US 3659394 A
A method and machine for wrapping articles with sheet material involves withdrawing the sheet material from a supply reel and leading it into engagement with the article and thereafter setting the article into rotation so as to entrain the sheet material and wrap the material about the article. The method and machine is useful for packaging and labelling articles.
Description (OCR text may contain errors)
United States Patent Hartleib et al.
[ 1 May 2,1972
 METHOD OF AND MACHINES FOR WRAPPING ARTICLES  Inventors: Franz Hartleib, Furstenau; Herbert Windelbandt, Aachen, both of Germany Firma Maschinenbau Aachen-Furstenau Gesellschaft mit beschranketer Haftung, Reichsweg, Germany  Filed: Nov. 12, 1969 l2l] Appl.No.: 875,754
[30 1 Foreign Application Priority Data Nov. 16, 1968 Germany ..P 18 09 270.1 Oct. 4, I969 Germany ..P 19 50 226.2
 US. Cl ..53/33, 53/214, 53/216, 156/568  Int. Cl. ..B65b 11/0, B65b 49/16, B65c 9/00 [58} Field ofSearch ..53/21l-216,32, 53/33, 209; 156/568  References Cited UNITED STATES PATENTS 1,108,027 8/1914 Thorschmidt ..53/2l5 2,643,499 6/1953 Gerlach ..53/2l4 X 2,938,319 5/1960 Nystrand....
2,952,105 9/1960 Schur.....
3,035,379 5/1962 Cloots 3,056,246 10/1962 Lyon et al ..53/234 X FOREIGN PATENTS OR APPLICATIONS 805,139 5/1951 Germany ..53/2l6 Primary Examiner-Theron E. Condon Assistant Examiner-Neil Abrams AltorneyArthur O. Klein [5 7] ABSTRACT A method and machine for wrapping articles with sheet material involves withdrawing the sheet material from a supply reel and leading it into engagement with the article and thereafter setting the article into rotation so as to entrain the sheet material and wrap the material about the article. The method and machine is useful for packaging and labelling articles.
31 Claims, 10 Drawing Figures F'ATENTEUMAY 2 1972 SHEET 2 BF 6 ATToRpo/ PATENTEDW 2:912 3,659,394 sum 60F 6 FRHML H LElB Heabekr LUWDLE BANDT' llrmanev METHOD OF AND MACHINES FOR WRAPPING ARTICLES The present invention relates to a method of and to machines for completely or partially wrapping articles to package or label same.
An object of the present invention is to create a high performance method and machine for the implementation of said method, enabling accurate packaging of single articles (and also of collective packs or packages of articles) of cylindrical or approximately cylindrical external peripheral form, this at a high rate and using means of simple construction. In addition to the complete or partial wrapping of articles, the method and the machine used to implement it, are intended to make it possible to carry out labelling and similar operations which, in the following, are intended to be generally included in the concept of wrapping. Furthermore, the method should permit the use of all conventional packing materials such as shrinkable and non-shrinkable thermoplastic foils, hot-sealing cellophane, viscose foil, paper, composite materials and so on.
Commencing from the use of sheet material in the form of a web which is drawn from a supply reel and taken to the article being wrapped (the term article as used here is intended in the following to include a composite article made up of a bundle of articles), the method of the invention is primarily characterized in that the article being wrapped is set into rotation in engagement with the sheet material and by entraining the said material thus automatically wraps same around its own external periphery. Preferentially, the sheet material, prior to engagement with the article being wrapped, will be fed over a support for said article and the article itself, while in engagement with the sheet material, imparted a predetermined translatory movement by said support directed transversely of the axis of rotation of the article itself, this before said article is set into rotation. To this end, the article being wrapped can be passed by a fixed abutment cooperating with its external periphery, and set into rotation while in engagement with said abutment, on the one hand, and with the sheet material, on the other. Instead of this, after covering a predetermined length of translation, a section can be parted ofi from the web before the article is set into rotation to be wrapped by the section.
The method in accordance with the invention ensures a continuity in the movements of the articles being wrapped, during the wrapping operations, and this enables the operation to be run continuously so that wrapping performances of hitherto unattainable level are achieved. The article being wrapped in a first embodiment automatically measures off the quantity of material required for wrapping, and this, in association with the tight wrapping of the article, achieves substantial economies in material and the range of variation to accord with articles of varying sizes is substantially enlarged without requiring any appreciable amount of readjustment work. The tight wrapping of the articles in numerous cases makes it possible to dispense with the use of shrinkable packing materials, while at the same time the displacement of packaged articles within a wrapping is counteracted. Because of the facility for multiple wrapping of articles, it is possible furthermore to use wrapping materials of low strength. In a second embodiment, a rotating wrapping movement on the part of the articles being wrapped is produced independently of any web withdrawal operation. Of course, this means that the sections of sheet material must be adapted in length to the dimensions of the articles being wrapped, however it means that the rotary wrapping operation is free of any tensile forces of the kind otherwise required for drawing the web from its supply reel. The fact that the rotary wrapping movement is independent of any web withdrawal function, furthermore makes it possible to determine the angular speed of the rotary wrapping movement independently of considerations associated with such web withdrawal function. The provision of an independent feed, also a feature of the invention, for the web, at a feed rate which is adapted to the speed of the feed feet rapid and simple adjustment and modification of the prescribed length of web sections, to accord with varying dimensions in the articles being packed. The accuracy of the matching of the wrapping material to the article being packed, ensures accurate positioning of longitudinal perforations, markings etc. in relation to the article, and opens the possibility of using purpose-printed material so that even when shrinkable foils are used there is no appreciable distortion of the print.
The machine for implementing the method is primarily characterized by a conveyor which moves supports for articles being wrapped, along an endless path, by an abutment arrangement assigned to said conveyor along part of its path of movement, in order to derive a rotational movement for the articles being wrapped, which are carried by their supports, and by a transverse cutting or shearing arrangement assigned to the conveyor in or before the zone over which the abutment arrangement extends, which cutter device, in adaptation to the movement of the conveyor cuts a section from the web of material, the latter moving forward in engagement with the supporting arrangements and the articles being wrapped,olf the supply reel.
