EP0164585B1 - Machine producing folded boxes from blanks - Google Patents

Abstract

1. Machine for producing folded boxes from blanks, in which a blank is withdrawn in each case from the bottom of an exchangeable magazine (4), is laid on two mutually parallel guiding rails (2, 3), is conveyed by means of a conveying system (21) to an exchangeable shaping system (6) comprising an end stop for completion of the folded box, wherein a bonding substance is applied at predetermined points of the precut blank by means of an applicator device (13) and in which the shaping system (6) comprises a plunger (7) as well as a shaft (12) situated thereunder and open at the top and bottom, characterized in that the two guiding rails (2, 3) are adjustable in their mutual horizontal spacing, that the magazine (4) has two downwardly extending and mutually opposite lateral fixed stops (20) against which the displaceable guiding rails may be brought into abutment, that each guiding rail (2, 3) in a manner known per se carries at least one applicator head (13) adjustable in the longitudinal direction of the rails and vertically thereto, and that there is provided for each applicator head a switch (33) for placing the applicator head in operation, which is longitudinally adjustable, and operated by an entraining finger (23) of the return leg of an endless conveying system (21).

Description

The invention relates to a machine for producing folding boxes (so-called trays) from blanks, in each of which a blank is removed from an interchangeable magazine at the bottom, placed on two parallel guide rails and conveyed by means of a conveying device to an interchangeable shaping device with an end stop for finishing the folding box , wherein a connector substance is applied at predetermined points of the blank by means of an application device, and wherein the shaping device consists of a stamp and an underneath, open at the top and bottom.

In a known machine of this type, the application heads operated with glue are arranged in the removal area of the magazine, a corresponding number of application heads being provided with regard to the areas of the respective blank to be provided with glue. By means of a swivel device, the removed and glued blank is conveyed to the molding device, where it has to be centered over the shaft. For the respective alignment of the application heads and the centering of the blank above the shaft, corresponding holding and adjusting or centering devices, provided with spindles and cranks, are provided, which are complex to set up and cumbersome and time-consuming to use if a different tray blank size in the machine; should be processed, since in this case both the magazine and the molding device must be replaced. Furthermore, the application of glue to the predetermined areas of the blank is inaccurate, since the application heads are relatively far away from these areas and a fairly large spraying distance has to be covered as a result, which also results in increased glue consumption.

DE-A-18 04420 describes another machine of the type in question, in which two mutually parallel and fixed guide rail parts extend from the blank magazine to a folding shaft, where they combine to form a plate, the opening of which simultaneously opens the opening of the Folding shaft forms. A conveyor element moves back and forth between the two rail parts in order to promote the cutting from the magazine to the folding shaft. Above the folding shaft is a combined tool which is mounted independently of the rail parts and which is a gluing unit and a form stamp at the same time. A disadvantage of this machine is that when changing the blank, in addition to the magazine and the folding shaft, the guide rail parts and inevitably also the gluing unit must be replaced, since the latter in particular is combined with the form stamp. The replacement of the guide rail parts is only possible through a complicated construction, which makes the machine more expensive to manufacture and its operation is time-consuming and cumbersome. In addition, it is not possible to only change the gluing unit if certain application heads are desired by the user of the machine due to certain connector substances for the side walls of the tray blanks.

The object of the invention is to provide a machine of the type mentioned in the introduction, which, in addition to structurally simplifying the adjustability of the guide rails and the application heads, as well as being more cost-effective to manufacture, can be converted more quickly and in a more user-friendly manner to other tray cut sizes, in which the application heads can be replaced alone and in which the connector substance can be applied precisely.

The solution is based on the introductory machine and is characterized in that the two guide rails can be adjusted to one another in the horizontal state, that the magazine has two lateral, downwardly extending and opposite, fixed stops, against which the adjustable guide rails come to rest Can be brought that each guide rail carries in a conventional manner at least one applicator head adjustable in the longitudinal and vertical direction of the rail and that each applicator head is assigned a length-adjustable switch actuated by a driver finger of the return run of an endless conveyor for operating the applicator head.

This solution eliminates the complex spindle and crank adjustment devices as well as the other additional adjustment means in order to be able to readjust the guide rails, the application heads and the centering of the new blank in the molding device when the blank is changed. Instead, after changing the magazine and the shaping device, only the two continuous guide rails need to be adjusted in the lateral direction, which are brought to bear against the stops now attached to the magazine. This also results in a lateral positioning for the blank in the shaping device, so that the blank in question is finally centered in cooperation with the end stop of the new shaft. Since the application heads are already firmly connected to the guide rails, they are automatically adjusted in the lateral direction, with no height adjustment being necessary in many cases. Furthermore, there is now more space available for attaching application heads of different sizes, since these can be conveniently provided between the magazine and the molding device. In addition, the Application heads are now set at a precise distance from the blank moving beneath them and can be controlled precisely in a simple manner so that a precise connector application, preferably glue, can be carried out, it also being possible to selectively apply a spot or stain or to provide a stroke order. Finally, each guide rail only needs to be provided with an application head, in order to be able to provide all of the required locations on the associated side of the blank with glue.

