US3218776A

US3218776A - Packaging method and apparatus

Info

Publication number: US3218776A
Application number: US137131A
Authority: US
Inventors: Charles E Cloud
Original assignee: Cloud Machine Corp
Current assignee: Cloud Machine Corp
Priority date: 1961-09-11
Filing date: 1961-09-11
Publication date: 1965-11-23
Anticipated expiration: 1982-11-23
Also published as: GB1019005A; GB1019006A; DE1411993A1; DE1287502B

Description

Nov. 23, 1965 c. E. CLOUD PACKAGING METHOD AND APPARATUS 2 Sheets-Sheet 1 Filed Sept. 11, 1961 Cfiar/ea 27 91 213 21 v BY M, M r, 8 Z W {w Nov. 23, 1965 c. E. CLOUD PACKAGING METHOD AND APPARATUS 2 Sheets-Sheet 2 Filed Sept. ll, 1961 L a 1. .J.-... J.

"J0 Lil y L s zm' f United States Patent 3,218,776 PACKAGING METHOD AND APPARATUS Charles E. Cloud, Wilmette, 111., assignor to Cloud Machine Corporation, Skokie, 111., a corporation of Delaware Filed Sept. 11, 1961, Ser. No. 137,131 21 Claims. (Cl. 5339) The present invention relates to stretch-wrapping and in some of its aspects is particularly useful in the packaging of a product.

Stretch-wrapping is an extremely economical and attractive form of packaging in which the package is formed of thermoplastic film which is either stretched about an article or, in the form here illustrated, stretched by suction into cavities to form pocket which are filled, and then covered with another film. Stretching the film into the cavities necessitates that the edges of the film be restrained against being drawn into the cavities and this has proven troublesome. Special devices have been provided to hold the edges of the film in the desired location beside the cavities as the packages are being formed. Such devices add to the complexity, cost and maintenance problems of the packaging machine. They are avoided by one aspect of the present invention.

Cost of packaging is extremely important in low priced products sold in huge quantities. Saving a fraction of a mill per package can provide a profit where otherwise there would be a loss.

Among the factors to be considered in the production of marketable packages is that the films from which the packages are formed must be securely affixed to each other so that the package is strong and tight. It should not break open or leak under the more severe ordinary handling to which it will be subjected. If several products are to be packaged in separate compartments as a single unit, the package must maintain the separation of the products, each in its own compartment.

My invention, both method and apparatus, is intended to provide a packaging machine that will satisfy the foregoing requirements and overcome the various problems encountered by prior art devices. It is comparatively simple and inexpensive yet has a high production rate. The finished packages are strong and neat in appearance. They are regularly shaped and evenly filled with a predetermined quantity of product. This latter factor is all the more significant when it is realized that no expensive complicated metering devices are employed to measure the product. A further feature of my invention is that a machine embodying it may be used one day for packaging given quantities of material. With relatively simple changes, it can go into production the next day packaging product of a greater or less quantity.

Further objects and advantages will become apparent from the following description taken in conjunction with the drawings.

Designation of figures FIGURE 1 is an elevational view of an embodiment of my invention in relatively diagrammatic form;

FIGURE 1A is a fragmentary diagrammatic view showing a modification;

FIGURE 2 is an isometric view of a package of product produced in accordance with my invention;

FIGURE 3 is an isometric view of a portion of the drum of FIGURE 1 illustrating the molds employed in the forming of the packages of product illustrated in FIGURE 2;

FIGURE 4 is a partial section through the outer portion of the drum and the filling hoppers further illustrating the structure of the molds and the filling thereof;

FIGURE 5 is an enlarged partial section of the drum and the apparatus for filling the film pockets with product;

FIGURE 6 is an enlarged elevational view, partially in section, of the apparatus for applying liquid to a surface of one of the films; and

FIGURE 7 is a plan view of the roller for loosening the packages of products from the molds.

Intent clause Although the following disclosure ofiered for public dissemination is detailed to ensure adequacy and aid understanding, this is not intended to prejudice that purpose of a patent which is to cover each new inventive concept therein no matter how it may later be disguised by variations in form or additions or further improvements. The claims at the end hereof are intended as the chief aid toward this purpose, as it is these that meet the requirement of pointing out the parts, improvements or combinations in which the inventive concepts are found.

General description In the packaging of this invention, as illustrated in the drawings, packages are formed from two ribbons of film, drawn respectively from

rolls

16 and 21. That from roll 16 is drawn around heated roll 17, which presses it into sealing engagement over cups or cavities 11, into which this film is drawn by suction to form pockets. Near the top of drum 10 the pockets are filled, and the fill is leveled off by wipers 5'7, 58 and 59 which also clean oil the exposed surfaces of the film surrounding the pockets. The second ribbon is made tacky by slight moistening by wick 64 and by mild heat from roll 23, and is sealed over the filled pockets to complete the packages.

