press together the shrunk-in edge of the sleeve with the base blank,and thus to form the base of the container; and thirdly, after the base-forming to transfer the container from the bottom end of the mandrel 43 to the intermittently operating conveyor chain 25 running adjoining to the mandrel. For the unit 79 to carry out these functions it is displaceable in a horizontal direction so that each o£ the elements included in the unit can as required be - 38 brought into line with the mandrel. Furthermore the shrinking oven 58 and the assembling device 59, when they have been brought into line with the mandrel, are movable vertically upwards to a working position. The shrinking oven 58 and the base-assembling device 59 can be moved independently of each other in a vertical direction, and the displacement of the unit in a vertical direction and horizontal direction is effected respectively by two separate cams 238 and 239, each of which is mounted on the lower camshaft 29.

As seen in Fig. 36 the shrinking oven 58 comprises a tubular upper part 240 provided with an air heating unit, which by a concentrically connected tube 241 is attached to a supply line 242 for air. Immediately below the tubular part of 240 the tube 241 is provided with two freely rotatable rollers 243 opposite one another. Between the lower end of the tubular part 240 and a laterally projecting bracket 244 fixed to the bottom end of the tube 241, extends a guide rod 245 which is parallel with but spaced from the tube 241. On the inner cylinder of the tubular part 240 is a third bracket 247 which carries two fingers 248 and 249, pivotably in a horizontal plane which form the cup-gripping element 60 described earlier.

Parallel with the shrinking oven 58 is the base-assembling device 59 comprising a vertical shaft 250 at the upper end- of which is an adjustable disc 251. The lower end of the shaft 250 is connected to a guide tube 252 which like the shrinking oven 58 is provided with two freely rotatable rollers 253.

The tube 252 comprises an arm 254, extending towards the shrinking oven and at its outer end is supported but vertically slidable on the guide rod 245. The shaft 250 of the baseassembling device 59 is likewise vertically slidable in its supporting bracket 246. ι 4 453 The unit consisting of the shrinking oven 58, the baseassembling device 59 and the cup-gripping element 60 is supported by one arm of a bell-crank lever 255 which is rockably mounted on the shaft 256 in the lower machine section 38.

This supporting arm of the bell crank lever 255 is fork-like and the arms of the fork are provided on their facing surfaces each with a longitudinal track 257, the tracks being located opposite one another and extending substantially horizontally. The roller pairs 243 and 253 of the unit 79 are run in these tracks. The tracks 257 terminate at the outer end of the lever arm, and at a point along its length each track 257 communicates with a vertical gap 258 opening below the lever arm. The other arm of the bell crank lever 255 is provided at its outer end with a roller 259 which is held by a spring to ride against a cam 239. On rotation of the lower camshaft 29 the unit 79 is raised and lowered by the bell crank lever 255 in accordance with the shape of the cam 239. The unit 79 is not displaced in horizontal direction by this movement, but the two roller pairs 243 and 253 are free to move along the track 257.

To control displacement of the unit in horizontal direction a travelling crab 260 (Fig. 35) which is supported and horizontally movable on a horizontal guide bar 261 incorporated in the lower machine section 38. The crab 260 is connected at its side facing the lower camshaft 29, to one arm of a control lever 262, which carries a freely rotatable roller 263 held by a spring 264, acting upon the other arm of the lever, against a cam 238 on the lower camshaft. The crab 260 thus performs a horizontal reciprocating movement in accordance with the rotation of the lower camshaft 29 and the cam 238.

The crab 260, in turn, displaces the unit 79 (consisting of - 40 the shrinking oven 58, the base-assembling device 59 and the gripping element SO) causing it to slide along the track 257 in the bell crank lever 255 following the movement of the crab 260. To achieve the result the tube 241 connected to the shrinking oven 58, the rod 245, and the base-assembling device 59 are supported, but vertically reciprocable in a shell of the crab 260 extending underneath the horizontal arm of the bell crank lever 255 (Fig. 35). The movement of the crab 260 in horizontal direction is thus transmitted directly to the unit, although the crab has no function to move the elements in the unit in vertical direction.