• Figur 1 einen Längsschnitt durch das Ausführungsbeispiel,
• Figur 2 einen Faltschachtelzuschnitt in Aufsicht,
• Figur 3 einen Schnitt nach der Linie A-A in Figur 1,
• Figur 4 eine Aufsicht auf die Darstellung nach Figur 3,
• Fig. 5,6,7 Querschnitte nach den Linien B-B, C-C bzw. D-D in Figur 1.

The invention is explained below with reference to an embodiment shown in the accompanying drawings. Show it:

• FIG. 1 shows a longitudinal section through the exemplary embodiment,
• FIG. 2 is a top view of a folding box blank,
• FIG. 3 shows a section along the line AA in FIG. 1,
• FIG. 4 shows a top view of the illustration according to FIG. 3,
• Fig. 5,6,7 cross sections along the lines BB, CC and DD in Figure 1.

According to Figure 1, the machine consists of the usual, not explained frame 1, which has two mutually parallel and horizontally extending guide rails 2 and 3 and further above one end region of the guide rails with a magazine 4 for receiving a folding box blank 5 and in the other End region of the guide rails is provided with a shaping device 6. The shaping device consists of a punch 7 located just above the guide rails 2, 3 in the rest position, which is attached to the lower end of a vertical support 10 guided by pairs of rollers 8 and 9 and can be moved in the vertical direction by means of a pressure medium cylinder 11 acting on the support 10, and from one below the stamp 7 and aligned on this, as well as open at the top and bottom 12. Between the magazine 4 and the forming device 6, sufficient space is provided in the horizontal direction to be able to attach applicators 13 to the guide rails 2 and 3, so that the Application heads are easily accessible and can be adjusted in a wide range in the horizontal direction, it also being possible to provide a plurality of application heads 13 on a guide rail, which depends on the type of folding box blanks to be processed. The or each application head 13 of a guide rail 2 or 3 is designed to be adjustable in the vertical direction in a manner known per se.

As can be seen more clearly from FIGS. 3 and 4, the guide rails 2 and 3 have an L-shaped cross section and are arranged such that one leg of the rails points upwards, while the other two legs run horizontally, facing each other . Thus, a blank 14, which can be clearly seen in FIG. 2 and is removed from the stack 5 of the magazine 4 by means of a conventional suction gripper device 15a, can be placed on the guide rails and by means of a conveyor device 15 arranged below and between the guide rails from the area of the magazine 4 be promoted to the molding device 6. Here, the blank 14 is passed underneath the application heads 13 and provided with a connector substance, as will be explained.

As can be clearly seen from FIGS. 3, 4 and 7, the guide rails 2 and 3 are fastened to transverse twin bars 16 so as to be adjustable transversely to their longitudinal direction. The twin spars each consist of two parallel rods 16 a, b, which form a slot 17 between them (FIG. 4), through which struts 18 connected to the guide rails 2 and 3 protrude upwards, to which conventional, hand-operated clamping members 19 engage. The guide rails can thus be adjusted at a horizontal distance from one another and can be locked by means of the clamping members 19.

As FIGS. 1 and 6 show, the magazine 4 is provided with two fixed, opposite, lower and arm-shaped stops 20 which extend so far down that a guide rail can come to bear against such a stop on the inside. As a result, the guide rails can be easily adjusted to a newly inserted magazine 4, so that the blank 14 removed at the bottom is readily oriented laterally when it has been placed on the guide rails 2, 3.

The conveyor 15 consists of a conventional endless conveyor 21, the z. B. may have a rocker arm drive chain 22 which is provided with drive fingers 23 with which the blank 14 is conveyed along the guide rails 2, 3. The conveyor also consists of a sliding device 24 adjoining the endless conveyor 21, which takes over the blank 14 from the conveyor 21 and conveys it further into the end position in the shaping device 6. The sliding device has a sliding arm 25 which is resilient in the vertical direction and has a sliding element 26 which comes to rest against the blank 14 to be conveyed further. In the starting position of the sliding arm 25, it bears against an upper guide 27 which keeps the blank 14 pressed down when it runs over the sliding arm 25.

The sliding arm 25 is fastened to a reversible drive cylinder 28, at the front end of which a stop-actuated, conventional reversing element 29 is provided. This reversing element 29 comes to rest against a stop 30 when the blank 14 in the shaping device 6 has reached its end position. Then the drive cylinder 2. moves into its Starting position (Figure 1) back.