The packages are then cut apart and dropped on delivery conveyor 35.

Pocket formation FIGURE 1 illustrates a drum generally 10 which has a plurality of cavities generally 11 into which into which one sheet of film is drawn to form pockets, each of which is to be filled with the product to be packaged. Drum 10 is rotated in the direction indicated by arrow 12 by a suitable power means. In FIGURE 1, the power means is illustrated diagrammatically by a gear head motor 13, the output shaft of which is connected to drum 10 by a chain or belt 14. I contemplate that the drum 10 rotates at a constant speed, but some users of my invention may prefer that it move a step at a time.

In my process, a ribbon of film from a roll 16 is laid over the periphery of drum 10, covering both the pockets 11, and the surface of the drum surrounding the pockets, which should be relatively smooth. In actual practice, this smooth surface is obtained by polishing the surface of the drum. A thermoplastic film is employed, with the film being heated to a plastic condition and immediately pressed onto the surfaces of the drum surrounding the pockets. In the illustrated embodiment, a heated metal roller 17 is employed to press the ribbon of film against the surfaces of the drum. The roller is heated to a temperature sufficient to render the film plastic by the time that it is pressed against the drum 10. The actual temperature, of course, will vary depending upon the film, its thickness, the length of time that it remains in contact with roller 17, etc. With the films that I have employed, drum 17 is heated to about 140, but it might be as low as about 100 or as high as about 300 F.

A vacuum is applied to the cavity to draw the film that covers the cavity opening into the cavity and define a pocket to receive the product to be packaged. This vacuum should be applied almost instantaneously after the cavity is completely covered with film. As a matter of fact, the vacuum actually might be applied to the cavity before it is covered with film, but obviously it will not be effective until the covering is complete so that a seal is obtained about the periphery of the cavity opening. Thus for practical purposes, even in that instance there would not be an effective application of vacuum until the instant of the covering of the cavity, and such a practice would be within my concept of applying a vacuum immediately following the covering of the cavity with the plastic film.

In the past it has been deemed necessary to restrain the side edges of the film to prevent displacement of the ribbon of film as pockets were formed therein to receive product. However, I have discovered that if the surface surrounding the cavity is made relatively smooth, e.g. polished, the film heated to plastic condition and pressed against those surfaces, and a vacuum applied to the cavity to draw the film into the cavity immediately upon the cavity being covered with film, such restraining devices for the ribbon of film are unnecessary. This greatly simplifies the apparatus to carry out the method and its operation.

Filling pockets The pocket thus formed in the film is then filled level full with product. To do this with a particulate product, a mound of product is formed in the pocket. This mound is higher than the top of the pocket although it will not necessarily fill all the space up to the sides of the pocket. This mound is formed when the pocket is adjacent the top of drum by a filling apparatus generally 18. Thereafter, the top of the mound is flattened to a level below the top of the pocket. At least a portion of excess material so displaced from the top of the mound is used to fill any voids about the sides of the pocket. Thereafter, the film surrounding the pocket is wiped and excess material is used to fill the pocket to the level of the top of the pocket. In the illustrated embodiment, these latter steps are performed by the leveling apparatus generally 19 of FIGURE 1.

The term particulate material is used herein to refer to material of a type wherein a number of units of the product are indiscriminately grouped together in a single package. The actual size of the particles may vary greatly from a very fine powder to particles that are substantially larger, yet sufficiently smaller than the size of the package that a number thereof may be included in a single package. For the purposes of illustration, one particulate material described in connection with the illustrated embodiment is a detergent. Another, illustrated packaged in companion packages is a bluing powder.

Closing packages The pocket is now ready to be covered with a second film from roll 21 and the two films sealed together. The film of roll 21 is a film which is liquid soluble. For example, it may be a polyvinyl alcohol film, which is soluble in water. In the usual practice of my invention, the film of roll 16 will be a film corresponding to that of roll 21. Before the two films are pressed together, sufficient of the liquid in which the film of roll 21 is soluble is applied to that film to render it tacky to obtain a secure bond between the two films. It is important that the amount of the liquid applied to the film to render it tacky be very accurately controlled. If too little liquid is applied, the required tackiness will not be obtained. If an excess of liquid is applied, the film will be weakened and possibly even destroyed. I have found that the amount of liquid can be very accurately controlled by moving the film from roll 21 along a generally vertical path, which in the illustrated embodiment is defined by rollers 22 and 23. While the film is moved along that path, the liquid is wicked onto the face of the film from a bath. By maintaining the surface of the bath at a given elevation with respect to the point of application (or a given distance between the point of application and the surface of the bath), the liquid actually applied to the surface of the film will be constant. The liquid-applying apparatus generally 24 is best illustrated in FIGURE 6.