The sequence of movements of the unit consisting of the shrinking oven 58, the base-assembling device 59 and the gripping element 60 during operation of the machine will now be described in detail with reference to Figs. 36—39, which illustrate, step-by-step, different successive positions of the Unit. In Fig. 36 the horizontal arm of the bell crank lever 255 is in a lower position, in which the shrinking oven 58, the base-assembling device 59 and the gripping element 60 are supported at a distance beneath the lower end of the mandrel 43. Horizontally the unit is in its mid-position, that Is to say the position in which the shrinking oven 58 is axially in line with the mandrel 43. In this indexing position the shrinking oven 58 is supported by engagement of the two rollers 243 in the track 257 of the bell crank lever while the rollers 253 of the base-assembling device 258 are over the vertical gap of the track 258 in the bell crank lever and thus afford no support for the base-assenibling device, which however rests for support upon the attachment 252 and the horizontal shelf of the crab 260. In the gripping device 60 located near the upper end of the shrinking oven 58 is shown a container 265 completed during the immediately preceding working cycle, while the mandrel 43 carries at its bottom end a sleeve 4 and a base blank 6, which are to be formed into a container during the working cycle which will follow.

In Fig. 37, the arm of the bell crank lever 255 has been pivoted to an upper position by rotation of the cam 239. Horizontally the unit 59 remains in the mid-position shown in Fig. 36, and the bell crank lever has lifted the shrinking oven 58 to a working position where the upper part of the oven surrounds the bottom part of the sleeve 4 on the mandrel 43, as a result of which the hot air flowing through the shrinking oven 58 heats and shrinks the sleeve 4 as well as heating the base blank 6. The base-assembling or finishing devide 59, is not lifted since its roller pair 253 is in line with the vertical gap 258, and it remains in the position shown in Fig. 36 with the attachment 252 resting on the upper surface of the horizontal shelf of the crab 260. After a predetermined time required for the heating of the sleeve 4 and the base blank 6 the bell crank lever is pivoted anticlockwise so that the groove 257 is again in a horizontal position and the shrinking oven 58 is lowered into the position shown in Fig. 36.

Upon the return of the arm of the bell crank lever 255 to the position shown in Fig. 36 the open end of the track 257 comes into line, with a bracket 266, supported by the frame of the lower machine section 38, in which bracket is provided a corresponding horizontal track 267. While the track 257 is aligned with the track 267 an indexing of the unit 59 is effected (one step to the left as seen in Fig. 36).

The rollers 243 of the shrinking oven 58 enter the fixed track 267 (Fig. 38) while the base-assembling device 59 is - 42 moved to a position beneath and axially aligned with the mandrel 43. Furthermore, the indexing of the unit moves the gripping element 60 into co-operation with the transport chain 25 (Fig. 40) to deliver to the chain the complete container 265 which it supports (Fig. 36). After the indexing of the unit, the bell crank lever 255 is rocked again in clockwise direction to an intermediate position or base-finishing position, (Fig. 38) where engagement of the two rollers 253 in the track 257 results in the lifting of the base-assembling device 59 so that the disc 251 at the top end of the rod 250 makes contact with and presses the base blank 6 and the shrunk in annular edge zone of the sleeve 4 (Fig. 38). After the assembling and forming of the container on the mandrel 43 has been completed and the container formed previously has been transferred to the transport chain 25, the bell crank lever is pivoted anti-clockwise to the lower position shown in Fig. 39.

When the track 257 of the bell crank lever reaches the horizontal position in line with the track 267 in the bracket 266, an indexing of the unit (which includes the shrinking oven 58, the base-finishing device 59 and gripping element 60) to the right as seen in Fig. 39), takes place. The unit reaches a position wherein the gripping element 60 is axially in line with the mandrel 43 (Fig. 39). When the unit has reached this position, the driver element 55 is moved downwards and displaces the next sleeve 4* (Fig. 39) formed during the above-described working cycle from an upper to lower position on the mandrel. The lower edge of the sleeve 4' comes to rest against the upper edge of the completed container and the completed container is pushed downwards into the gripping element 60 and retained between the sprihg- 43 44453 loaded fingers 248, 249 thereof. The unit is finally indexed again into the position shown in Fig. 36 for heating of the next sleeve, whereafter the cycle is repeated.

