Packing machine

[57] ABSTRACT

A table type machine for packing goods into contain ers having lids and closing means of the press-button type with complementary container-locking elements located in respectively the container and lid edge portions, comprising an endless conveyor belt for sequentially receiving containers in an open position at an infeed end thereof for filling the containers with the goods, and conveying the filled containers towards a closing station at the outlet end of said conveyor belt with the lids being in a generally closed position. The machine includes a rotor wheel having a plurality of circumferentially spaced, radially extending spoke members being positioned above the endless conveyor belt proximate said closing station, the radially outer free ends of the spoke members following a circular path of movement intersecting the linear movement of the containers on said conveyor belt. A first one of the spoke members, upon the container reaching a predetermined position relative to the rotor wheel is contacted by the container in pushing engagement so as to impart rotation to the rotor wheel and cause the subsequent spoke member to be pivoted downwardly into punching contact with the container-locking element on the lid edge portion so as to bias the latter toward and into locking engagement with the complementary element on the container.

Claims, 6 Drawing Figures

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PATENTED APR 151975

3,877.205

SHEET 1 OF 2

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PATENTED APR 151975

3,877,205

SHEET 2 OF 2

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3,877,205

PACKING MACHINE

The present invention relates to a table type packing machine for packing goods in plastic containers or boxes provided with hinged covers or lids, the lid at the closing being attached to the container by means of complementary press-button-like locking elements provided along the container edge and the lid edge, respectively. Such containers have in more recent years come into broad usage in connection with packing and marketing, among others, of food products, such as tomatoes. fruits, eggs, etc.

A relatively simple packing machine used for packing goods in such containers consists of a packing table including a horizontally extending conveyor belt, at the beginning of which there is positioned a magazine or supply of containers whereby the containers may be fed, one after the other, onto the moving belt. The filling of the containers usually takes place manually while the containers are moving along the belt in an open position. When the containers have been filled upon approaching the outlet end of the conveyor belt, the containers are closed and preferably locked together before further handling and transport.

The closing and the locking of the containers by means of the press-button elements constitute, due to the special characteristics of the containers and the locking element, a relatively cumbersome and time consuming operation.

Containers of this type are usually made by vacuum forming of plastic sheet material or film which is preferably formed of a material such as shock resistant polystyrene or polyvinyl cloride. The container is configurated with partitions or rooms for a certain number of units of the goods, and the push-or press-button elements are provided in that the plastic sheeting material is impressed or formed with complementary male and female configurations along the abutting edge portions of the container and lid, respectively. In the edge portion of the container there is therefore present, par example, a tap-like recess and in the complementary edge portion of the lid there is provided a corresponding taplike protrusion or recess whereby these may be pressed together, if desired, with a snap action. The locking action, as such, will and partly depend upon friction, partly in that the goods in the locking elements during the pressing together action are subjected to elastic deformation. This implies that the press-button elements may not always be easily snapped or pressed together by exerting pressure against the lid and/or the container, since the sheet material in the lid and/or container, particularly outside or beyond the locking elements, frequently will yield and thereby prevent that the locking elements, although in register, come into the desired mutual engagement. When closing and pressing the container parts together, the container and the lid must therefore, to a certain degree, be supported in the vicinity around the locking elements such that sufficiently bias is provided on the overside of the lid edge and the underside of the container edge. If the locking action of the container takes place manually, the operator simultaneously positions, as known, the fingers on the overside and underside of the flange edges of the container as the fingers are pressed towards each other. When continuously packing along a transport belt, such manual locking of the containers becomes however, both time- and work consuming and may easily constitute a bottleneck in the packing process, particularly if the packing concerns containers each having two or more press-buttons.

Furthermore, the goods, usually fragile goods, such as tomatoes, may easily be damaged.

Based on the abovementioned situation, the present invention has its object to provide a relatively simple mechanical device for effecting the automatic closing and locking of such containers subsequent to completion of filling of the containers.

The machine, in accordance with the invention, is of the type comprising an endless conveyor belt means for receiving the containers from a supply thereof, one after the other, effecting advancement of the containers in open position and filling the same with goods, such as tomatoes, and a closing station towards the outlet end of the conveyor belt, the containers being provided with closing means of the press-button type with complementary elements located in the container and the lid edge portions, respectively, and the machine is characterized in that above the final part of the conveyor belt, there is pivotally supported a rotor wheel which is provided with a plurality of circumferentially spaced radially extending spoke members, the other parts of which follow a circle extending down into the path of movement of the containers advanced on the belt, effecting that when each separate container reaches said rotor wheel, the container pushes a first spoke on the rotor wheel forwardly whereby the subsequent spoke on the wheel is pivoted downwardly into contact with the lid on the container into register with the press-button means and effecting compression and mutual locking-together of the complementary pressbutton means on the container and the lid. respectively.