After the film from roll 21 is rendered tacky by the wicking process, it is pressed over the pockets of product, with the two films in the areas surrounding the pockets being pressed together to obtain cohesion. In the illustrated embodiment, the two are pressed together by roller 23, which is resiliently urged toward drum 10 by spring 25, I find that an extremely secure bond between the two films is obtained by now applying heat. To achieve this, I heat roller 23, which conductively heats the top film from roll 21 and the bottom film from roll 16.

Thereafter, the sides of the joined ribbons of film are pushed inwardly to aid in loosening the pockets of packaged product from the cavities. This is done by angularly aligned roller 27 at one side of drum 10 (see FIGURES 1 and 7) and an oppositely aligned roller (not shown) at the opposite side of drum 10.

Severing of packages The film now is cut longitudinally and transversely to define each individual package of product. The longitu-- dinal cuts are made by a plurality of knives 28 having cutting edges extending into peripheral grooves 29 in drum 10. The ribbon is cut transversely by a pair of' knives 30 mounted for rotation on a rotating shaft 31.. Knives 30 have cutting edges 32. The rotation of shaft. 31 is timed so that the cutting edges 32 will extend intotransverse slots 33 about the periphery of drum 10. As. best seen in FIGURE 3, there is one of slots 33 at each side of a mold. The individual packages of product 34 are deposited on and carried away by a conveyor 35. The: separation of the packages 34 from the cavities within which they were formed can be facilitated by applying air under pressure to the cavities in the same manner in which vacuum was applied thereto in the formation of the pocketsformed in the making of the packages.

Drum construction The cavities 11 in drum 10 are defined by plastic inserts fastened in openings in the periphery of the drum. Since two types of products are to be packaged together, there are a plurality of large openings 37, adjacent each of which is one of the small openings 38. The large openings each receive a large cup-shaped plastic insert 39 while the small openings receive a small cup-shaped plastic insert 40. Each insert is affixed in its opening by a screw 41 and spaced from the bottom of its opening by a plurality of washers 42. More or fewer washers would vary the spacing of the insert from the bottom of the pocket,

and, hence, the depth of the pocket above the insert. The sides of the plastic insert are spaced slightly from the walls of the opening into which the insert is fitted, whereby a fluid communication is obtained about the sides of the insert.

A plurality of passageways 44 are used to draw a vacuum on the cavities. At one end, each passageway communicates with a cavity. At the other end, it opens at the axial opening through the drum, into which opening the shaft 45 on which the drum is journaled extends. A slot (not shown) extending through shaft 45 and partially 7 about its periphery in a circumferential direction is aligned to communicate with each of the passageways 44. This provides a valving arrangement for the drawing of a vacuum on the cavities. Vacuum is applied to the interior of pipe 45 by means not shown. One end of the slot is positioned so that each of passageways 44 will come into communication with the slot, and thus with the interior of pipe 45 at or slightly before each cavity reaches the position illustrated by cavity 11a in FIGURE 1. As previously explained herein, a vacuum should be applied immediately upon the cavity being covered by the film from roll 17. Thus the valving construction just described should be so constructed as to apply vacuum at this time. The exact point at which the passageway will reach the other end of the slot and thereby cut off the vacuum from the cavity is less important. In the apparatus I have devised, it will be after the two films have been aflixed together to form the package by roller 23. Thus the vacuum can be cut off at substantially any time after each cavity passes what would be about the 11 oclock position in FIGURE 1.

When the vacuum is applied to a cavity, the air is drawn out from below the film and down about the sides of the plastic insert. The softened film initially bows down in the center with the center first contacting the central portion of the plastic insert. Continued evacuation acts to draw the remainder of the film completely down into the cavity to form film pockets, as best illustrated in FIGURE 4.

The filling apparatus 18 comprises a pair of

hoppers

47 and 48. Hopper 47 is filled with one particulate material, e.g. detergent 49. Hopper 48 is filled with a second particulate material, e.g. bluing powder 50. The bottom plate 51 of hopper 47 has a plurality of openings 52 through which the detergent 49 flows to fill the large pockets as defined by the large openings 37. Hopper 43 has a bottom plate 53 with a plurality of openings 54 through which the bluing powder 50 flows into the small cavities defined by small openings 38. The particulate material flows into the pockets in a peripherally elongated mound which is of generally truncated triangular cross section as viewed transversely of the drum. The correct amount of material to properly fill the pockets is obtained by raising or lowering the bottom of the filling hoppers with respect to the top of the pockets. To this end, each of

hoppers

47 and 48 individually is movable toward and away from drum as generally indicated by arrow 56. In this way the height of the truncated triangular cross section may be varied and thus the quantity of material dispensed adjusted.