Fig. 40 illustrates the transfer of a completely formed container from the gripping element 60 mounted on the shrinking oven 58 to the transport chain 25 which moves intermittently in the direction of the arrow 268 and transfers the containers to the filling machine 13. The transport chain 25 comprises a chain 269 which carries at its under-side U-shaped holders 271 of which the open sides face towards the gripping element 60 supported by the shrinking oven 58.

The gripping element 60 comprises, as mentioned earlier, two fingers 248, 249, supported so that each can pivot horizontally about a vertical pin 272. The fingers 248, 249 are actuated between a closed position, where the fingers embrace and retain a container between them, and an open position where the fingers are separated from one another. These two finger positions are determined by a projection 273, at the rear part of the fingers and extruding sideways, which cooperates with springs 274 and sits the fingers in either of the two positions.

The change-over of the fingers 248, 249 from the closed to the open position and vice versa occurs as the gripping element 60 is introduced to and withdrawn from the transport chain 25 respectively, and is controlled by means of two vertical pins 275, 276, which are in stationary positions at a slight distance from the transport chain 25 and spaced from one another by a distance which somwwhat exceeds the width of the gripping element 60. When the gripping element 60 holding a completely formed container is moved to the transport chain 25 as a result of indexing of the unit, the lower ends of the λ. 4453 - 44 two pins 275, 276 co-operate with a stop 277 projecting at the rear end of the fingers 248, 249, at substantially a right angle from the fingers, as a result of which the fingers are swung to the open position in which they are retained by co-operation of the projection 273 with the springs 274. The completely formed container has now been transferred to and is carried by the holder 271 of the transport chain 25.

When the gripping element 60 is withdrawn from the transport chain, (that is to say, moved to the right in Fig. 40) the pins 275, 276 no longer act upon the stop 277 of the arms. The arms remain, however, in the open position, retained by the projection 273 and the springs 274 until the fingers 248, 249 have been virtually withdrawn from the transport chain 25. At the end of the return of the gripping element 60, shoulders 278, located at the outer end of the fingers 248, 249, are acted on by pins 275, 276, and the fingers, against the effect of the springs 274, are returned to the closed position and the gripping element 60 is ready to receive the next completely formed container.

Filling Apparatus Section.

The transport chain 25 now transfers the formed containers to the filling apparatus 13 and the containers are transferred from the part of the transport chain 25 moving transversely across the conveyor 15 of the filling apparatus, by elements provided with suction heads. The containers are deposited in apertures 16 in one of the transverse lines of the conveyor 15. When a segment of the conveyor has been filled with containers, each open at the top, the conveyor 15 is advanced one step so that the next, not yet filled, segment is located underneath the transport chain 25. After a number of indexings, the first-mentioned segment, filled with containers has reached a position beneath a filling unit 46 (Fig. 2) located above the filling apparatus. The filling unit may comprise a reservoir 279 for the material to be packaged, and a number of filling pipes 280 running vertically downwards from the reservoir and provided with shut-off valves. The number of filling pipes 280 corresponds to the number of pockets 16 disposed transversely across the conveyor 15 in each line. Control devices, which may be of a kind wellknown to anybody versed in the art, control the valves of the filling pipes 280, which are then opened for such a time that the containers in the conveyor 15 are filled with contents to the desired level.

By further indexings of the conveyor 15 the filled row of containers then reaches a lid unit 47, which like the filling unit 46 is located above the upper part of the conveyor 15 The lid unit 47 now punches out a number of lids 9 from a web running between the lid material roll 48 and the unused or waste roll 36, of which the width substantially coincides with the width of the conveyor 15. The punched-out lids 9 are heated and thermoformed subsequently so that they assume the desired shape, with a substantially flat central flat 10 and a flange 11 surrounding this area. By heating the upper edge area of each container and the flange 11 of a lid 9 to the softening temperature of the material, and subsequent application of the lids 9 to the containers each lid is then bonded to a container to form an impervious seal.

