Method And Apparatus For Forming And Filling Pouches

Abstract

A machine for forming and filling pouches from a continuous supply of web material has a station forming said web into a continuous train of poucnes, each pouch having an upwardly opening side, a station for filling the pouches as they are carried around the periphery of a carrier wheel, and a station for sealing the open side of each pouch and separating the pouches into individual packets. The carrier wheel has a rocker assembly for rocking each pouch after it is filled, settling the material therein and forming a more compact package. A filling wheel is located above the carrier wheel and rotates therewith to automatically insert filling tubes into the pouches, deposit a charge of material to be packaged into each pouch, and withdraw the filling tubes from the pouches as the carrier wheel rotates. The pouches are opened to receive the filling tubes through the cooperation of vacuum nozzles which grip one side of each pouch, air jets directed into the pouches, and the rocker assembly which supports the pouches as they are rotated by the carrier wheel.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of forming and filling packages, and more particularly to a method of forming packages as a continuous train of pouches having an upwardly opening side, filling the pouches through the open side and sealing the pouches to produce individual packages.

2. The Prior Art

Machines for forming pouches from a continuous web, and filling them are well known. For example, such a machine is disclosed in Cloud U.S. Pat. No. 3,344,576. Such machines have performed in a generally satisfactory manner, but it is desirable to improve the manner in which the pouches are opened prior to filling, to permit increased operating speeds, and it is also desirable to devise a way of causing the material placed in the pouches to settle as much as possible to the bottom thereof, so as to form the most compact package possible.

As the cost of the web material of which the packages are formed is considerable, it is desirable to produce packages with as little material as possible.

SUMMARY OF THE INVENTION

Accordingly, it is a principal object of the present invention to provide a method and apparatus for forming and filling packages having means for quickly and efficiently opening the package to receive a product thereinto.

Another object of the present invention is to provide a method and apparatus for forming and filling a package, in which a more compact package is achieved.

These and other objects and advantages of the present invention will become manifest upon an examination of the following description and the accompanying drawings:

In one embodiment of the present invention there is provided a method comprising the steps of providing a supply of web material adapted to be formed into a continuous train of pouches having an upper open side, opening the upper side of each said pouch, filling each said pouch with a predetermined quantity of a product, settling the product within the pouch, and sealing the open edge of said pouch to provide a complete enclosed package containing the product.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will now be made to the accompanying drawings in which:

FIG. 1 is a plan view of apparatus incorporating an exemplary embodiment of the present invention, which performs the method of the present invention;

FIG. 2 is a vertical cross-sectional view of a portion of the apparatus illustrated in FIG. 1, taken through the plane II--II;

Fig. 3 is a plan view of the carrier wheel of FIG. 1, partly in cross-section, with the filling wheel removed;

FIG. 4 is a side elevational view, partly in cross-section, of a portion of the apparatus illustrated in FIG. 3, as viewed from the plane IV--IV;

FIG. 5 is a side elevational view partly in cross-section, of a portion of the apparatus illustrated in FIG. 4, showing a pouch in condition to be filled;

FIG. 6 is an illustration showing a freshly filled pouch in full line, and a pouch in which the product has been settled in phantom line;

FIG. 7 is a plan view partly in cross-section of the table which supports the carrier wheel; and

FIG. 8 is a side elevational view of a portion of the apparatus illustrated in FIG. 7, as seen from the plane VIII-VIII.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, FIG. 1 illustrates a plan view of a complete packaging machine which utilizes a roll 10 of web material 9, and successively forms the web material 9 into a train of connected pouches, fills the pouches with a product, settles the product in the pouches, seals the open edge of the pouches to form a train of filled packets, and separates the individual packets from the train. Some of the apparatus of FIG. 1 is well known in the art, and is illustrated in FIG. 1 only to show its cooperation with apparatus embodying the present invention. In particular, the apparatus for forming a train of connected pouches having an open side from a roll of web material is described in Cloud U.S. Pat. No. 3,505,776. As described in that patent, the roll 10 contains a supply of web material of any suitable type, and is preferably of the type coated on at least one side with a sealable material such as plastic or other suitable adhesive. The web 9 is unrolled from the roll 10 through a series of successive rollers 12, 14, 16 and 18, and the tension on the web is controlled by a brake unit 20. A paper plow 38 is supported by a table 24, and folds the web 9 upwardly into a V-shaped cross-section, with the crease at the bottom, as described in the aforementioned Cloud U.S. Pat. No. 3,505,776. Then the web 9 passes over guide rollers 40 and 42 to a heat sealing means 44. The heat sealing means is provided for the purpose of sealing together a thin margin adjacent the bottom folded edge of the web 9, so as to maintain the web in tightly folded condition. As more fully described hereinafter, drive rollers 74 and 76 engage the top heat sealed portion after the pouches are filled and the open end is sealed.