The machine is distinguished by a simple, compact and reliable construction, which enables the wrapping performance to be increased to several times that possible with known wrapping machines. Despite its high speed of operation, the machine requires only a relatively small drive power, makes it possible within certain limits to accommodate variation in the articles being packed without any special steps being required, and also opens up the possibility, depending upon the width dimension of the supporting arrangements, to simultaneously wrap several individual articles in a combined multiple cycle. The operation of the machine is simple in particular with a view to straightforwardness of supply and discharge of the articles prior to and after the carrying out of the wrapping operation, and, because of the reduction in the operating requirement, introduces substantial savings in labor charges.
Numerous other features and advantages of the invention will be apparent from the claims and the description taken in conjunction with the accompanying drawings, in which latter several examples of the invention have been illustrated in more detail:
FIG. 1 illustrates a very simplified schematic side elevation of a first embodiment of a packing machine in accordance with the invention;
FIG. 2 is a view similar to that of FIG. 1 of a second embodiment;
FIGS. 3a and b schematic side elevations of a third embodiment of a packing machine in accordance with the invention;
FIG. 4 is a simplified section of the line IV-IV of FIG. 3a;
FIG. 5 is an enlarged side elevation of a fragment V of FIG. 3a;
FIG. 6 is a fragmentary view similar to FIG. 5, depicting the application of the front end of a web of material, to the front face of an article being packed;
FIGS. 7 to 9 illustrate partial side elevations of the machine in FIG. 3a, showing modifications of the machine in order to adapt it to the packaging of differing articles.
In the drawing equivalent parts are designated whenever possible with the same reference numerals in the various illustrated embodiments.
The machine shown in FIG. 1, comprises a conveyor marked in toto by 1, rotating at a steady speed about a fixed horizontal axle 2, the conveyor taking the form of a drum. In detail, the conveyor drum 1 exhibits two twin carriers each arranged at one end and each consisting of two single carriers 3,
mounted coaxially upon a common carrier shaft 4. In the drawing, it is only the single carrier 3 (presenting one end to the observer) of the front twin carrier, which is fully visible, and behind this, in line with it in the direction perpendicular to the plane of the drawing, there is a corresponding single carrier which belongs to the twin carrier located at the distant end movement of the support, in particular makes it possible to ef- (considered in the direction of observation) of the shaft 4. The
single carrier 3 has a hub 5 with which there engage four radial arms 6' in the present example. Furthermore, the drawing illustrates carrier arms 7 of a further single carrier located directly behind the single carrier 3 considered in the direction of observation, which further single carrier belongs to the front (considered in the direction of observation) twin carrier. In the direction perpendicular to the plane of the drawing, so that it is of course invisible, the twin carrier arranged at the distant end of the shaft in turn comprises a second single carrier which is located in line with the single carrier equipped with the arms 7. Each two axially aligned single carriers of the two twin carriers form a carrier pair whose arms 6 and 7 respectively, in each case commonly carry a supporting roller 8 or 9 as the case may be, in freely rotatable fashion. The supporting rollers 8, 9 of the two mutually staggered pairs of carriers, in each case form a supporting arrangement for articles 10 which are to be packed. If the conveyor drum has a four-arm design, then correspondingly, the machine has four supporting arrangements at the conveyor periphery. The supporting rollers, in each case rotatable about spindles 11 or 12 parallel to the axis of rotation 2 of the conveyor 1, will conveniently extend over the width of the conveyor 1 in the direction perpendicular to the plane of the drawing. The supporting arrangements constituted in each case by a pair of supporting rollers 8, 9, are uniformly distributed around the periphery of the conveyor and retain this uniform distribution even where, for purposes of adaptation to articles being wrapped, the spindle intervals of the roller pairs 8, 9 in the peripheral direction, are changed by altering the angle of ofiset. The reference 13 indicates a locking device which secured the mutual offset of pairs of carriers, after the adjustment has been made. The drive is provided by an electric motor 14 which, through a gearing arrangement 15, drives a main shaft 16 coupled with the conveyor 1.
When the conveyor 1 is driven, it carries out a circulatory movement as indicated by the arrow 17 and moves the supporting arrangements constituted by the pairs 8 and 9 of supporting rollers, along a predetermined and in this case circular locus. Along part of this locus, the conveyor 1 is assigned a fixed abutment arrangement 18 which, in accordance with the form of the locus, has the form of part of a circle viewed in side elevation. In the example illustrated, the abutment arrangement 18 is constituted by a part-cylindrical shell the face 19 of which faces the conveyor 1 and can be lined with a foam rubber liner or the like. The closed cooperating surface 19, extending substantially over the width of the conveyor 1, can, in modification of the example illustrated in the drawing, also be made up of sectional surfaces if, for example, the abutment arrangement 18 is given the form of a grid or the like made up of individual elements, strips and so on located one behind the other and in line in a direction perpendicular to the plane of the drawing.
At the front or top end, considered in the direction of rotation 17 of the conveyor 1, there adjoins the abutment arrangement 18 an entry track 20 inclined downwards towards said abutment arrangement 18, over which track the articles 10 to be wrapped roll down under their own weight to the conveyor 1. The feeding of the conveyor 1 with articles 10, is controlled by means of a distributor device 21 which extends at an interval transversely across the end of the entry track 20 and carries out a rotational movement in the direction of the arrow 22. In the example illustrated, the distributor device 21 consists of a rotating member carrying axial drive or detent fingers 23, and this, when rotated in the direction of the arrow 22, feeds articles 10 successively and at appropriate intervals to the conveyor 1. The drive movement to the distributor device 21 is adapted to the movement of the conveyor 1 in such fashion that in each case an article 10 is supplied to the conveyor when one of the latters supporting arrangements, constituted by the pairs of rollers 8, 9, is located in the receiving position before the end of the entry track 20. For transmission of the drive, a belt or chain-drive arrangement 24 is provided here, with a drive wheel 25 mounted on the main shaft 16, a
chain 26 and a drive wheel 27 which is carried upon a shaft 28 for the distributor device 21.
The machine furthermore comprises a supply reel 31 rotatable about an axle 29 in the direction of the arrow 30, from which the packing material is drawn off in the form of an endless web 32.