After passing the filling hoppers, the pockets move to the leveling apparatus 19. The leveling apparatus comprises three

resilient wiper blades

57, 58 and 59 in a mounting 60. Each of the blades is resilient. The first of the blades 57 is positioned so that its bottom edge 61 will project into each cavity as the cavity passes the wiper blade. This is illustrated in dotted lines in FIG- URE 4 and in full lines in FIGURE 5. Thus the first wiper blade not only spreads out the mound of product left by the filling apparatus 18 and generally fills all of the voids at the sides of that mound, but, in addition, leaves a small void across the top of each pocket with the pocket not being level full. This small void which is left by the first wiper blade 57 then is filled by the subsequent wiper blades scraping loose particulate rria= terial from the various surfaces of the film extending along the periphery of the drum. The second wiper blade 58 is pressed less firmly against the film surface, and the third wiper blade 59 moves lightly across the surfaces of the film. I have discovered that the foregoing filling and leveling procedures not only result in a relatively simple apparatus structure for carrying them out, but result also in remarkably uniform packages both as to quantity and evenness of filling.

The liquid-applying apparatus 24 is best illustrated in FIGURE 6. It is positioned at a point at which the film from roll 21 makes a relatively vertical run between rollers 22 and 23. A wick 64 is positioned so that its upper end 65 contacts a face 66 of the film from roll 21. End 65 contacts face 66 across the entire transverse width thereof. The lower end of wick 64 is immersed in a bath 67 of water in container 68. At each end of container 68 are a pair of arms 69 pivotally connected to container 68 by bolts 70. A pair of cross bars 71 extend between arms 69. Cross bars 71 are clamped together on opposite sides of wick 64 by bolts 72. This mounting is such that when the machine is operating, wick 64 is held in contact with face 66 of the film by its weight. If the machine is to be stopped for any reason, arms 69 are pivoted away from face 66 so that end 65 of the wick no longer contacts the film.

The surface 74 of the bath 67 is maintained at a predetermined elevation by a float valve 75. Water is supplied to float valve 75 through a hose 76. A second hose 77 connects float valve 75 and container 68. A bracket 78 is affixed to float valve 75 and has a slot 79 therein through which a mounting bolt extends. Bolt 80 is aflixed to a portion of the frame (not shown) of the machine. By loosening bolt 80, float valve 75 may be raised or lowered to correspondingly raise or lower the surface 74 of the liquid in bath 67.

By raisin the surface 74 of the bath, the amount of liquid that is applied to surface 66 of the film will be increased. correspondingly, by lowering the surface 74 of the bath 67, the amount of liquid applied to face 66 will be decreased. For any given setting of the height of the surface 64- (or the distance from the surface 74 to the end 65 as measured along wick 6 a remarkably even moistening of the face 66 of the film will take place.

As best illustrated in FIGURE 7, roller 27 is journa-led on a shaft 83 affixed to a mounting 84. Roller 27 is free to rotate as the drum 10 and the film thereon move in the direction indicated by arrow 12. However, because of the angular positioning of the axis of shaft 83 with respect to the axis of pipe 45 of the drum, the roller 27 will act to push inwardly on the film in the direction indicated by arrow 85. A similar roller (not shown) on the opposite side of drum ll) pushes in the reverse direction of arrow 85. These forces applied 'by the rollers serve to loosen the packages 34 of product from the cavities in which they were formed.

With some films, cling can be obtained and the film drawn into the cavities to form pockets without first heating the film. Some PVA films have sufficient plasticizer that they are stretchable at room temperature. With these films the roller 17 need not be heated. Also, the film from roll 16 may be softened by adding moisture thereto to render it sufliciently pliant that it need not be heated. A liquid-applying device such as 24 may as shown in FIG. 1A, be employed to moisten the film between roll 16 and roller 17 to render the film soft (and tacky if desired for adhesion purposes).

The first wiper 57 may be replaced by a roller positioned to contact the top of the pile of product and press it into the cavities. The roller could extend the entire width of the drum, parallel thereto. It would have a sufficiently soft surface, e.g. soft rubber, so that its surface would push down into the pockets as does wiper 57.

I claim:

1. A packaging machine for sealing product in a film, said machine including: a carrier trained for movement along a given path, said carrier having a line of cavities in said path, each of said cavities having a vacuum port therein, said carrier having a relatively smooth peripheral surface surrounding each cavity; means connected to said carrier to move said carrier in a given direction along said path; means to supply a first continuous ribbon of said fihn to be drawn over the carrier and to apply it over each cavity and the surface thereabout at a point along said path; means connected to said ports to apply a vacuum to the port of each cavity after the cavity passes said point to draw the film into the cavity and define a pocket in the film; means to fill said pockets with product; means beyond said filling means in said direction to lay a second ribbon of film over the pockets and portions of the first ribbon about the pockets and to press the two films together to enclose the product in each pocket in film to form a package, the last means including a device to apply a liquid to the face of the second film, at least in the areas which will contact the first film, in a quantity sutlicient to render the second film tacky without destroying the film; and means to remove each package from its cavity.