Following the sealer means 44, the web 9 passes around a segmented drum 46 which functions as a vertical sealer, to seal together the sides of the folded web 9 along spaced vertical bands, to form a train of pouches having an open upper side. The drum 46 is also described in the aforesaid Cloud U.S. Pat. No. 3,505,776.

The web 9 thereafter passes over a roll 60 which is mounted on a shaft 62 supported in an adjustable relation in a slot 63 provided in a bracket 64. The bracket 64 is bolted to the surface of the table 24. Adjustment of the position of the roll 60 relative to the bracket 64 permits synchronization between the operation of the drum 46 and the operations taking place at the filling station.

Following the roll 60, the web 9 passes over a roll 65 and then through the nip of a pair of drive rollers 66 and 67 which are driven (by means not shown) so as to pull the web 9 from the supply roll 10.

Following the drive rolls 66 and 67 the web 9 passes over an idler roller 68 and then around the periphery of a circular filling station 70. As the web 9 passes around the filling station 70 the pouches are successively opened, filled with a quantity of product such as granulated sugar or the like, and then manipulated so as to settle the product in the pouches. Thereafter the web 9, now comprising a series of filled pouches 71, leaves the filling station 70 and passes through an upper sealing station 72 at which the upper edge of the pouches is sealed to form individual connected packets 80. Apparatus for making the upper seal is described in Cloud et al U.S. Pat. No. 3,344,576. Thereafter the train of filled and sealed packets 80 passes through a second drive station incorporating a drive roller 74 and a spring biased idler roller 76. The rollers 74 and 76 bear on the upper margin of the web, which is maintained in a relatively planar condition, as a result of the operation of the sealing means 44, so that there is no risk of crushing the material with which the packets 80 are filled, nor of rupturing the packets as a result of application of driving pressure thereto.

Following the second drive station, the train of packets 71 is twisted through 90.degree. and then passed through a cutting station 78 having a plurality of cutting blades adapted to engage the vertical sealed portions formed by the drum 46, and separate the web into a plurality of separate packets 80. A suitable cutting station is described in Cloud U.S. Pat. No. 3,597,898. Thereafter, the individual separate packets 80 are transported away by means of a conveyor belt 82.

Referring now to FIGS. 3 and 4, the arrangement of the web 9 as it passes by the roller 68 and enters the vicinity of the filling station 70 is illustrated in detail. Upstream of the roller 68 the web 9 is flat, with the opposite sides of the folded web lying closely together. After the web 9 rounds the roller 68, however, the pouches 71 are caused to open, so that they are prepared to receive a charge of a filling product. The opening of the pouches is facilitated by several separate means which cooperate to insure that the pouch is opened quickly and with certainty, and maintained in open condition for as long as necessary.

A pair of air nozzles 84 and 86 are located above the path of the web 9 just downstream of the roller 68. The nozzle 84 is located above the nozzle 86 (FIG. 4) and both are directed downwardly toward the upper end of the pouch 71. The stream of the nozzle 84, in addition to being located above that of the nozzle 86, is also spaced slightly inwardly thereof, relative to the center of the filling station 70. Both nozzle 84 and 86 are connected to a source of air at a pressure greater than atmospheric, so that both direct streams of air downwardly and inwardly toward the upper end of the pouch 71.

The web 9 is folded so that the radially inner edge 88 as the web 9 circles the filling station 70, overlaps the opposite edge 90 and extends slightly thereabove. There is, therefore, a portion 91 on the radially inner side of the folded web, which is positioned to catch the air stream from the nozzles 84 and 86 so as to be forced inwardly thereby, away from the other side of the folded web. The air stream not only catches this portion and forces it inwardly but also enters into the pouch, billowing and puffing it so as to open its top unsealed side.