In order to prepare the subsequent automatic wrapping operation, first of all the web of material 32 is drawn over a supporting arrangement constituted by a roller pair 8 and 9, and an article 10 for wrapping supplied to this supporting arrangement, said article trapping the web 32 of material between itself and the corresponding supporting arrangement, in order to entrain the web with it when the conveyor 1 rotates in the direction 17. If the rotational movement of the conveyor 1 is now initiated, then the supporting arrangement which is carrying an article 10 for wrapping, describes a circular movement and passes into the field of action of the abutment arrangement 18. This abutment arrangement 18, coming into engagement with the article 10 being wrapped, causes the latter to describe a rotational movement in the direction of the arrow 33, the article hitherto simply having rested on the supporting arrangement and carried out a translatory movement corresponding to the movement of the conveyor 1. Through this rotational movement 33, in which the article 10 being wrapped is in engagement with the web of material 32, the article entrains the web 32 and wraps same tightly around itself. Sets of air-blast nozzles 34 are assigned to the machine in such fashion that they blow the front end 35 of the web into contact with the article 10 during the rotational movement, in order to lay it down smoothly and in uncreased fashion at the start of the rotational movement of the article. During the further course of the translatory movement of the conveyor 1 in the direction 17 the rotational movement of the article 10 as a consequence of its engagement with the abutment arrangement 18, continues until finally, at the end of the phase of engagement with said abutment 18, the rotational drive to the article l0 ceases.
The web of material 32 can, depending upon the nature of the packing, consist of paper, thermoplastic synthetic foil, viscose foil, composite material, e.g. paper bonded to synthetic material or the like. Insofar as complete packaging of an article 10 is required, the web 32 of material conveniently exhibits in a direction perpendicular to the plane of the drawing, a larger width than the corresponding dimension of an article being packed. When using paper as the packing material, for example, the projecting ends can be folded during the rotational phase, by providing fixed folding fingers (not shown in any detail), and laid against the ends of the article 10 being wrapped. When for example using shrinkable thermoplastic foils, in the course of an ensuing shrinking operation carried out by the application of heat, the foil automatically wraps itself around the ends of the article being packed.
In the example shown in FIG. 1, because of the relatively long period of engagement between the article being packed, and the abutment arrangement 18, said article carries out several complete revolutions. In so doing, the article 10 draws off a length of the web 32 of material which corresponds to its own circumference and the number of revolutions it executes, and thus wraps itself in said material. In order to dimension the length of the material which is drawn off, in the case of the machine shown by way of example in FIG. 1, each supporting arrangement is assigned a transverse cutting or shearing device which, in the example shown, consists of pivoting levers 36 each of which is pivotally mounted on one of the arms 6 of the single carriers 3 of a pair. The levers 36 are connected with one another by a cutter wire 37, the wire 37 extending parallel to the axis 2 of the conveyor 1. When using thermoplastic synthetic materials, the cutter wire 37 will conveniently be heated and part off a section of the web by melting it through. It goes without saying, of course, that instead of the cutter or shearing arrangement illustrated, and depending upon the kind of material involved, suitable other cutting or shearing arrangements can be used. The transverse cutter arrangements 36, 37 assigned to each supporting arrangement, are arranged on the conveyor 1 at that side of the belt 24 which is remote from the abutment arrangement 18, and, by means of a cam control arrangement which has not been shown in any detail, or some other positive control means, execute an outwardly directed parting-0E movement. In the example illustrated, this kind of positive control can be dispensed with and the parting-off movement can take place under the influence of the weight of the levers 36 themselves.
FIG. 1 illustrates the sequence of the wrapping operations during continuous operation of the machine. The article to be wrapped, which is in engagement with the as yet uncut web of material and the abutment arrangement, carries outa rotational movement on its supporting arrangement, such that it wraps itself in the web 32 of material, drawing this off from the supply reel3l at the same time. This rotational movement in engagement with the web 32, must, in order to be able to form an overlap in the packing, this being the case where complete packaging is involved, be more than 360. Accordingly, the time at which that part of the web of material which is in engagement with the article being wrapped, is parted off, must be so determined that parting-off only takes place after the execution of a rotational movement of more than 360, e.g. 400". If particularly thin material is being used for the wrapping, then it is also possible so to control the parting-ofi' operation that the article being packed is for example wrapped twice, completely, in the material, If, on the other hand, the web of material consists of a cohesive sequence of labels, then parting off can take placeat the time at which the article being wrapped has simply carried out a 180 revolution. As soon as the parting-off operation takes place, through the agency of the transverse cutter device 36, 37, the tension in the web of material, produced by the rotating article, ceases. In order to ensure that at this instant material does not cease to be pulled from the supply reel 31, the time of partingoff is so contrived that at this time or at any rate immediately after this time, a further article 10 is in position upon a succeeding supporting arrangement (considered in the direction of rotation) and has in turn come into engagement with the web of material 32 and entrained same with the continued movement of the conveyor 1 in the direction of the arrow 17. While, in respect of this additional article, a wrapping operation of the kind already described is continuing, the article 10 previously in engagement with the web of material 32, because of its contact with the abutment arrangement 18 continues its rotational movement so that the now parted section of the web is completely wrapped around the article. A further set of nozzles 38 reinforces the application of the trailing end 39 of the web section to the article. In order to fix the section of the material web to the article being wrapped, a number of possibilities are open which depend upon the nature of the material involved. If the material is of the hot-sealing kind, then during the remainder of the rotational movement of a fully wrapped article, a sealing operation can be carried out, for example by means of welding jaws arranged in the abutment 18 in the terminal portion thereof. If the material involved is simply a sticky one, then it is possible, preferably prior to the parting off of a section, to provide the web of material on that of its surfaces facing the article being wrapped and either over the whole area or only over local areas, with an adhesive and for this purpose a suitable applicator device can be provided although this has not been shown in the drawing purely for reasons of simplicity. In the latter case, an adhesive application takes placesimultaneously with the wrapping operation.
At the end of the partial locus of movement of the conveyor 1, within which there is engagement between the articles 10 being packed and the abutment arrangement 18, the packed articles are conveyed, for example, over a dispatch track 40 to a collecting station, a further conveyor or other devices. In the case of shrinkable foils, the wrapped articles, in order to complete the packing process, additionally pass through a hot zone where, under the effect of the heat, the material is shrunk around the article.