2. A packaging machine for sealing product in a thermoplastic liquid-soluble film, said machine including: a drum having its cylindrical axis generally horizontal :and rotatable about said axis, said drum having a circumferential line of cavities thereabout, each of said cavities having a vacuum port therein, said drum having a relatively smooth peripheral surface surrounding each cavity; means connected to said drum to rotate said drum in a given direction; film laying means to lay a first continuous ribbon of said film over each cavity and the surface thereabout as the cavity passes a point preceding, with respect to said direction of rotation, the top of said drum, said film laying means including a roller about which the film passes, said roller having its axis parallel to the drum axis and positioned to press the film against said surface at said point, said roller being heated sufficiently to soften said film; means connected to said ports to apply a vacuum to the port of each cavity immediately after the cavity passes said point to draw the heat-softened film into the cavity and define a pocket in the film; means in the vicinity of the top of the drum to fill said pockets level full of product; means beyond said filling means in said direction to lay a second ribbon of film over the pockets and portions of the first ribbon about the pockets and to press the two films together to enclose the product in each pocket in film to form a package, the last means including a device to apply a solubilizing liquid to the face of the second film, at least in the areas which will contact the first film in a quantity sufiicient to render the second film tacky Without destroying the film, and a heated roller pressing the second ribbon against the first; and means to remove each package from its cavity.

3. A packaging machine for sealing product in a thermoplastic liquid-soluble film, said machine including: a drum having its cylindrical axis generally horizontal and rotatable about said axis, said drum having a circumferential line of cavities thereabout, each of said cavities having a vacuum-port therein, said drum having a relatively smooth peripheral surface surrounding each cavity; means connected to said drum to rotate said drum in a given direction; film laying means to lay a first continuous ribbon of said film over each cavity and the surface thereabout as the cavity passes a point preceding, with respect to said direction of rotation, the top of said drum, said film laying means including a roller about which the film passes, said roller having its axis parallel to the drum axis and positioned to press the film against said surface at said point, said roller being heated sufiiciently to soften said film; means connected to said ports to apply a vacuum to the port of each cavity immediately after the cavity passes said point to draw the heat-softened film into the cavity and define a pocket in the film; means in the vicinity of the top of the drum to fill said pockets level full of product; means beyond said filling means in said direction to lay a second ribbon of film over the pockets and portions of the first ribbon about the pockets and to press the two films together to enclose the product in each pocket in film to form a package, the last means including a device to apply a solubilizing liquid to the face of the second film, at least in the areas which will contact the first film in a quantity sufficient to render the second film tacky without destroying the film, said device including a generally vertical wick, the upper end of the wick being in contact with said face across the width thereof, means for holding a bath of said liquid, with the lower end of the Wick immersed in said bath, and means to maintain the surface of said bath at a predetermined distance from the upper end of the wick; and means to remove each package from its cavity.

4. A packaging machine for sealing product in a thermoplastic liquid-soluble film, said machine including; a drum having its cylindrical axis generally horizontal and rotatable about said axis, said drum having a circumferential line of cavities thereabout, a separate cupshaped plastic insert defining the inner portion of each cavity, said insert being adjustable toward and away from the open side of the cavity, a fluid passageway about the side of the insert between the top and bottom thereof, each of said cavities having a vacuum port therein below said insert, said drum having a relatively smooth peripheral surface surrounding each cavity; means connected to said drum to rotate said drum in a given direction; film laying means to lay a first continuous ribbon of said film over each cavity and the surface thereabout as the cavi y passes a point preceding, with respect to said direction of rotation, the top of said drum, said film laying means including a roller about which the film passes, said roller having its axis parallel to the drum axis and positioned to press the film against said surface at said point, said roller being heated sufiiciently to soften said film; means connected to said ports to :apply a vacuum to the port of each cavity immediately after the cavity passes said point to draw the heat-softened film into the cavity and define a pocket in the film; means in the vicinity of the top of the drum to fill said pockets level full of product; means beyond said filling means in said direction to lay a second ribbon of film over the pockets and portions of the first rib'bon about the pockets and to press the two films together to enclose the product in each pocket in film to form a package, the last means including a device to apply a solubilizing liquid to the face of the second film, at least in the areas which will contact the first film in a quantity sufficient to render the second film tacky without destroying the film; and means to remove each package from its cavity.