As the pouch 71 is opened by the combined action of the nozzles 86 and 84, its radially inner side comes into association with a vacuum nozzle 92. The nozzle 92 is formed from a length of longitudinal collapsable tubing so that the length of the nozzle is responsive to the pressure of the air therein. When the interior of the nozzle 92 is at atmospheric pressure, the nozzle is extended, as illustrated in FIG. 3. When the pressure is reduced, however, below atmospheric pressure, the nozzle has a tendency to collapse, so that the free end of the nozzle is drawn inwardly relative to the center of the filling station 70. At the same time, however, the radially inner side of the pouch 71 becomes attached to the mouth of the nozzle 92, and it is thereby drawn inwardly, by the free end of the nozzle, which also contributes to opening the upper side of the pouch preparatory to filling.

One additional factor enhances the ability of the pouch 71 to open its upper side as it proceeds around the filling station 70, and that is that the lower edge of the web 9 is caused to proceed around the filling station 70 following a path having a larger radius of curvature than the upper edge of the web. Therefore, the lower edge of the web 9 is generally under a slight tension, while the upper edge, being free of tension, is free to buckle slightly relative to the bottom edge. This buckling tends to move the vertical sides of each pouch closer together, especially near the upper edge, and permits the upper side of each pouch to open with the opposite surfaces of the pouch moving apart. This feature is best illustrated in FIGS. 4 and 5.

As shown in FIG. 4, the web 9 is just rounding the roller 68 and has not yet come into contact with a vacuum nozzle 92. As shown in FIG. 5, however, the nozzle 92 is engaged with the radially inner surface of the pouch 71, and has drawn that side inwardly. The lower edge of the web 9 is maintained in an outward position by an arm 94, while the vacuum nozzle 92 draws the upper edge of the web radially inwardly, where it traverses a path having a shorter radius of curvature, and therefore a shorter arcuate length, than the path of the lower edge. The outer extremity of the arm 94 is located radially outwardly of the vacuum nozzle 92. Both of the arms 94 and the vacuum nozzle 92 are carried by a carrier wheel 95 disposed at the filling station 70, and so the upper edge of the web follows a path of lesser radius than the lower edge.

The several factors described above combine to open each of the pouches 71 of the web 9, and to maintain them in open position as the web 9 circles the wheel 95.

As best seen in FIG. 3, the carrier wheel 95 has a plurality of land members 100 equally spaced around the periphery thereof, each of which engages a vertical seal separating two of the pouches 71. The lands 100 are each pivotally mounted on the wheel 95 by means of brackets 104, each of which mounts a shaft 102 on which a land 100 is supported. The attitude of the lands 100 therefore influences the attitude of the pouches 71. As described above, downstream from the roller 68, where the lands 100 first engage the web 9, that attitude is such that the lower edge of the web occupies a radially outer position. This condition of the lands 100 is assured by a cam 98 mounted on the surface of the table 24, and which maintains the position of follower rollers 96, which are disposed on the inner ends of the arms 94. The lands 100, the arms 94, and the cam follower rollers 96 together form rocker assemblies which cooperate with the cam 98 to rock the pouches 71 following the filling operation, as described hereinafter.

After the pouches 71 rotate with the wheel 95 for about 60.degree.from the place where the web first engages the lands 100, during which filling tubes are lowered into the pouches, the pouches 71 begin to be filled, and the filling operation continues for approximately 90.degree. of the rotation of the wheel 95. Thereafter about 30.degree. of rotation of the wheel 95 is provided for removing the filling tubes from the pouches. The area where filling takes place is indicated in FIG. 3 by the ovals 154, shown in dashed lines, which describe the positions taken by filling tubes during the filling operation.