The air-blast nozzles 34, 38 are supplied from a compressed air source indicated by the arrow 41, the supply being controlled as a function of the rotational movement of the conveyor 1. To this end, valves 44, 45 operated by earns 42, 43 are provided.
The cams are carried upon a camshaft 46 the drive to which is derived from the main shaft through a belt or chain drive arrangement 47.
The articles being wrapped can be constituted substantially by any cylindrical articles, e.g. boxes, glasses, rolls of wallpaper and the like. However, it is not essential that the articles being wrapped should have a cylindrical form over the whole of their length, this irrespectively of whether it is a single packaging operation which is involved or the packaging of several articles together to form a multiple pack. It is sufi'rcient if the article has at least two substantially cylindrical zones located at an interval from one another in the axial direction, to enable contact location to take place. In this context, one can point as example to bottles which taper into a neck portion, various kinds of toys, and so on. The only critical factor where the shape of the articles being wrapped is concerned, is that overall they should have approximately cylindrical contact surface which will enable them to rotate on a supporting arrangement in co-operation with a fixed abutment arrangement.
FIG. 2 depicts a machine design which is substantially the same in its principle of operation, to that of FIG. 1. The modified construction, however, means that there is much greater versatility in terms of the application of the machine. Instead of a drum-type conveyor 1, the design shown in FIG. 2 employs a chain, web, belt or similar kind of conveyor 48, the endless conveyor elements of which are conducted around drive and return rollers 49, 50, 51. The movement of the guide arrangements is indicated by the arrow 52. The conveyor elements of the conveyor 48, which are located parallel with one another and at an interval behind one another in the direction perpendicular to the plane of the drawing, commonly carry freely rotatable mounted supporting rollers 8, 9 extending transversely across the width of the conveyor, of which in each case a roller pair 8, 9 forms a supporting arrangement for an article being wrapped. The supporting arrangements constituted by the rollers 8, 9 are distributed over the length of the conveyor 48 at uniform intervals. The manner in which the supporting rollers 8, 9 are supported by and mounted on the conveyor elements of the conveyor, is so contrived that the mutual interval between the axes of a roller pair forming a supporting arrangement, can be varied.
The axles of the return and drive rollers 49, 50, 51 as well as the spindles of the supporting rollers 8, 9 extend in this example in the horizontal direction in all cases.
In order to feed the conveyor 48, a feeder mechanism is provided consisting of an incline track 53 upon which the wrapped articles 10 tend to roll down under their own weight. An escapement device 54 regulates the distribution of articles 10 to the supporting arrangements 8, 9 of the conveyor 48. The operation of the escapement device 54, with its detent fingers 55, is effected as a function of the drive to the conveyor 48. The supply reel 31 assigned to the conveyor 48, rotates freely about a fixed axle 29, in the direction of the arrow 30. The web of material drawn from the reel 31, is once again marked 32 and in the zone in which the conveyor 48 is fed with articles for Wrapping, passes over the supporting arrangements in the manner described in principle hereinbefore.
In a further modification of the system, the conveyor 48 is assigned a group of lengthwise strips, bars 56 or the like, to do duty as abutment arrangements, these being pivotable about a fulcrum in a free fashion at 57, and forming a substantially comb shaped abutment arrangement which can execute a pivoting movement in the direction of the arrow 58. The group of bars 56 is followed by a further group of bars 59 which are pivotally mounted at 59 and can deflect in the direction of the arrow 60. The abutment unit formed by the lengthwise bars 56, is limited in terms of the deflection which it can execute, as also is the unit formed by the bars 59, by stops which have not been shown. The attitude of the bars 56 and 59 to the particular direction of the locus of movement of the conveyor 48, is not exactly parallel. Whereas the bars 56 converge slightly towards the path of movement considered the direction of movement 52, the bars 59 diverge slightly away from the path of movement, in their zone of operation.
The articles 10 consecutively introduced onto a supporting arrangement, first of all simply execute a translatory movement in the direction 52'followed by the conveyor 48, before, substantially, level with the deflection roller 50, they come into engagement with the abutment unit 56. The lengthwise bars 56, which are mounted so that they can pivot and deflect, automatically adapt to the dimensions of the articles being wrapped and rest upon them, causing them, because of the frictional contact, to rotate in the direction indicated by the arrows 61. Until the time of parting off, which is carried out by a transverse cutter device 62, the article 10 being wrapped, now caused to rotate by its contact with the abutment unit 56, entrains the web 32 of material and wraps itself in same. Accordingly, the ensuing articles 10, already supplied against the direction of movement 52 to the supporting arrangements, are imparted a rotational movement because of the pulling of the web of material 32 from the supply reel, the material passing beneath said ensuing articles of course, although at this stage said articles cannot wrap themselves in the web.
The parting off of a section of the web is effected by the single transverse cutting device 62, common to all the supporting arrangements, which, as a function of the drive to the conveyor 48, performs a rotational movement in the direction of the arrow 63. The cutting or parting-ofi elements once again take the form of cutter wires 29 in the transverse cutter device 62, these wires being located at diametrically opposite positions considered in relation to the axis 64 of rotation, on twin levers. Sets of air-blast nozzles corresponding to those used in the machine of FIG. 1, are again marked 34 and 38. As far as the execution of the actual packing operation is concerned, in order to avoid unnecessary repetition, attention is drawn to the earlier descriptions. After coming into engagement with the abutment unit 56, the articles being packed pass during the wrapping phase into engagement with the abutment unit 59 and continue their rotational movement after completion of the parting-off operation, in order to completely wrap around themselves the remainder of the section of the web of material. The continued rotational movement at the same time ensures that even after the completion of the actual wrapping phase, the material cannot unwrap itself from a packed article again. Fixing in position of the packing material on the article being packed, is effected in this kind of machine too, in the before described manner by sticking or hot type of sealing.
In the example shown in FIG. 2, the conveyor 48 is followed by a conveyor 65 which receives the packed articles 10, said conveyor 65 likewise being provided with supporting rollers 66 which act in pairs to provide a support for the articles 10. At an interval above the load-bearing run of the conveyor 65, which runs in the direction 67, an abutment arrangement 68 is provided with a co-operating surface 69 which is heated and has its temperature thermostatically controlled for hot-sealing purposes. This spring loaded and adjustable abutment arrangement 68 can, if material which can be hot-sealed is used, carry out sealing in the zone of overlap of the material surrounding the packed article and/or at the same time do duty as the heat treatment station for the shrinking operation if shrinkable foils have been used for wrapping. Using paper as packing material, this heat treatment can be employed to accelerate the hardening and drying of any adhesive which may have been used. The drive once again takes the form of a motor 14 with gearing arrangements 15.