By a number of further indexings of the conveyor 15 the filled and closed containers then reach a station at which they are withdrawn from the pockets 16 of the conveyor 15 to be further transported by a chute 49, to the required station, for example for packing into larger collective carriers.

The machine in accordance with the invention comprises, - 46 in addition to the above-mentioned devices and details, also a large number of conventional elements, e.g. brackets, attachment elements, pneumatic valves and others which are, however, of a well-known type and do not require any more detailed description. The toothed belts which are used for the driving of the different elements can be replaced by other powertransmitting elements, e.g. chains or any other element which within the scope of the following claims can be substituted for other equivalent elements.

In the lower machine section 38 fans and heating units for the generation of the hot air used In the hot-air nozzle 53 and the shrinking oven 58 are also indicated on the left in Fig. 2. Above the lower camshaft 29 the programming mechanism 33 is further arranged which, for a number of cams arranged on the camshaft 34 in conventional manner, acts upon micro-switches. The micro-switches are used for the control of certain functions in the machine e.g. for keeping the pattern in register during the feed of the web 41; and controlling the vacuum and pressure in the mandrel ducts 165 and 166.

It should be emphasized that the described forming process is continuously repeated and that the immediately preceding or following forming processes partly overlap, and take place at the same time as the forming process described. Thus, for example, the shrinking of a sleeve located at the bottom end of the mandrel takes place at the same time as the mandrel rotation and the forming of the subsequent sleeve, ahd likewise the transfer of a completed container to the transport chain 25 takes place simultaneously with the base formation of the subsequent container.

For a repetition of the above description of this - 47 44433 invention, accompanied by claims to features different from those recited in the claims following this description, reference is made to Patent Specification Nos. 44452 and 44453.

Claims (13)

1. CLAIMSιΙ. A container forming and filling machine comprising a mandrel shaped to define the internal container shape, means for shrink-forming a sleeve of heat-shrinkable material to container form on said mandrel, apparatus for filling a container with desired contents, and means for transferring a container formed on said mandrel to the filling apparatus.

2. A machine as claimed in Claim 1 wherein said filling apparatus comprises a filler conveyor, and an endless conveyor delivers a completed container to said filler conveyor.

3. A machine as claimed in Claim 2 wherein said endless conveyor runs transversely of the filler conveyor along the length of its run from which it delivers the container to the filler conveyor.

4. A machine as claimed in Claim 2 or 3 comprising means to transfer a container from the mandrel to said endless conveyor.

5. A machine as claimed in any of Claims 1—4 wherein said filling apparatus, and said means for shrink-forming a sleeve and said means for delivering a container to said filling apparatus are driven in synchronism.

6. A machine as claimed in Claim 5 wherein all said means and said apparatus are actuated by a common drive.

7. A machine as claimed in Claim 5 wherein all said means and apparatus are actuated intermittently.

8. A machine as claimed in Claim 2 or in any of Claims 3—7 when appendant to Claim 2 comprising suction means to assist delivery of a container to said filler conveyor.

9. A machine as claimed in Claim 2 or in any of i 4453 Claims 3—8 when appendant to Claim 2 wherein said filler conveyor is formed with a plurality of apertures each adapted to receive a container.

10. A machine as claimed in any preceding claim 5 comprising means for applying a lid to a container after filling.

11. A container forming and filling machine as claimed in any preceding claim comprising a plurality of mandrels with means for simultaneously forming containers 10 thereon, and conveyor means for simultaneous delivery of said plurality of containers to said filling apparatus.

12. A machine as claimed in Claim 11 wherein said filling apparatus comprises a filler conveyor adapted to receive a plurality of containers in line transversely of

13. 15 its length.