Subsequently, the pouches 71 are caused to be rocked or shifted in a way which encourages the product deposited in a pouch to shift and settle in the pouch so as to form a compact mass at the bottom portion of the pouch. To this end, as the web 9 reaches a point approximately 180.degree. from the position of the roller 68, the upper portion of the web is forced outwardly, and the lower portion of the web is drawn inwardly, by action of the rocker assemblies. The change in altitude of a filled pouch is best illustrated in FIG. 6, where the pouch 71 is shown in full line in the attitude assumed as it is filled. During the rocking operation, however, it is caused to assume a different attitude, as illustrated in phantom, in which the lower portion of the pouch 71 is drawn inwardly and the upper portion is forced outwardly relative to the wheel 70. This causes the upper edge of the web, with the open side of the pouches, to be placed under tension, and releases the tension from the lower edge of the web, allowing the lower portions of pouches 71 to bulge in the same manner as its upper portion was caused to bulge during filling. The bulging of the lower portion of the pouch permits the product to move downwardly in the pouch, and the two illustrations of FIG. 6 show that the center of gravity of the pouch is lowered when the pouch has been rocked to the attitude shown in phantom.

The change in attitude of the pouches is filled by camming the arm 94 inwardly and outwardly relative to the carrier wheel 95, via the follower roller 96.

The construction of the wheel 95 is best illustrated in FIG. 2. A bearing assembly 106 is supported on the surface of the table 24 and supports a shaft 108 which is driven from below (by means not shown). The wheel 95 is attached to a central hub 110, and the hub is secured to the upper end of the shaft 108. The bottom surface of the wheel 95 is provided with a plurality of grooves 112 which are provided for the various vacuum nozzles 92. Each of the grooves 112 communicates with an individual nozzle 92, and leads inwardly therefrom terminating at a position spaced outward slightly from the hub 110. A cover plate 114, secured to the bottom of the wheel 95, encloses the bottom surface of the grooves 112, except for a plurality of apertures 116, located adjacent the radially inner end of each of the grooves 112. The cover 114 is supported by a wear plate 118 and the wear plate, the cover 114 and the wheel 95 are secured together by means of screws 120. The wear plate 118 has a plurality of apertures aligned with the apertures 116, and is supported on a bearing surface 122 which is supported on the surface of the table 24 by a tubular support 124. The bearing surface 122 is provided with a groove 126 in its upper surface which extends in a circular arc in alignment with some of the apertures 116. The groove 126 is connected, by means of a bore 128, to a tube 130 which is connected to a partial vacuum, having a pressure less than atmospheric pressure, so that the vacuum nozzles 92 are connected with the vacuum whenever their apertures 116 are aligned with the groove 126. The arcuate length of the groove 126 extends through an angle, relative to the shaft 108, and determines when the nozzles 92 are each connected to the vacuum and when they become disconnected therefrom, as the wheel 95 rotates. The groove 126 is positioned so that the nozzles become connected to the vacuum at about a time they first engage with the inner side of the folded web 9, and are disconnected from the vacuum at about a time that the filled packets leave the wheel 95 on their way to the station 72.

Referring to FIG. 7 the shape of the cam 98 is illustrated. It is seen to be generally circular in form, but with two flattened portions 132 and 134 adjacent the places where it is desired to rock the contents of the pouches 71. A camming plate 136 in the form of an L-shaped bar is bolted to the surface of the table 24 adjacent the flattened surface 132, and a similar camming plate 138 is bolted to the surface of the table 24 adjacent the flattened portion 134. The camming plates 136 and 138 function to cam the rollers 96 inwardly so as to rock the bands 100 as shown at the right side of FIG. 2, as the pouches pass the locations of the plates 136 and 138. As illustrated in FIG. 7, this occurs twice for each pouch, during its travel around the wheel 95. Between the two plates 136 and 138 is a location where the circular outer surface of the cam 98 is resumed, which causes tension to be restored to the bottom edge of the web and released from the upper edge of the web, causing the filled pouch to again slacken at the top. By means of the successive slackening of the upper and lower portions of the pouches, the product placed into the pouches is shifted downwardly therein and forms a compact mass within the lower portion of each pouch.

When the product deposited into the pouches is very light and powdery, it may be preferable to avoid abrupt transitions between the circular and flat surfaces of the cam 98, to reduce puffing of the product out of the pouch. This is accomplished by modifying the shape of the cam 98 to include gradual transitions indicated by the dashed lines 99.

According to important features of the method, the lands are gradually pivoted or rotated outwardly to increase the tension at the top of the pouch. By eliminating the tension at the top of the pouch, the tendency for the pouch to close with a "snap" is minimized, thereby reducing puffing of the product out of the pouch.