The motor drives a shaft 70 for the conveyor 65, from which shaft the drive for the main shaft 16 of the conveyor 48 is derived by a chain drive system 71. Also taken from the main drive shaft 16, via a chain drive arrangement 72, is the drive for a shaft 67 for the transverse cutting device 62, and, via a chain drive arrangement 47 the drive for a camshaft 46. Valves for the air blast nozzles 34, 38 are once again marked 44, 45. On the camshaft 46, the cam 74 is fixed which, through a follower rod 75, operates the distributor device 54.
The machine shown by way of example in FIGS. 3a, b, once again comprises a chain conveyor 48, the conveyor elements or chains of which are carried in endless fashion around return (deflection) and drive wheels 76, 77. Again, they carry supporting rollers 8, 9, which are freely rotatable on spindles 78, 79, in each case a pair of such rollers forming a supporting arrangement for article 10 which is to be wrapped. The supporting arrangements are distributed at uniform intervals along the length of the conveyor. In the design shown in FIGS. 3a, b, the basic equipping of the conveyor provides for 12 supporting arrangements. Commencing from this basic equipment, the number of the supporting arrangements can be doubled or for that matter halved, for example, without otherwise modifying the conveyor 1, this as will be described at a later point. Depending upon the fundamental design of the conveyor, the number of the supporting arrangements in the basic equipment, can deviate from that shown in the illustration and can for example, be six, eight, 14 and so on. The arrow 52 illustrates the direction in which the chains of the conveyor run, these chains being formed as link chains 80, 81, 82, 83. In the example illustrated, the spindles 78 for the supporting rollers 8 (in each case located foremost in the direction of transit 52) of a supporting arrangement, are attached to the external chains 80, 83 through lugs 84, and the spindles 79 of the supporting rollers 9 (located to the rear considered in the direction of transit 52), are secured to the internal chains 81, 82 through lugs 85. In order to support the chains, supporting rails 86, 87, 88, 89, can be provided in the neighborhood of the load-bearing run.
In order to supply it with articles 10 for packing, the conveyor 48 is assigned a feed mechanism comprising an inclined entry track 53. The latter terminates in the region above the wheel 76. Above the end of the track 53, an escapement arrangement 91 which can move up and down in the direction of the arrows 90, is arranged. This escapement arrangement or distributor device 91, will for example be operated by means of a solenoid which has not been shown. The operation of the escapement 91 is linked to the movement of the conveyor 48. The example illustrated to this end exhibits a camshaft 46 the rotation of which is derived from the rotation of the wheel 76 of the conveyor, through a chain drive 92. On the camshaft 46, cam 93 is fixed, this having cam lobes, not shown in any detail, corresponding to supporting arrangements 8, 9. These cam lobes, through a circuit which has not been illustrated, control the excitation of the solenoid which operates the escapement 91.
Once again, the entry end of the conveyor 48 is assigned a supply wheel 31 for a web of packing material 32. The web of material 32 which can be drawn off the supply wheel 31, passes over an extractor device marked in toto by 94, this comprising freely rotatable guide rollers 95 and a drive roller 96 around which the web of material passes. The drive arrangement for the drive roller 96 is an electric motor 97 with a gearing system 98. After passing the extraction or withdrawal device 94, the web of material 32 passes over supporting arrangements 8, 9 in each case appearing beneath the entry track 53 ready for reception of an article 10 for packing, said supporting arrangements carrying the articles with the web of material 32 between said articles and themselves. In order to give the conveyor a continuous translatory movement, an electric motor 99 with a gearing system 100 is provided. The motors 97, 99 are assigned a common proportional controller 101 which adjusts the r.p.m. of the motor 97 in a predetermined proportion to the r.p.m. of the motor 99. The r.p.m. of the motor 99 here constitutes the command variable. The proportional controller 101 comprises a known or suitable other device 102 for setting and adjusting a set point value S for the control ratio between the r.p.m. of motor 97 and the r.p.m. of motor 99. Because the r.p.m. of motor 99 is proportional to the speed of circulation v, of the conveyor 48, and the r.p.m. of motor 97 proportional to the speed of withdrawal and transit, v of the web of material 32, the proportional controller 101 provides proportional control of the speed v of the web of material 32 in relation to the speed v of the conveyor 48. The set point value S provided to the proportional controller .101 is accordingly a quantity which is proportional to the particular desired speed difference V V V this speed difierence V requiring to have a value equal to or greater than 0. During operation of the machine, the set point value S can have a constant magnitude. By means of the device 102, however, the set point S can also be periodically varied during operation of the machine, so that the motion of the conveyor is periodically varied also. This deriving of a periodic variation in the motion can be obtained by means of a suitable cam operated system derived from the cam shaft 46. The elements of such a system will be entirely familiar to those skilled in the art.
The conveyor 48 is assigned a transverse cutter device 103 in the neighborhood of its entry end, which, in the example of FIG. 3a, comprises two hot-wire elements, 104 as the partingoff devices. The two hot-wire elements or filaments 104 are attached to carrier brackets 105 and arranged diametrically opposite one another vis-a-vis a common axis of rotation 106. The arrangement of the transverse cutter device 103 at the entry end of the conveyor 48 is so contrived that cutting operations in all cases take place at a specific position, and indeed in the region between a supporting arrangement located above the deflection wheel 76 and in front of same considered in the direction of transit 52. The rotational movement of the rotating transverse cutter device 103 is derived in the present example from the rotational movement of the deflection wheel 76 through a chain drive 107, and is thus adapted to the movement of the conveyor. Instead of a rotating hot-wire transverse cutter, it is equally possible to use any other suitable transverse cutter device, with a drive arrangement which is adapted to the movement of the conveyor. This will in particular be necessary where the web of material is not made of a thermoplastic foil or of hot-sealing viscose foil, but of paper, composite material or similar materials.