5. A packaging machine for sealing particulate product in a thermoplastic liquid-soluble film, said machine including: a drum having its cylindrical axis generally horizontal and rotatable about said axis, said drum having a circumferential line of cavities thereabout, each of said cavities having a vacuum port therein, said drum drum having a relatively smooth peripheral surface surrounding each cavity; means connected to said drum to rotate said drum in a given direction; film laying means to lay a first continuous ribbon of said film over each cavity and the surface thereabout as the cavity passes a point preceding, with respect to said direction of rotation, the top of said drum, said film laying means including a roller about which the film passes, said roller having its axis parallel to the drum axis and positioned to press the film against said surface at said point, said roller being heated sufficiently to soften said film; means connected to said ports to apply a vacuum to the port of each cavity immediately after the cavity passes said point to draw the heat-softened film into the cavity and define a pocket in the film; means in the vicinity of the top of the drum to fill said pockets level full of product, the last means including a filling spout movable toward and away from said drum to regulate the amount of particulate product dispensed, and a plurality of wiper blades extending parallel to said axis in said direction from said spout, said blades being positioned to contact said surface of said drum, the blade nearest said spout being formed of a flexible material and being positioned so that the portion thereof in said line will project below said surface; means beyond said filling means in said direction to lay a second ribbon of film over the pockets and portions of the first ribbon about the pockets and to press the two films together to enclose the product in each pocket in film to form a package, the last means including a device to apply a solubilizing liquid to the face of the second film, at least in the areas which will contact the first film in a quantity sufficient to render the second film tacky without destroying the film; and means to remove each package from its cavity.

6. A packaging machine for sealing product in thermoplastic liquid-soluble film, said machine including: a drum having its cylindrical axis generally horizontal and rotatable about said axis, said drum having a circumferential line of cavities thereabout, each of said cavities having a vacuum port therein, said drum having a relatively smooth peripheral surface surrounding each cavity; means connected to said drum to rotate said drum in a given direction; film laying means to lay a first continuous ribbon of said film over each cavity and the surface thereabout as the cavity passes a point preceding, with respect to said direction of rotation, the top of said drum, said film laying means including a roller about which the fdm passes, said roller having its axis parallel to the drum axis and positioned to press the film against said surface at said point, said roller being heated sufiiciently to soften said film; means connected to said ports to apply a vacuum to the port of each cavity immediately after the cavity passes said point to draw the heat-softened film into the cavity and define a pocket in the film; means in the vicinity of the top of the drum to fill said pockets level full of product; means beyond said filling means in said direction to lay a second ribbon of film over the pockets and portions of the first ribbon about the pockets and to press the two films together to enclose the product in each pocket in film to form a package, the last means including a device to apply a solubilizing liquid to the face of the second film, at least in the areas which will contact the first film in a quantity sufiicient to render the second film tacky without destroying the film; and means to remove each package from its cavity, the last means including rollers in contact with the outer face of the second ribbon of film at each side of said line of cavities, said rollers being rotatable about axes angularly disposed to the axis of the drum to push the film toward said line of cavities and loosen said film and pockets from the drum.

7. A packaging machine for sealing a particulate product in a thermoplastic liquid-soluble film, said machine including: a drum having its cylindrical axis generally horizontal and rotatable about said axis, said drum having a circumferential line of cavities thereabout, a separate cup-shaped plastic insert defining the inner portion of each cavity, said insert being adjustable toward and away from the open side of the cavity, a fluid passageway about the side of the insert between the top and bottom thereof, each of said cavities having a vacuum port therein below said insert, said drum having a relatively smooth peripheral surface surrounding each cavity; means connected to said drum to rotate said drum in a given direction; film laying means to lay a first continuous ribbon of said film over each cavity and the surface thereabout as the cavity passes a point preceding, with respect to said direction of rotation, the top of said drum, said film laying means including a roller about which the film passes, said roller having its axis parallel to the drum axis and positioned to press the film against said surface at said point, said roller being heated sufficiently to soften said film; means connected to said ports to apply a vacuum to the port of each cavity immediately after the cavity passes said point to draw the heat-softened film into the cavity and define a pocket in the film; means in the vicinity of the top of the drum to fill said pockets level full of product, the last means including a filling spout movable toward and away from said drum to regulate the amount of particulate product dispensed, and a plurality of wiper blades extending parallel to said axis in said direction from said spout, said blades being positioned to contact said surface of said drum, the blade nearest said spout eing formed of a flexible materialand being positioned so that the portion thereof in said line will project below said surface; means beyond said filling means in said direction to lay a second ribbon of film over the pockets and portions of the first ribbon about the pockets and to press the two films together, to enclose the product in each pocket in film to form a package, the last means including a device to apply a solubilizing liquid to the face of the second film, at least in the areas which will contact the first film in a quantity sufficient to render the second film tacky without destroying the film, and a heated roller pressing the second ribbon against the first, said device including a generally vertical wick, the upper end of the wick being in contact with said face across the width thereof, means for holding a bath of said liquid, with the lower end of the wick immersed in said bath, and means to maintain the surface of said bath at a predetermined distance from the upper end of the wick; and means to remove each package from its cavity, the last means including rollers in contact with the outer face of the second ribbon of fihn at each side of said line of cavities, said rollers being rotatable about axes angularly disposed to the axis of the drum to push the film toward said line of cavities and loosen said film and pockets from the drum.