The cam 98 is supported by means of spacers 140 on the surface of the table 24 and bolts 142 pass through the cam 98 and spacers 140 to hold the same in fixed relation with the table 24.

Referring again to FIG. 2, it is seen that a filling wheel 144 is supported above the upper end of the shaft 108, on a second shaft 146, which is supported at its upper end on a bracket assembly 148 secured above the surface of the table 24 by means of three upstanding posts 150 (FIG. 1), and at its lower end by a bearing assembly 149 bolted to the shaft 146 by a bolt 147, and rotatable in a recess disposed in the upper end of the hub 110. The shaft 146 is disposed at an angle relative to the shaft 108 to facilitate filling of the pouches by gravity in a manner which will be described. The filling wheel 144 is supported by a bearing assembly including bearings 143 and 145 mounted on the shaft 146 at the upper and lower ends of a hub 151 bolted to the wheel 144, and rotated indirectly by the shaft 108, by means of a universal joint comprising a pair of rollers 146' secured to a bracket 153 attached to the bottom of the wheel 144, the rollers 146' being engaged in notches 152 within the upper portion of the hub 110. As the shaft 108 rotates the sides of the notches 152 bear against the rollers 146', imparting angular momentum to the wheel 144, and the rollers 146' slide up and down in the notches 152 as required to account for the difference in the axis of rotation of the shaft 108 and the shaft 146. One portion of the filling wheel 144 is spaced closest to the carrier wheel 95, and it is at this portion that the filling tubes 154 enter the pouches to deposit the product thereinto.

A plurality of the filling tubes 154 are disposed at spaced locations around the filling wheel 144 and each communicates at its upper end with the interior of a funnel 156 which opens at the upper surface 158 of the filling wheel 144. A rim 160 surrounds the upper surface 158 so that the product which is deposited onto the surface 158 is constrained to remain within the rim 160 until eventually it enters one of the funnels 156 and falls through one of the tubes 154 into a pouch.

As best shown in FIG. 1 a filling funnel 162 is disposed above the wheel 144 and product material loaded into the funnel 162 is deposited at a uniform rate on the upper surface 158 of the wheel 144. As the wheel 144 rotates a scraper blade 164 scrapes the material deposited by the funnel 162 into one or more of the funnels 156, and by the time the wheel 144 has rotated to bring the product material to the end of the scraper blade 164, all of it has fallen into the funnels 156. Because of the uniform rate of depositing the material by means of a funnel 162, and the uniform angular velocity of the wheel 144, each of the funnels 156 receives an identical quantity of material, and this quantity is precisely the quantity desired to be inserted into the open pouches in the filling process. A hook (not shown) overlies the wheel 144, except above the funnel 162, to protect the upper surface 158 from drafts and the like. The position of the hood is indicated in FIG. 1 by the dashed lines 163.

Referring again to FIG. 2, it is seen that the lower side of the wheel 144, which is shown on the left side of FIG. 2 is sufficiently low as to cause the filling tubes 154 to enter into the upper portion of the pouches 71, while the filling tubes 154 are withdrawn from the pouches as they rotate toward the right side of FIG. 2. The location of the funnel 162 and the scraper blade 164 is such that the material to be deposited in the pouches enters the tubes 154 while they are inserted within the pouches. Each of the tubes 154 is, therefore, in operative engagement with the open upper side of a pouch only during the filling process, and are automatically withdrawn therefrom by the rotation of the wheel 144.

A bellows arrangement 166 is connected at its lower end to the upper surface of the wheel 95 and its upper end to the lower surface of the wheel 144, and also to protect the universal joint and bearing arrangement from dust.

Shown in FIG. 3 is a vibrator V. The inclusion of the vibrator is optional. With certain types of material or product, it is envisioned that it would be helpful to use the vibrator for the purpose of enabling the product to be more totally redistributed to the bottom of each pouch.

From the foregoing, it can be seen that the present invention is effective to quickly and positively open each of the pouches, and to settle the product deposited therein as much as possible, to make a compact package. The entire process is carried out continuously with the web 9 moving at constant speed, and there is no need for indexing or other intermittent motion of the apparatus. The filling process is also continuous, with the steps of opening the pouches, inserting the filling tubes, filling the pouches, removing the tubes, rocking the pouches, and sealing the open ends thereof being carried out without hesitation or interruption.

