METHOD AND APPARATUS FOR APPLYING GLUE FOR SEALINGLY MOUNTING OF LIDS IN PACKAGES AND CONTAINER TUBES

Abstract: Method and apparatus for applying glue on separate lids (6) and sealingly introducing said lids (6) in containers (18), especially by means of a fully automatic apparatus comprising a supplier (1) for lids (6) or lid panels, a rotor (8) or carousel useful for multi-­ stage handling of lids (6), or lid panels or lid frames having a reclosing lid rotatably connected thereto, and received from the lid supplier (1), and a supplier (4) of packages or containers tubes (18) co-operating with said rotor (8), and in which the lid handling rotor (8) comprises one or more lid catchers (10-13) which can be expelled from and be retracted into the rotor (8) for catching a lid (6) from the lid supplier (1), and for pressing lids (8) into the open end of a container presented by the container supplier (4), and which can also rotate about a shaft which is radial in relation to the rotor (8), whereby glue or an equivalent adhering substance is applied to the edge of the lid or the lid panel by means of a stationary glue application means (3).

Description: The present invention generally relates to a method and an apparatus for applying glue to separate lids, in the following generally referred to as lid elements, and for mounting of said separate lid elements in packages or containers, and the invention is more particularly directed to a fully-automatic such method and apparatus for sealingly mounting of lid elements in packages and container tubes. In this connection the word "lid element" is used for all kinds of lids, end panels and container ends which are applied and secured inside a package or a container, generally a tubular container. The "lid element" is for instance a lid, and end panel or a container end of plastic, cardboard or metal. The invention is especially suited for, and solves special problems in, handling of such reclosable lids having a annular lid rim adapted to be secured at the interior of a container or a container tube, and a reclosable lid, which is rotatably connected to the lid frame, generally by means of a hinge, and which is preferably sealingly connectable inside said lid frame. When mounting of lids at the ends of tubular container is has so far been usual to apply glue or so called hot-melt to the inner edge of the lid frame or the end closure and to then press the lid frame or the end closure to a position inside the container tube. An apparatus for executing the method according to the invention is known, which apparatus comprises a conveyor for lid elements, a rotor or carousel for a several-stage handling of lid elements having reclosing lid elements rotatably thereto, and received from the lid element conveyor, and a co-operating feeder of packages or container tubes. There has, however, been a special problem in machine-handling of reclosable lids of the type comprising a lid frame and a reclosable lid which is hinge connected to said lid frame, since it may happen that the lid frame and the lid are not completely pressed together, or that there is a little space between the lid frame and the lid.If, in such case, the glue is applied by means of a glue spray applicator or a similar means it may happen that the glue ends up outside the edges of the frame to become attached to the container, and that the frame, as a consequence, does not stick sufficiently well to the container tube, and that leakages appear between the lid frame and the container tube and thereby also between the lid and the container tube. The present invention intends to solve the problems and lacks in previously known methods and apparatus for applying glue to the edges of a lid element and to fully-automatically mount the lid element inside a container, especially a tubular container, whereby it is foreseen that the glue is applied evenly and completely round the said edge of the lid, the lid frame or the end panel, and so that a reclosable lid can not be separated from the lid frame or form a clacking space with respect to the lid frame after the bead of glue has been applied on the lid frame edge. The patent EP-A-167.645 discloses a method or pressing a lid into a container, but, contrary to the present invention, the containers themselves are applied to the rotating star wheel rather than the lid elements. Also, the patent does not discuss the problems of applying glue to the lid elements. The patent EP-A-113.703 also discloses a method of applying lid elements to containers, but in this case, contrary to the present invention, the lid elements are applied exteriorly of the container, and the glue of the lid elements are applied in a non rotary mode inside the lid elements. In the method of the invention several lid elements are supplied from a lid element flute to a lid handling rotor or carousel comprising two, or preferably three or more, lid element catchers, a lid element catcher is extended away from the rotor or carousel when being in a position right in front of the lid element flute, and the lid element catcher picks up and holds a lid element, the rotor is rotated and the lid element catcher is set in a predetermined position right in front of a glue application means, the lid element catcher is rotated a complete turn or more by a shaft which is radial in relation to the rotor, while a stream of glue is sprayed onto the outer edges of the lid element, the rotor is rotated another distance until the lid element catcher takes a position right in front of a prepared container, the lid element catcher in this position is extended and presses the