The spoke members on the rotor wheel will thus, in alternating fashion function, as pushing rods and as punching rods for the together-pressing of the pressbutton elements on the container. The dimensioning of the rotor wheel and the spokes etc. and the mutual location of the parts must obviously be accurately adapted to the shape and size of the containers in question. If the container has only one press-button locking means the rotor wheel is only provided with one set of circumferentially arranged spokes. If, however, the container has two or several press-buttons, the rotor wheel must be provided with a corresponding number of laterally arranged sets of rods.

Through the invention there is obtained a very effective means for locking the containers. Because the device is very simple, its operation and use is very dependable. The movement of the rotor wheel are — as will be understood — provided by the motor driving the transport belt via the containers, since the containers are utilized to position the containers and the operation of the locking means. Separate drive means or operation of the rotor wheel and coordination of the moving parts are rendered superfluous.

In a preferred embodiment of the invention, the containers are advanced on the belt with the hinged lid ahead or upstream in order to facilitate the closing action. The rotor wheel is suitably provided with two types of spokes which in alternate fashion constitute sensor spokes and punching spokes, and the punching rods are preferably somewhat longer than the sensor rods which hit against the side of the lid. Each of the punching rods is imparted such length that it exactly extends down into the press-button recess in the upper

3,877,205 edge of the lid when this part of the container is positioned vertically below the rod at the passage of the container, so as to ensure the complete togetherbringing of the locking elements. The containers are seated against spaced cleats attached to the belt, and it constitutes a feature of the invention that those cleats are imparted such configuration that a part of each cleat surrounds the locking elements on the underside of the container and thereby forms the desired biasing means which can cooperate with the punching rod on the rotor wheel.

A further feature of the device in accordance with the invention consists in that above the part of the conveyor belt ahead of the rotor wheel is provided with a device effecting the preliminary closing action of the lid onto the container.

The device in accordance with the invention will now be described in detail with reference to the enclosed drawings which are illustrative of an embodiment for a packing machine provided with the device in accordance with the invention and wherein:

FIG. 1 shows a schematic lateral view of a packing machine constructed in accordance with the invention.

FIG. 2 illustrates a plan view of the machine shown in FIG. 1.

FIG. 3 illustrates a detail lateral view which in an enlarged scale, shows the device in accordnce with the invention.

FIGS. 4 and 5 are detail lateral views which, in an enlarged scale, illustrate two stages during the operation of the machine respectively, and

FIG. 6 is a plan view which in detail shows a modified embodiment of a device in accordance with the invention.

In FIGS. 1, 2 and 3 the frame of the machine is given the reference number 2, and which comprises a table 4 having legs 6 and 8. In the table there is mounted an endless conveyor belt 10 which runs over rollers 12,14 located at each end of the table, the belt being driven by an electric motor 16 through a strap 18. The upper run of the belt is positioned flush with the table and is framed by side edges 15, 17 so as to form a chute or trough 19 along the table. At the infeed end of the table there is mounted a feeding device 20 for a stacked supply 22 of containers 23 so that these — one after the other — may be fed down onto the belt 10 in an open position, slated against pushing cleats 24 attached to the belt.

Towards the outlet end of the table, attached on each side of the table is an upright post 26, 28 in which there is journalled a transverse shaft 30 for a rotor wheel 32 provided with a plurality of circumferentially spaced spoke members 34,36, etc. which, as best appears from FIG. 3, extend down into the feeding path of the containers on the belt. Above the feeding path, in the vicinity at the rotor wheel, there is furthermore provided a horizontally arranged cover 40 having a backwardly extending, upwardly sloped tray portion 42. The cover 40 and the tray 42 each have an opening slit along the center section thereof in order to pass therethrough the spokes 34, 36 etc. on the rotor wheel. On the table before the wheel there are furthermore positioned two posts 46,48 between which there is pivotally journalled a forwardly directed yoke 50 having downwardly directed hook means 52.