8. In a machine for use in preparing pockets in a film for receiving product and having a carrier with a line of cavities over which a ribbon of film is laid with the film being drawn into the cavities to define pockets to receive the product, the improvement including: providing the surface of said carrier about the cavities with a relatively smooth surface; and means to press said film against said surface prior to drawing said film into said cavities to cause the film edges to cling to the surface; said machine being characterized by the film being free of mechanical restraint of the film edges and the film being held against shifting by the cling of the film and the carrier.

9. In a packaging machine according to claim 8, means to apply to the film a solvent for the film in a quantity sufiicient to soften the film without destroying the film.

10. In a packaging machine for sealing product in thermoplastic films and having a drum with peripheral cavities over which a ribbon of film is laid by a roller about a portion of which the film travels with the film being drawn into the cavities by vacuum to define pockets to receive the product, the improvement including: said film being free of mechanical restraint of the film as the vacuum is applied; said drum having a polished peripheral surface surrounding said cavities; said roller being heated to a temperature at which said film is substantially plastic and positioned to press the film against said surface at about the same relative position at which the vacuum is first applied to the cavity.

11. The method of forming pockets for receiving prodnot to be sealed in thermoplastic film using a machine having a drum with peripheral cavities over which a ribbon of film is laid by a roller about a portion of which the film travels with the film being drawn into the cavities by vacuum to define pockets to receive the product, said method including: polishing the surface of the drum surrounding said cavities; allowing said film to move about said drum free of mechanical restraint of the film as the vacuum is applied; and heating said film to a substantially plastic state and pressing the heated film against said surface at least as early as at about the same relative posi tion at which the vacuum is first applied to the cavity.

12. In a packaging machine for sealing particulate product in thermoplastic films and having a drum moving in a given direction about its axis and having peripheral cavities over which a ribbon of film is laid with the film being drawn into the cavities to define pockets to receive the product, the improvement including: a filling spout for said particulate material having a dispensing opening adjacent the upper portion of the drum, said spout being movable toward and away from said drum to regulate the amount of product dispensed, and a plurality of wiper blades extending parallel to said axis in said direction from said spout, said blades being positioned to contact the ribbon engaging said surface of said drum at successive distances from the spout, the blade nearest said spout being formed of a flexible material and being positioned so that a portion thereof will project into said cavities, the next blade being pressed less firmly against the film surface, and a further blade being positioned so as to move lightly across the surfaces of the film.

13. In a packaging machine for sealing particulate product in thermoplastic films and having a drum with peripheral cavities over which a ribbon of film is laid with the film being drawn into the cavities to define pockets to receive the product, the improvement including: means adjacent the top of said drum to form a mound of material in each pocket of a volume less than the capacity of the pocket but of a given height greater than the top of the pocket; first blade means thereafter pro jecting into said pockets to flatten the top of said mound to a level below the top of the pocket with at least a portion of the excess material filling any voids about the sides of the pocket; and additional blade means thereafter to wipe the film surrounding the pocket and level off any material thus wiped into the pocket to the level of the top of the pocket.

14. The method of filling with particulate material the pockets of a packaging machine having a drum with peripheral cavities over which a ribbon of film is laid by a roller about a portion of which the film travels with the film being drawn into the cavities by vacuum to define pockets to receive the product, said method comprising the steps of: as each pocket is in the vicinity of the top of the drum forming a mound of material in each pocket of a given height greater than the top of the pocket but of a total volume less than the volume of the pocket; thereafter projecting a blade member into said pocket to flatten the top of the mound to a level below the top of the pocket with at least a portion of the excess material filling any voids about the sides of the pocket; and thereafter wiping the film surrounding the pocket and leveling off the material in the pocket to the level of the top of the pocket.

15. In a packaging machine wherein product to be packaged is deposited in pockets in a first ribbon of film and thereafter a second ribbon of film is laid over the first ribbon with at least portions of one face of said first ribbon in contact with corresponding portions of a face of the second ribbon and the two affixed together to form a package, the improvement including: said films being liquidsoluble; means to move one of said films along a generally vertical path prior to bringing said films together; a generally vertical wick, the top of said wick being positioned to contact said portions of the face of said one film as said face moves along said path; means forming a bath of said liquid about the bottom of the wick with said bottom immersed in said bath; and means to maintain the surface of said bath a predetermined distance from the top of the wick.

16. The improvement in the method of packaging product in film wherein the product to be packaged is deposited in pockets in a first ribbon of film and thereafter a second ribbon of film is laid over the first ribbon with at least portions of one face of said first ribbon in contact with corresponding portions of a face of the second ribbon and the two affixed together to form a package, said improvement including utilizing films that are liquid-soluble; moving one of said films along a generally vertical path prior to bringing said films together; wicking said liquid onto said portions of the face of said one film as said film moves along said path from a bath of said liquid located below said portions of said film at the time the liquid is applied thereto; and maintaining the surface of said bath a predetermined distance from said portions at said time.