In the neighborhood of the transverse cutter device 103, there is also provided air-blast device 108 consisting of one or more air-blast nozzles, by means of which, against the underside of what becomes the forward end 109 (FIG. 6) of the web 32 of material, after the parting-off operation, an airflow 110 can be directed, which airflow lifts said forward end of the web of material and applies it against the front side (considered in the direction of transit) of an article moving along on its supporting arrangement. Above the cutting zone, it is furthermore possible to provide a suction device 111 by means of which the vapors produced during the hot-wire parting-off operation, can be drawn away and at the same time an upward airflow 112 produced which, in turn, tends to lift the forward end 109 of the web of material and apply it against the front side of an article 10 which is being wrapped. The supply of air to the air-blast device 108 and the operation of the suction device 111, can be controlled by cams 113 and 114 and valves 1 15, 116 operated thereby, the cams being mounted on the camshaft 46 so that the air-blast and suction arrangements are operative only intermittently, that is to say during the parting-off operation and for a certain interval thereafter.
In the direction of transit 52, the transverse cutter device 103 is assigned an abutment device 117 for producing a rotary wrapping movement in the articles 10 which are to be packed and which are resting upon the supporting arrangements 8, 9. In the example illustrated, this abutment device 117 consists of two lengthwise bars with a chamfered entry zone 118 at their forward ends, the top sides of which, 119, when supporting arrangements pass in the course of movement of the conveyor, come into engagement with the supporting rollers 8, 9
as shown particularly clearly in FIG. 5. Because of this engagement between the supporting rollers 8, 9 and the top sides 119 of the abutment bars or rails 117, supporting rollers are made to rotate in the direction of the arrow 120 and in turn produce rotation of the article 10 carried by a pair of rollers 8, 9, this in the direction of the arrow 121, with the consequence that the particular article being packed automatically wraps itself in the relevant section 32 of the web 24 packing material. Substantially simultaneously with this, or for that matter following this phase, the rotary wrapping movement to be initiated can also be derived from a further abutment arrangement 56. This abutment arrangement 56 is once again formed as a weighted plate, which is located above the load-bearing runner of the conveyor and can possibly be heated by resistance heating elements 122. The adjustment of the interval between the abutment plate 56 and the load-bearing runner of the conveyor can for example be effected by means of an adjuster spindle 123, while springs 124 control the weighting of the supporting arrangement. In the case where the web of material is constituted by thermoplastic foil or viscose foil which can be hotsealed, the heated abutment plate 56 serves to fix in position the section of the material web which now tightly envelopes the packed articles.
The packing operation evolves in the following manner: FIGS. 3a and 3b illustrate a stage in which a transverse cutter element 104 has just parted off a section 32' from the web 32 of material which was hitherto a cohesive whole. At this instant, a supporting arrangement 8, 9 is located in the receiving position beneath the entry track 53 of the feed mechanism, and has just received an article for packing from said mechanism. The web of material 32 extends over said supporting arrangement and its forward end 109 extends up to the point at which the section 32 has been parted off. The article 10 for packing, fed from the feed mechanism onto the supporting arrangement located below it, rests upon the web 32 of material and, through this, upon the supporting rails 8, 9. The parted off web section 32 has a length which exceeds the wrapped circumference of the article 10 being packed, by for example 20 percent. This length of the web section 32, is determined on the basis of the mutual intervals of the supporting arrangements as a whole, in association with the mutual intervals between the supporting rollers 8 and 9, provided, and this is the assumption initially made in the following, that the predetermined set point value S is zero and thus the speed of withdrawal and supply v of the web of material 32, is equal to the speed v, of the conveyor in the transit direction 52. In the course of the continuous movement of the conveyor, the airflows 110, 112 lift the forward end 109 of the web of material and apply it against the article to be packed, which is moving forward on its supporting arrangements, this as shown in detail in FIG. 6. The article for wrapping, just fed onto a supporting arrangement, moves with said arrangement in the transit direction 52, synchronously with the web of material 32 which latter, as hereinbefore defined, is withdrawn from the supply reel 31 and supplied to the conveyor by the extractor device 94, at a speed v which is the same as the speed of forward movement v In the course of this forward movement accordingly the article 10 being packed initially executes no rotational movement of its own on its supporting arrangements. Shortly before the article 10' reaches a position shown in FIG. 3a, the above-described parting-off operation takes place, by means of which the section of the web of material which is assigned for the packaging of the article 10' is cut off. This article 10 now in engagement with its section 32 of the web of material, passes in the course of the further forward movement of the conveyor, into that region in which the supporting rollers 8, 9 of its supporting arrangement, come successively into engagement with the abutment rails or bars 117. Because of this contact, the supporting rollers 8, 9 are made to rotate in the direction of the arrow 120 and in turn, through the medium of section 32 of the web of material, make the article 10' rotate and perform a wrapping movement in the direction of the arrow 12].
Following this stage, the article being wrapped, now wrapped in the appropriate section of the web of material, comes into engagement with the abutment plate 56 which, possibly by the application of heat, carries out the securing of the wrapping material to the article. The time at which a rotational wrapping movement is derived from the abutment rails 117, and the time for which this kind of rotary wrapping operation lasts (i.e. the time elapsing up to the arrival of the article at the other abutment plate 56), can be modified by adjusting the abutment rails 117, in the direction of the arrows 125. Depending upon the nature of the material used, it is possible either to exclusively use the abutment plate 56, or exclusively the abutment rails 117, in order to transfer a rotary wrapping motion to the articles being packed.
If articles are to be wrapped which have small diameters, and correspondingly require sections of web material of only short length in order to wrap them, then the proportional controller 101 can be supplied with a setpoint value S which is greater than zero, so that the extractor device 94 pulls off the web of material 32 at a withdrawal and feed rate v which is slower than the conveyor speed v In this fashion, a supporting arrangement supplied with an article for wrapping from the feed mechanism and moving forward with said article in the transit direction 52, will lead the web of material 32 extending between this supporting arrangement and the article, with the consequence that while the point at which the cutting or parting-off operation is carried out remains unchanged, the corresponding cut section of web will be shorter. The length difference DL obeys the equation DL (v v t, where t is the time elapsing between two successive cutting or partingoff operations. The length difference is thusproponional to the speed differential Vbetween the speeds v and v From the foregoing, it will be evident that by effecting proportional control between the speeds v and v the length setpoint for web sections 32', can be modified to adapt it to varying dimensions of the articles being wrapped. The design of the machine, i.e. the basic equipping of the conveyor with supporting arrangements, the intervals between the supporting arrangements and between the supporting rollers of such an arrangement, is efiected on the basis that the wrapping of articles of the maximum possible size is carried out at a differential speed of V= 0.