The further construction of the machine and the particular features essential for the invention will appear more clearly from the following description of its operation, with special reference to the detail in FIGS. 4, 5 and 6.

As previously mentioned, the containers 23 are being fed — one after the other — in a flat opened position down onto the belt 10 from the supply magazine 20 so as to rest against a pushing cleat 24. During the advancing movement on the belt along the table, the containers are being filled with goods, for instance tomatoes, by operators, standing along the sides of the table. When the containers — with the lids directed forwardly — arrive at the yoke 50, which normally rests loosely on the table, the hook means 52 come into engagement with the lid 23', as shown in FIG. 3, having the consequence that the lid, during the advancement of the container, is turned up and into a closed position as indicated by the number 23 in FIG. 3. In this position the container arrives at the tray 42 on the cover 40 whereby the lid is pressed downwards against the upper edge portion of the container, and thereafter the container with its closed lid is moved forwardly below the cover 40. In this position the container hits a spoke 34 on the rotor wheel — as shown with the arrow A — so that the wheel is thereby pushed forwardly by the container. When the container 23 comes into the position illustrated in the detail view of FIG. 4, the spoke 34 has been pushed further forwardly, having the consequence that the next spoke on the wheel designated 36— a socalled punching spoke — has been pivoted down behind the container and has arrived exactly in position against the press-button element 60 on the container. During the further advancement of the container on the belt, the punching spoke 36 is pivoted further downwardly and is thereby presses the pressbutton elements progressively together into the completely assembled position as shown in FIG. 5, wherein the punching spoke 36 stands vertically. As appears from FIG. 5, the cleat 24 which is attached to the belt 10 is configurated so that the cleat is adapted to the contour of the container and, to a large extent, forms a biasing surface below the edge or flange portion of the container around the press-button elements with the exception of an open zone along a forwardly open groove 62, as best shown in FIG. 6. The cleat 24 therefore serves as an anvil for the punching spoke 36 and provides a bias securing the complete interlocking of the complementary press-button elements on the container and the lid, respectively. During the further advancement of the container, the punching spoke leaves the container while the rotor wheel is turned a further distance until the punching spoke 36 also leaves the press-button element recess and, at this moment, the rotor wheel discontinues rotation. In this position the rotor wheel has arrived at a position in which the next container hits the spoke 37 (a pushing spoke), whereby the process is repeated. In order to assure that the rotor wheel only rotates when the spokes or rods are in contact with the container, a friction coupling 64 is suitably located in connection with the bearings of the rotor wheel.

As will be understood, the configuration of the rotor wheel, the thickness of the spokes or rods and the length of same, and the dimensioning and positioning of the various parts must be exactly calibrated to the type of container which is to be packed or handled in the machine. An essential point is that the distance between the spokes on the rotor wheel is adapted and ex3,877,205 actly calibrated so that the pushing rod provides for that the punching spoke hitting into the press-button elements of the container. In the shown embodiment there is illustrated a container for four tomatoes and it is provided with a single press-button lock. If the machine is to be utilized for packing containers having, for instance, two press-button locks along one lateral edge, the rotor wheel must be provided with two axially or laterally spaced sets with punching rods so that there is obtained simultaneous locking of the two press-button locks on the container, provided the locks are positioned transverse to the direction of movement. The spokes on the rotor wheel must always be adapted to the container in question and can otherwise be configurated in various fashions. It is, however, usually sufficient to provide one set of pushing rods which, for instance, are suitably positioned along a circle between the sets of punching rods or spokes. In the embodiment shown in the Figures it can, in some cases, be practical to arrange the punching rods and pushing rods, respectively, laterally displaced on the rotor wheel such as indicated in FIG. 6, for instance in order that the pushing rods 34 always will touch the highest parts of the lids as illustrated best in FIG. 4. The pushing spokes 34 may also be configurated as laterally extended plate-shaped elements instead of individual spokes, and such spokes may be built together in couples so that one pushing spoke and one puching spoke together are configurated as a fork, the stem on which is attached to the hub of the rotor wheel.

Other embodiments may be realized within the scope of the invention such as defined in the following claims. In regard to the hinged connection between the container and the lid respectively, it will be understood that any hinged connection may be used. The hinge can thus be formed integrally and in one piece with the container and the lid respectively, or separate hinge elements, such as pivot pins, can be used. Furthermore the “hinge” can be realized by any knid of releasable hinge means, such as press-button means, which are assembled prior to the handling in the packing machine, as described.