Claims

What is claimed is:

1. A method of forming and filling pouches, comprising the steps of:

forming a continuous train of pouches from a strip of web material, each of said pouches having an upwardly open side adjacent an upper edge of said web,

filling each of said pouches with a predetermined quantity of a product,

placing the upper edge of said web under tension and relieving the lower edge of said web from tension to settle said product within each of said pouches, and

sealing the open side of each said pouch to form a filled and sealed package.

2. The method according to claim 1, wherein said settling step comprises causing said web to traverse an arc with the path of said upper edge having a larger radius of curvature than said lower edge.

3. The method according to claim 1, wherein said settling step comprises the steps of alternately and repeatedly placing said upper edge and said lower edge under tension.

4. The method according to claim 1 where said upper edge is gradually tensioned to gradually close the open side of each of said pouches.

5. In a packaging machine for forming and filling pouches including:

means for forming a continuous train of pouches from a supply of web material, said pouches each having an upwardly opening side adjacent the upper edge of said web,

means for opening the upper side of each said pouch,

means for filling each said pouch with a predetermined quantity of product, and

means for sealing the upper edge of said web to produce filled and sealed packages, the improvement comprising:

means for placing the upper edge of said web under tnesion and relieving the lower edge of said tension after filling, thereby modifying the shape of said pouches after filling to settle the product therein.

6. Apparatus according to claim 5, including means for alternately and repeatedly placing said upper edge and said lower edge under tension.

7. In a packaging machine for forming and filling pouches including:

means for forming a continuous train of pouches from a supply of web material, said pouches each having an upwardly opening side adjacent the upper edge of said web,

means for opening the upper side of each said pouch,

means for filling each said pouch with a predetermined quantity of product, and

means for sealing the upper edge of said web to produce filled and sealed packages, the improvement comprising:

said filling means including a carrier wheel having a plurality of land members projecting radially from said carrier wheel and adapted to engage areas of said web between adjacent pouches during the filling of each said pouch,

means for rotating said carrier wheel, and

means for varying the attitude of said land members as said carrier wheel is rotated to modify the shape of said pouches after filling to settle the product therein.

8. Apparatus according to claim 7, including cam means mounted in fixed relation to the axis of said carrier wheel, cam follower means connected to each of said land members and means for mounting said land members on said carrier wheel whereby the attitude of said land members is controlled by said cam means as said carrier wheel is rotated.

9. Apparatus according to claim 8, wherein said cam means has a cam surface engaged by said cam follower, said surface being shaped to gradually change the attitude of said land members to gradually increase the tension on the upper edge of said web to gradually close said upper side of said pouch.

10. In apparatus for filling pouches formed as a continuous train from a strip of web material, said apparatus including a carrier wheel about which said strip passes during filling, the improvement comprising:

a plurality of generally vertical lands movably mounted in spaced relation around said wheel, said lands being engageable by said strip with said pouches located between adjacent lands,

and means for shifting the attitude of said lands between a first upwardly radially inwardly-inclined position and a second upwardly radially outwardly-inclined position.

11. Apparatus as in claim 10 further comprising:

means pivotally mounting each land to said wheel,

a cam disposed adjacent said wheel,

and a cam follower interconnecting each land and said cam to rock each said land between said positions.

12. Apparatus as in claim 10 further comprising:

means for filling said pouches with a product when said lands are in said first position,

said lands thereafter moving to said second position to reduce the tension on the bottom of each pouch, thereby causing said product to shift to the bottom of said pouch.

13. A method of forming and filling pouches, comprising the steps of:

forming a continuous train of pouches from a strip of web material, each of said pouches being defined by spaced transverse seals and having an upwardly open side adjacent an upper edge of said web,

reducing the distance between the upper ends of adjacent transverse seals to open said pouches,

filling each of said pouches with a predetermined quantity of a product,

thereafter increasing the distance between upper ends of adjacent transverse seals while reducing the distance between lower ends of adjacent transverse seals to settle said product within each of said pouches, and

sealing the open side of each said pouch to form a filled and sealed package.