17. In a packaging machine for sealing product in thermoplastic films and having a drum with peripheral cavities over which a ribbon of film is laid with the film being drawn into the cavities to define pockets to receive the product, the improvement including: said drum having a plurality of pockets extending inwardly from the peripheral face thereof and positioned in a circumferential row about the drum; a separate cup-shaped insert in each pocket and spaced inwardly from the surface of the drum surrounding the pockets, said inserts being spaced from the walls of the drum defining said pockets to provide a fluid passageway about the side of the insert between the top and bottom of the insert; means to releasably affix said inserts in said pockets at varying distances from the bottom portion of each of said pockets; and fluid passages in the drum communicating with the pockets below the inserts therein.

18. In a packaging machine for sealing particulate product in thermoplastic films and having a drum rotating about a horizontal axis and having peripheral cavities over which a ribbon of film is laid with the film being drawn into the cavities to define pockets to receive the product, the improvement including: a filling spout for said particulate material having a dispensing opening adjacent the upper portion of the drum, said spout being movable toward and away from said drum to regulate the amount of product dispensed to match quantity to capacity of pockets.

19. In a packaging machine for sealing particulate product in thermoplastic films and having a drum rotating about a horizontal axis and having peripheral cavities over which a ribbon of film is laid with the film being drawn into the cavities to define pockets to receive the product, the improvement including: a filling spout for said particulate material having a dispensing opening adjacent the upper portion of the drum, said spout being movable toward and away from said drum to regulate the amount of product dispensed to match quantity to capacity of pockets; and means to level off the particulate material in the pockets.

20. In a packaging machine for sealing particulate product in thermoplastic films and having a drum with peripheral cavities over which a ribbon of film is laid with the film being drawn into the cavities to define pockets to receive the product, the improvement including: means adjacent the top of said drum to form a mound of material in each pocket of a given height greater than the top of the pocket, said means being adjustable toward and away from the top of the drum to vary the height of the mound to match the quantity of material to the pocket capacity; means thereafter, to flatten the top of said mound to a level below the top of the pocket with at least a portion of the excess material filling any voids about the sides of the pocket; and means thereafter to wipe the film surrounding the pocket and level off any material thus wiped into the pocket to the level of the top of the pocket.

21. In a packaging machine wherein product to be packaged is deposited in pockets in a first ribbon of film and thereafter a second ribbon of film is laid over the first ribbon with at least portions of one face of said first ribbon in contact with corresponding portions of a face of the second ribbon and the two affixed together to form a package, the improvement including: said films being liquid-soluble; means to move one of said films along a predetermined path prior to bringing said films together; a wick having one end positioned to contact said portions of the face of said one film as said face moves along said path; means forming a bath of said liquid about the other end of the wick; and means to maintain the surface of said bath at a given elevation.

References Cited by the Examiner UNITED STATES PATENTS 2,103,386 12/1937 Salfisberg 53180 X 2,125,874 8/1938 Anderson 53141 X Goedike 101-147 Clunan 53141 X Cloud 53180 X Truscott 53141 X Keller 53184 X Cloud 53180 X Podlesak 53-180 X Hansen et a1 53180 X Malicay 53180 Gex et al. 53180 X ROBERT A. LEIGHEY, Examiner.

FRANK E. BAILEY, Primary Examiner.

Claims

15. IN A PACKAGING MACHINE WHEREIN PRODUCT TO BE PACKAGED IS DEPOSITED IN POCKETS IN A FIRST RIBBON OF FILM AND THEREAFTER A SECOND RIBBON OF FILM IS LAID OVER THE FIRST RIBBON WITH AT LEAST PORTIONS OF ONE FACE OF SAID FIRST RIBBON IN CONTACT WITH CORRESPONDING PORTIONS OF A FACE OF THE SECOND RIBBON AND THE TWO AFFIXED TOGETHER TO FORM A PACKAGE, THE IMPROVEMENT INCLUDING: SAID FILMS BEING LIQUIDSOLUBLE; MEANS TO MOVE ONE OF SAID FILMS ALONG A GENERALLY VERTICAL PATH PROR TO BRINGING SAID FILMS TOGETHER; A GENERALLY VERTICAL WICK, THE TIP OF SAID WICK BEING POSITIONED TO CONTACT SAID PORTIONS OF THE FACE OF SAID ONE FILM AS SAID FACE MOVES ALONG SAID PATH; MEANS FORMING A BATH OF SAID LIQUID ABOUT THE BOTTOM OF SAID WICK WITH SAID BOTTOM IMMERSED IN SAID BATH; AND MEANS TO MAINTAIN THE SURFACE OF SAID BATH A PREDETERMINED DISTANCE FROM THE TOP OF THE WICK.