If we consider the time interval t elapsing between two successive cutting operations, as being the fundamental operating cycle time of the machine, then the setpoint value S which determines the speed differential V, i.e. the setpoint value of the proportional controller 101, can remain constant during an operating cycle. However, it is also possible to modify the setpoint value S during such an operating cycle in order, for example, to modify the differential speed Vduring the time interval t. It is conceivable, in other words, that by corresponding modification of the setpoint value produced, during an operating cycle, the speed v of the web of material could be set to zero for a specific time 2 (shorter than the time t), while the speed v during the remainder of the time interval t t,, is set to the value v,. In this fashion, a differential movement between the web of material 24 and the supporting arrangement over which it passes, can be limited to a fraction of the cycle time I. By corresponding delay between a cutting or parting-off operation, and the supply of an article for wrapping, to a supporting arrangement, it is possible to limit the differential movement between the supporting arrangement and the material web 32 passing over same, to the time interval elapsing between the cutting operation and the supply of an article for wrapping. Accordingly, independent rotational movement of the article being packed, during its translatory motion, can be inhibited until the time at which its proper wrapping rotational movement should commence.
As FIGS. 7 to 9 illustrate in more detail, there are additional possibilities of variation in order to adapt the machine to differing conditions of operation, in particular to differing diameters on the part of articles being packed.
FIG. 7 provides a fragmentary illustration of the machine of FIG. 3a, in the context of its use for the packing of articles 200 which have half the diameter of the articles 10 of FIG. 3a. If we assume that in the machine of FIG. 3a, 3b, the packing of the articles 10 is carried out at a differential speed V= 0, then the packing of the articles 200 will be carried out at a differential speed V which is obtained from the equation V= v v where v v and V= v,. For the rest, all that is necessary is to adapt the mutual spindle intervals of the supporting rollers 8, 9 of the supporting arrangements, to the reduced diameter of the articles 200 being packed.
FIG. 8 illustrates a machine design similar to that of FIG. 3a, in which the conveyor 48 is equipped with six supporting arrangements. Once again, articles 10 are being wrapped which have a diameter corresponding to the diameter of the articles shown in FIG. 3a and 3b. Instead of the rpm. ratio selected in the case of FIGS. 3a and 3b, between the speeds of the wheel 76 and the camshaft 46, namely the ratio 2:1, this ratio has been set to 1:1 by the use of a correspondingly enlarged chainwheel 126. The transverse cutter device 127 simply comprises a single part-off element 104, the relationship of the drive to this device, and the translatory movement of the conveyor 48 remaining otherwise unchanged. In addition, the transverse cutter device 127 has been offset somewhat to the right, in the drawing. The differential speed V v, v once again amounts to A v,.
FIG. 9 illustrates a machine design similar to that of FIG. 8, with six supporting arrangements for wrapping articles 300 having a diameter which is twice that of the diameter of the articles 10. The differential speed V is zero. Corresponding with the design of FIG. 8, in the design of FIG. 9 too, the cutter device 127 simply possesses one parting-off element 104. The distance between the transverse cutter device 127 and the wheel 76 corresponds, however, to the interval shown in FIG. 7 and also for that matter in FIG. 3a. The speed ratio between the wheel 76 and the camshaft 46, is 1:1, as in the case of FIG. 8. For the rest, it is only the interval between the supporting rollers 8, 9 which has been correspondingly enlarged to accord with the diameter of the articles 300.
As the foregoing examples show, relatively minor modifications to the machine will suffice to take account of arbitrary operating conditions. It is entirely obvious that, for example, the machine could also be equipped with 18 supporting arrangements etc., if modified in this same manner.
The invention is in no way limited to the examples hereinbefore described. Within the scope of the invention, numerous modifications in order to adapt to the nature and dimensions of articles being wrapped, and in order also to adapt to the nature and properties of packing materials, can be introduced. For example, it is possible, to support the abutment arrangement or arrangements in spring-loaded fashion, and also to spring-load these abutment arrangements vis-a-vis the conveyor. If the conveyor is adequately wide and the supporting arrangements likewise, then if several individual articles are supported at intervals one behind the other on a supporting arrangement, they can simultaneously and individually be wrapped in one operating cycle. In this context, in order to split up the web of material into a corresponding number of longitudinal strips, a suitable lengthwise cutter apparatus can be provided. Also, it is conceivable that preheating of the web of material could be introduced in particular when using materials of substantial thickness, this in order to improve the flexibility of the material. Yet again, it is possible to heat the supporting rollers of the supporting arrangements.
1. In a method of completely or partially wrapping an article or a plurality of articles presenting at least partly a substantially cylindrical surface with sheet material to package or label same, using in particular thermoplastic foils, viscose foil which can be hot-sealed, paper, composite materials or the like, comprising the steps of withdrawing the sheet material in the form of a web from a supply reel and guiding it to the article to be wrapped,
setting the article into rotation while it engages the sheet material, so that the article entrains the sheet material and wraps it around its external periphery, and while it is in said engagement imparting a translational movement to said article along a predetermined path directed transversely of the axis of rotation of the article,
the improvement comprising the steps of successively releasing articles so that they are successively placed onto predetermined areas of said web, and move forward in engagement with the web after having been released by releasing means,
engaging abutment means which act on the outer periphery of each article in a direction opposite to the translational movement thereof thereby imparting on each article a rotational motion and causes the article to wrap the web around its outer periphery, and
severing a predetermined portion of the web after the article has been placed on the sheet material.
2. A method as claimed in claim 1 further comprising parting off the web after the article is brought in engagement with the web but before rotational movement is imparted to the article, the web being cut to leave a web section of predetermined length corresponding to the dimension of the article.
3. A method as claimed in claim 1 further comprising imparting feeding movement to the web to feed it from its supply reel at a speed which is the same as or less than the speed of translational movement of a supporting arrangement which causes said translational movement.