lid element into an open end of the container, and the lid element catcher returns to its retracted position and a new operation cycle starts. The apparatus for carrying out said method is mainly characterized in that the lid element handling rotor comprises two or more lid element catchers which are attached to a rotatable shaft which is radial in relation to the rotor, said shaft being rotated while glue or an equivalent adhering substance is applied to the outer edge of the lid element, said glue being applied by stationary glue application means. Further advantages of the invention will be evident from the following detailed description in which reference will be made to the accompanying drawings. In the drawings figure 1 shows a first embodiment of an apparatus according to the invention. Figure 2 shows a commonly used reclosable lid comprising a lid frame and a reclosable lid, in which the lid is shown slightly opened from the lid frame. Figure 3 is a more detailed but fragmentary view of an alternative embodiment of the invention in a stage just preceding the application of glue to the lid edge, and figure 4 shows the next stage of the method, whereby glue is applied. Figures 5 and 6 show, like in figures 3 and 4, a further alternative embodiment of the invention. The embodiments according to figures 3-6 are especially suited for handling of a reclosing means comprising a lid and a lid frame of the type disclosed in figure 2. The apparatus shown in figure 1 generally comprises a means 1 for continuously supplying lids or end panels, a means 2 for handling of said lids or end panels, a glue application means 3 and a means 4 for supplying packages or containers in which lids or end panels are to be introduced. The lid supply means 1 comprises an obliquely extending lid flute 5, in which the lids 6 are conveyed lying upside down, that is with the part thereof adapted to be introduced in the container facing upwardly. The lid flute preferably can be formed with a means (not illustrated) for preheating the lid, so that, at a later stage, the hot glue which is applied to the lid does not become cooled before the lid is introduced in the container. At the end of the lid flute 5 there is a diagrammatically indicated apparatus 7, which is known per se, and which is intended to turn the last lid of the lid flute down to a horizontal position, whereby it can be seized by a lid catcher of the lid handling means 2. The lid handling means 2 comprises a rotor 8, which rotates about a stationary shaft 9, and which comprises at least two, or preferably at least three, or still more preferably four lid catchers 10, 11, 12 and 13, three catchers 10, 11 and 12 of which are shown in active positions, whereas the fourth catcher 13 is shown in an inactive position. All lid catchers are both reciprocatable in and out as indicated with the arrow 14 and rotatable about a radial shaft as indicated with the arrow 15. The lid catchers also are formed with some type of means for seizing a lid, for instance a couple of suction cups 16. The extension and the retraction respectively of the lid catchers may be made positively, for instance by means of (not illustrated) cams, and the lid catchers preferably are spring biassed in the direction towards retraction. The extension and the retraction of the lid catchers also can be accomplished by a pneumatical guide means or in corresponding way. The lid catchers 10 and 12 are illustrated extended but non-rotating, the lid catcher 11 is shown retracted but rotating following the arrow 15, and the lid catcher 13 is shown retracted and non-rotating. It is possible to provide several lid catchers mounted aside of and adjacent each other for multiplying the function when using the apparatus in connection to multiple packaging machines. The container feeder 4 can be of any known type, for instance a conveyor 17 which feeds packages 18 to a specific position, determined for instance by means of stop bars 19, and in which position a lid or an end panel 6 can be pressed down in the container and can be glue connected therein. The illustrated apparatus operates as follows: Several lids 6 are continuously supplied by the lid flute 5, and the last lid in the flute 5 is turned down to a hosizontal position by the the down-turning-means 7, in which position it can be seized by the lid catcher 10 which is present in this position. Concurrently with rotating said lid catcher 10 into the illustrated position it is extended by (not illustrated) cams; the suction cups 16 are connected to vacuum; and the lid which is turned down is seized by the suction cups 16 with the side thereof to become the outside of the lid; the lid catcher is retracted as indicated with the dotted lines in figure 1; and the rotor 8 is rotated, in this case 90° in the clockwise direction to enter the position marked with the lid catcher 11. At the same time as the lid catcher 10 is rotated to the position marked by the lid catcher 11 a new lid catcher is moved to the collection position, position 10; it is extended; and it seizes a new lid from the lid flute 5. In the second position the lid catcher 11 with its lid should be in an exact position in relation to the glue applicator 3, namely in a position in which the edges of the lid frame or the end panel is located exactly in front of a glue pistol 20; the lid catcher 11 starts rotating about its axial shaft which extends radially in relation to the shaft 9 of the rotor 8; and in the same moment the glue pistol 20 is activated so as to spray a stream 21 of glue onto the frame edge or the panel edge. By the rotation of the lid the glue is