As has already been described, the shaft 12 of the molding device 6 can be replaced. For this purpose, each shaft 12 is connected to a frame 31, which in turn is attached to the frame of the machine. This enables the shaft 12 to be replaced quickly. In a further development, the rear region of the shaft 12 in the conveying direction is provided with a fixed end stop 32 which projects into the region between the two guide rails 2 and 3, as can best be seen from FIG. This end stop defines the end position of the blank 14 conveyed into the shaping device 6, as seen in FIG. 1, as shown in FIG. The punch 7 of the shaping device 6 aligned with the shaft 12 can now be moved downwards in order to press the blank 14 into the shaft 12 and thereby form the final shape of the blank 14 into a finished folding box.

A plurality of electrical switching elements 33 are also provided on the frame 1 of the machine in the area of the return run of the endless conveyor 21, each of which is assigned to an application head 13 and controls their operation. The control takes place in such a way that the driver fingers 23 of the driver chain 22 run past the switching elements 33 and interrupt or reflect a working beam of the elements, whereby the operation of the application heads is switched on or ended. The switching elements 23 thus preferably consist of conventional transmitting and receiving elements. These switching elements are fastened to arms 34 which, on the other hand, are arranged so as to be adjustable in the longitudinal direction of the return run of the endless conveyor chain 22 and can be fixed by means of known clamping elements 35.

A supplementary functional description follows below.

It is assumed that a blank according to FIG. 2 is to be formed into a folding box, the folding box that is created being referred to as a so-called tray. However, it should be noted that such blanks can also be processed in the machine described above, which have a lid as a finished folding box. The folding boxes are generally made of cardboard or pate material.

The blank 14 deposited on the guide rails is conveyed in the direction of the shaping device 6 by means of the conveying device 15. As soon as the blank passes under the application heads 13, a conventional sequential circuit, which is controlled by the switching elements 33, causes the blank 14 to be stopped and / or the application heads 13 to be put into operation. In the case in which a spot or stain application is to be carried out, as is indicated in FIG. 2, the blank 14 is stopped and the application taps 13 are operated briefly so that an application of a binding substance, which can consist of glue or an adhesive, is carried out , but preferably consists of hot glue, can be made on the corresponding tab parts of the blank. This can be done in such a way that the blank 14 is moved discontinuously in order to be able to carry out the point application at the required points. If several application heads are used in succession, the blank 14 is stopped only once, so that all point orders are carried out simultaneously. It is readily understandable that a line application can also be carried out with one or more application heads on each side of the blank, the blank then continuing to move during the application process. Here, too, several application heads can work at the same time.

When the blank 14 provided with a binding substance has arrived in the shaping device 6, it is immediately centered there so that the stamp 7 can move down in order to press the prepared blank into the shaft 12 in the usual way. The side flaps of the blank 14 are folded upward in a known manner, the flap parts to be connected to one another being brought into contact with one another so that they can connect. Depending on the required setting time, the shaped blank 14 remains in the shaft 12 for a correspondingly long time, as can also be seen from FIG. The stamp 7 has now been retracted so that a new blank 14 can be inserted into the molding device 6. The stamp 7 then descends again, the lowest folding box 36 in the shaft 12 being ejected from the shaft below and brought onto a discharge conveyor 37.

In the example described above, the application head 13 or the application heads 13 are each assigned to the corresponding guide rails 2 or 3. In a modification, the procedure can also be such that one or more application heads are provided between the opposing application heads 13, if this is desired for corresponding blanks. Seen in the transverse direction of the guide rails are then z. B. three guns 13 are provided.

Claims (3)

1. Machine for producing folded boxes from blanks, in which a blank is withdrawn in each case from the bottom of an exchangeable magazine (4), is laid on two mutually parallel guiding rails (2, 3), is conveyed by means of a conveying system (21) to an exchangeable shaping system (6) comprising an end stop for completion of the folded box, wherein a bonding substance is applied at predetermined points of the precut blank by means of an applicator device (13) and in which the shaping system (6) comprises a plunger (7) as well as a shaft (12) situated thereunder and open at the top and bottom, characterised in that the two guiding rails (2, 3) are adjustable in their mutual horizontal spacing, that the magazine (4) has two downwardly extending, and mutually opposite lateral fixed stops (20) against which the displaceable guiding rails may be brought into abutment, that each guiding rail (2, 3) in a manner known per se carries at least one applicator head (13) adjustable in the longitudinal direction of the rails and vertically thereto, and that there is provided for each applicator head a switch (33) for placing the applicator head in operation, which is longitudinally adjustable, and operated by an entraining finger (23) of the return leg of an endless conveying system (21).

2. Machine according to claim 1, characterised in that the guiding rails (2, 3) are secured on transversely extending twin spars (16) by means of manually operable clamping elements (19).

3. Machine according to claim 1, characterised in that the endless conveying system (21) has additionally pusher device (24) in the area of its rear conveyor extremity, that the pusher device has a vertically sprung pusher arm (25) which is secured on an axially movable driving cylinder (28) and that a stop-operated reversing element (29) for the cylinder is provided at the front extremity of the driving cylinder.

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