4. A method as claimed in claim 1 further comprising maintaining the article in rotation during a further translatory movement after it is wrapped by the sheet material, until it reaches a dispatch position.
5. A method as claimed in claim 1 further comprising coating the surface of the sheet material which faces the article being packed, prior to or during rotation of the article being packed, with a coating of adhesive either over localized areas of the sheet material or over the whole or its area.
6. A method as claimed in claim 1 further comprising exposing the wrapped article to heat for the purpose of hot-sealing,
shrinking or drying the sheet material enwrapping it.
7. A machine comprising in combination,
a supply reel rotatably mounted in said machine for unreeling a web of sheet material,
supporting means for articles to be at least partially wrapped with said sheet material, said supporting means comprising endless transport means operatively mounted thereon and moving said articles along a predetermined path,
means for guiding said web onto said endless transport means operatively connected to said supply reel, means for feeding articles at predetermined intervals onto said web at a location at which it has already been guided onto said transport means, the movement of said feeding being synchronized to the movement of said transport means, transverse cutting means operatively coacting with said transport means for severing a predetermined portion of said web after an article has been placed thereon,
abutment means operatively mounted along said predetermined path, said articles successively peripherally tangentially engaging the abutment means which acts in the direction opposite the movement of the transport means thereby causing them to be successively rotated by the frictional engagement therebetween and wrapping a predetermined portion of said web around themselves, said transverse cutting means severing said web upstream from said peripheral tangential engagement of said abutment means with respect to the direction of said articles along said prederimined path.
8. A machine as claimed in claim 7 wherein the transport means is an endless conveyor comprised of chains, belts or similar conveyor elements guided around deflection (return) and drive rollers, and the conveyor carries a plurality of said support elements distributed over its length.
9. A machine as claimed in claim 8 wherein the conveyor takes the form of a driven rotating drum with supporting elements for articles to be packed, which elements are distributed around its periphery.
10. A machine as claimed in claim 7 wherein a web extractor device is provided with at least one drive roller to rotate in engagement with the web of sheet material, by means of which the rate of withdrawal and supply of the web of sheet material can be set and regulated.
11. A machine as claimed in claim 10 wherein the drive movement for the drive roller of the web extractor device is derived from the drive system for the transport means, via a gearing system whose transmission ratio can be varied in stepped or in infinitely variable fashion.
12. A machine as claimed in claim 10 wherein the web extractor device and the transport means each have separate drive arrangements, and both drive arrangements are allocated a common proportional controller.
13. A machine as claimed in claim 12 wherein the proportional controller is provided with a device for adjusting the setpoint value.
14. A machine as claimed in claim 8 wherein said supporting elements are arranged at uniform intervals along the conveyor and supported thereon.
15. A machine as claimed in claim 8 wherein to do duty as said supporting elements, in each case pairs of supporting rollers or the like which together support an article for packing and are freely rotatable about parallel spindles, are provided, and these extend over at least part of the width of the conveyor.
16. A machine as claimed in claim 15 wherein the mutual center to center distance of the supporting rollers is adjustable.
17. A machine as claimed in claim 7 wherein the transport means takes the form of a driven rotating drum with supporting rollers for articles to be packed, which arrangements are distributed around its periphery, the mutual center to center distance of the supporting rollers is adjustable, and the rotating drum comprises two co-axially located twin carriers each located at one end and consisting of two single carriers on a common carrier shaft and in each case two single carriers of the two twin carriers are arranged in line with one another in the axial direction and together form a carrier pair supporting one of the rollers of a roller pair and both pairs of single carriers are adjustable in relation to one another in the angular sense in the peripheral direction.
18. A machine as claimed in claim 7 wherein the abutment means forms a co-hesive co-operating surface or one which is split up into subsidiary surfaces, and extends at an interval from the path of movement of the articles on the transport means, along said path and substantially parallel thereto.
19. A machine as claimed in claim 18 wherein the abutment means consists of a plate or the like extending substantially over the width of the transport means.
20. A machine as claimed in claim 18 wherein the abutment means consists of one or more lengthwise bars, strips or the like combined together to form a group.
21. A machine as claimed in claim 20 wherein the abutment means comprises several groups of straight lengthwise bars arranged one behind the other in the direction of movement of the transport means, these bars forming substantially comblike abutment units in which the attitude of the bars is in each case separately adapted to the locus of movement of the transport means.
22. A machine as claimed in claim 20 wherein the abutment bar or bars is or are pivotally mounted about a transverse axis in the neighborhood of its or their front end (considered in the direction of movement of the transport means), so that they can deflect through a range which is limited by stops.
23. A machine as claimed in claim 15 wherein the abutment means takes the form of at least one rail extending along the path of movement of the transport means over at least part of the length of said path, which bar sets the supporting rollers into rotation when the latter pass it.
24. A machine as claimed in claim 8 wherein the transverse cutting means is allocated to the transport means so as to lie at the side of the web of sheet material which is remote from the abutment means, and exhibits parting-off elements adapted to execute a parting-off movement which penetrates at one side between two successive supporting elements.
25. A machine as claimed in claim 24 wherein the conveyor is assigned a transverse cutter device which carries out all the parting-off operations and whose drive system is adapted to the drive system of the conveyor.
26. A machine as claimed in claim 24 wherein the transverse cutter means is arranged for adjustment along the path of movement of the conveyor.
27. A machine as claimed in claim 24 wherein each supporting element is assigned a separate transverse cutting device supported on the conveyor.
28. A machine as claimed in claim 8 wherein sets of air-blast nozzles are provided which are arranged to blow a stream of air onto the end of each section of sheet material formed by the severing operation, and hold same into contact with the article being wrapped.
29. A machine as claimed in claim 8 wherein the conveyor is assigned a feed mechanism located at a position in front of the abutment means considered in the direction of movement of the conveyor.
30. A machine as claimed in claim 29 wherein the feed mechanism comprises a distributor device adapted to the con veyor drive system and supplying articles for packing successively, at intervals, to the supporting elements on the conveyor.
31. A machine as claimed in claim 29 wherein the feed mechanism exhibits an inclined entry track at the end of which, adjacent the conveyor and terminating above the conveyor, is located an escapement device capable of intermittently opening and closing.