spread evenly round the entire frame or panel edge. Normally it is sufficient that the lid is rotated exactly one turn, but on special occasions it is, of course, possible to have the lid rotate several turns, thereby eventually also moving the stream 21 of glue slightly aside so as to provide several beads of glue aside of each other, which beads form, in common, a wide bead of glue. After the lid edge is covered with glue the lid catcher 11 is retracted ; and the rotor 8 is rotated another 90° so that the lid catcher 11 with the lid which is now supplied with glue enters the position marked with the lid catcher 12. In some cases, which are to be described more closely in the following, it is also possible, in the position "11", to extend the lid catcher an exactly predetermined distance so as to take a position exactly in front of the glue applicator 3. This is advantageous in eliminating drops or overflow of glue to hit the lids or the machine parts included in the apparatus. At the same time as the lid, now supplied with glue, and seized by the lid catcher 11, is rotated to the position for introduction of the lid in a container 18, a new lid catcher is rotated up to the position "10", and a lid which has previously been seized is rotated to the glue application position "11". The lid catcher which is in this mounting position marked with numeral "12", and which is still holding the lid, is in this position exactly above the opening of a package 18 or a container tube; the lid catcher 12 is now extended, whereby the lid is pressed down in the open end of the container for becoming glue connected thereto. When using complete end panels having fold up edges said edges are glued onto the inside of the container; when using reclosable lid means having a lid frame and a reclosable lid the lid frame of said means is glue connected to the container, whereas the lid is, in turn, secured inside the lid frame. The suction cups 16 of the catcher 12 are released from vacuum, whereby the lid is let free; the catcher is retracted; and the rotor 8 is once more rotated over 90°, whereby the catcher, which is in this position marked with 13, takes an inactive position until it has been rotated still another 90° up to the position for seizing a new lid, whereby an entire operation cycle completed. In some cases it may happen that the lid is not kept quite plainly by the suction cups 16 and that the glue strem 21 may fall outside the lid edge. When handling a reclosing means comprising a lid frame and a reclosable lid it also may happen that the lid opens more or less from the lid frame while handling said reclosing means, or that there is a slight space between the frame and the lid. Such a case is diagrammatically illustrated in figure 2. The suction cups 16 hold the reclosing lid, but in this case the frame has become slightly released from the lid and has folded out, so that the glue stream will irrevocably partly fall outside the intended glue edge 22. For eliminating said problem the apparatus of figures 3 and 4 is formed with an outer pad or holder plate 23 which with respect to shape and size fits the bottom end of the lid panel or the bottom end of the lid frame. At the same time the lid catchers - in the illustrated case only the lid catcher 11′ - are formed so that the suction cups 16′ and also the catcher body is spring biassed 24 inside a slide 25. Thus, figure 3 shows a lid which is held by the suction cups 16′ a slight distance in front of the catcher body 11′. Figure 4 correspondingly shows how the holder plate 23 compresses the lid and the frame and presses said parts into contact with the catcher body 11′ and whereby the glue stream will fall exactly on the intended place of the lid frame or the lid panel. In the slide there is a diagrammatically indicated tooth coupling which, in the position when the lod catcher 11′ is extended, locks the lid catcher 11′ in relation to the slide 25 thereby preventing a rotation of the lid catcher 11′ about an imaginary axis of the lid catcher 11′ and of the slide 25 (figure 3), and which, in the position when the catcher 11′ is pressed towards the rotor 8, releases the tooth coupling thereby making a rotation of the lid catcher with lid or the end panel possible, which rotation is necessary for applying glue on the lid or the lid frame. The apparatus of figures 5 and 6 differs from the apparatus shown in figures 3 and 4 in that the catcher body 11″ is formed for being extended to two different positions, namely a first position for collecting lids (station 10) and for pressing lids down into the open end of the container (station 12), and a second position, in which the lid catcher 11″ is extended so as to press the lid against the holder plate 23, in which the lid is rotated and glue is sprayed onto the edge of the lid panel or the lid frame. The apparatus of figures 5 and 6 further differs from the previously shown embodiment in that it is formed with a glue splash cover 26 which follows the movements of the lid catcher 11″ as indicated with the dotted lines 27, and which in all positions except for the spray position for the glue pistol 20 covers the spray nozzle so that no glue can drop down on any part of the apparatus. Further, this last mentioned apparatus is equipped with a photo cell sensor 28 which is intended to sense that a glue stream is sprayed onto the lid. For the purpose the photo cell is coupled to the means for rotating the lid catcher 11″ so as to observe that glue has been applied during an entire turn, or in some cases several turns, of the lid catcher. If there is no glue stream the machine is stopped.

Claims: A method for applying glue to separate lid elements and introducing said lid elements in packages or containers, especially a fully automatic method for such application of sealing lid elements in packages or container tubes, characterized in that several lid elements (6) are supplied from a lid element flute (5) to a lid handling rotor (8) or carousel comprising at least two lid element catchers (10-13), a lid element catcher (10) is extended away from the rotor (8) or carousel when being in a position right in front of the lid element flute (5), and the lid element catcher picks up and holds a lid element (6), the rotor (8) is rotated and the lid element catcher (11) is set in a predetermined position right in front of a glue application means (3), the lid element catcher (11) is rotated a complete turn or more by a shaft which is radial in relation to the rotor (8), while a stream (21) of glue is sprayed onto the outer edges of the lid element (6), the rotor (8) is rotated another distance until the lid element catcher takes a position right in front of a prepared container (18), the lid element catcher in this position (12) is extended and presses the lid element into an open end of the container (18), and the lid element catcher (12) returns to its retracted position and a new operation cycle starts. Method according to claim 1, characterized in that a holder plate (23) presses the lid element (6) against the lid element catcher (11) before the glue application is started and while glue is applied round the edges of the lid element. Apparatus for executing the method according to claim 1 or 2 and comprising a conveyor (1) for lid elements (6), a rotor (8) or carousel for a several-stage handling of lid elements (6) having reclosing lid elements rotatably thereto, and received from the lid element conveyor (1), and a co-operating feeder (4) of packages or container tubes (18), characterized in that the lid element handling rotor (8) comprises two or more lid element catchers (10-13) which are attached to a rotatable shaft which is radial in relation to the rotor (8), said shaft being rotated while glue or an equivalent adhering substance is applied to the outer edge of the lid element (6), said glue being applied by stationary glue application means (3). Apparatus according to claim 3, characterized in that the lid element handling rotor (8) is formed with at least three lid element catchers (10-13) which are all active and can take at least three different angular positions, and each of said lid catchers, in one position (10) of the rotor (8) picks up a lid element (6) from the lid element conveyor (1), in a second position (11) of which the lid element (6) is rotated while glue (21) is applied, and in a third position (12) of which the lid element (6) is pressed down in the container (18). Apparatus according to claim 3 or 4, characterized in that the glue application means (3) is a glue spraying apparatus (20) which is stationary mounted in a position for applying a stream (21) of glue onto an exactly determined place at the edge of the lid element while said lid element is rotated one turn. Apparatus according to claim 3, 4 or 5, characterized in that a splash cover (26) having a through bore is mounted between the glue application apparatus (3) and the lid element while in position for the application of glue thereto, which splash cover (26) is preferably movably mounted, and the said movement of which is coupled to the extension movement of the corresponding lid element catcher (11), whereby said splash cover (26) prevents drops and splashes of glue to hit any of the part of the apparatus in any positions except when the lid element is in the glue application position. Apparatus according to any of claims 3-6, characterized in that it comprises a holder plate (23) which is mounted adjacent the glue application apparatus, and which is adapted to press the lid element (6) against the lid element catcher (11) so as to intimately compress said parts during the glue application process. Apparatus according to claim 7, characterized in that, in the glue application position of the rotor (8), the holder plate (23) is axially movable whereas the lid element catcher (11′) is axially non-movable, or the holder plate (23) is non-movable whereas the lid element catcher (11″) is axially movable in the direction towards the holder plate (23). Apparatus according to claim 7 or 8, characterized in that the lid element catcher (11) is formed with suction cups (16) or similar means for holding a lid element (6), and in that said suction cups are at least slightly spring actuated so that the lid element comes into a butt contact with the lid element catcher (11′; 11″) only when acted upon by the holder plate (23). Apparatus according to claim 7, 8 or 9, characterized in that the entire lid element catcher (11′; 11″) is axially resiliently (24) received in a slide (25) of the rotor (8), and in that the lid element catcher is adapted to be kept in a non-rotatable position by an inner tooth coupling (25) when it is in its position extended by the spring means (24), whereas said tooth coupling (25) releases the lid element catcher (11′; 11″) for rotation about an imaginary shaft of the slide and the lid element catcher when the lid catcher is pressed towards the rotor (8) against the action of the spring means (24).

Inventors: BIRATH BJAERN, Birath Bjärn
Applicants: AKERLUND & RAUSING LICENS AKTIEBOLAG
Application year: 1989
Main classification: B31B17
IPC codes: B65B51, B31B17, C09J5, B31B1