EP0451758B1 - Movable upper tool for the separation of the forms in a packaging material production machine - Google Patents

Abstract

The invention concerns a movable upper tool for a station for separating blanks in a machine working on sheets for the purpose of producing packages. The tool comprises a horizontal plate (1) pierced with a large number of openings (10) and on the lower surface of which are fitted punches (2, 2') for separating blanks. The upper surface of each punch (2, 2') is provided with VELCRO strips (21) intended to engage with a VELCRO layer (12) glued to the lower surface of the plate (1) for securing the punch (2, 2') with respect to the plate (1). <IMAGE>

Description

The present invention relates to a mobile upper tool used in a station separation station in a machine for working sheet or sheet elements for the production of packaging.

• impression sur une feuille d'un grand nombre de motifs (ou figures) dont chacun est relatif à un seul emballage;
• découpage de la feuille en différentes poses (ou flancs) dont chacune comprend un seul motif imprimé; et
• pliage-collage de chaque pose en vue de former un emballage à l'état plié.

The production of packaging goes through three successive stages:

• printing on a sheet of a large number of patterns (or figures) each of which relates to a single package;
• cutting the sheet into different poses (or sides) each of which comprises a single printed pattern; and
• folding and gluing each pose to form a package in the folded state.

After cutting, so that the whole cut sheet can be transferred (in principle by means of a gripper bar mounted on a chain of chains) to the following waste ejection stations (consisting of areas of the sheet located between each laying and excluded from the final packaging) and receiving the sheet, all the poses of the same sheet are still held together by means of small attachment points which correspond to very small notches (not cutting) made in the press cutting nets.

• soit de former une pile de feuilles composées chacune de toutes ses poses réunies entre elles par les points d'attache;
• soit de former simultanément plusieurs piles de poses qui ont été séparées entre elles par ruptures des points d'attache dans une station antérieure dite de séparation des poses.

At the receiving station, as required, it should be possible:

• either to form a pile of sheets each made up of all its poses joined together by the attachment points;
• or to simultaneously form several stacks of poses which have been separated from one another by ruptures of the attachment points in an anterior station known as the separation of the poses.

It is known to use, in the blanking station, a movable upper tool and a fixed lower tool. The upper tool is constituted by a set of punches, and the lower tool by a matrix with openings, the movable upper punches forcing the poses through the openings in the lower matrix by causing the rupture of the various attachment points which connected either each of the poses between them, or the marginal poses to a peripheral waste of the leaf. The separation tools must therefore be adapted to the shape and arrangement of the poses of each new series of sheets to be worked. In general, the punches are mounted, in registration with respect to the cutting lines of the press, on the underside of a plate fixed to an upper mobile tool-holder frame of the station separation station. Below and opposite each punch is a corresponding opening or mesh of the lower matrix made up of bars. The bars are arranged so as to overlap to form a grid or matrix whose meshes have the dimensions of the poses to be separated.

To avoid the need to manufacture new tools for separating the poses for each new series of sheets, it has been proposed, in patent CH-A-617886, to mount the punches horizontally displaceable along bars fixed on a vertically movable frame. The fixed lower matrix is composed of crossed bars and displaceable so as to form a grid whose meshes are of adjustable dimensions. If these adjustable tools have already greatly simplified and accelerated their adaptation to a new sheet format, the method of fixing the punches on the underside of the upper tool, described in patent CH-A-617886, has the drawback of '' require relatively complicated means of implementation; in fact, it is first necessary to position the punches on the bars, and finally to lock in position the tools which fix the punches on the bars. All these operations are relatively long and tedious.

Another way to make the upper tool is to fix the punches by gluing on the underside of a board. In this case, for each new job, a new superior tool must be executed.

The object of the present invention is therefore to produce a device for separating the blanks which eliminates the drawbacks mentioned above.

This object is achieved by means of a blanking device according to claim 1.

• la figure 1 est une vue simplifiée de côté (en coupe partielle selon B - B de la figure 2) d'un outil supérieur selon l'invention;
• la figure 2 est une vue de dessous selon A - A de la figure 1; et
• la figure 3 est une vue de dessus d'un poinçon de séparation.

In order to facilitate understanding of the invention, an embodiment of the device for separating poses is now described with reference to the appended drawing in which:

• Figure 1 is a simplified side view (in partial section along B - B of Figure 2) of an upper tool according to the invention;
• Figure 2 is a bottom view along A - A of Figure 1; and
• Figure 3 is a top view of a separation punch.

The upper tool comprises a large wooden plate 1, or other light material, the dimensions of which correspond to the format of the sheet, the poses of which must be separated from each other by breaking their attachment points. The plate 1 is mounted, in a known manner, on an upper mobile tool-holder frame of the blanking station. Approximately the entire surface of the plate 1 is gridded with rectangular openings 10 (only a few of which are shown in Figure 2) intended to allow air to pass during its working movement from top to bottom and from bottom to top. With the exception of the openings 10, almost the entire lower surface is covered, by gluing or other means, with a fixing layer VELCRO 12. Against the lower face of the plate 1 is fixed a large number of wooden punches 2 of separation of the poses. Each punch 2, in principle in the form of a hollow body, has a flat upper face intended to be pressed against the lower face of the plate 1, and a lower face covered with foam 22 intended to come into contact with the laying. . Other punches 2 'can also be made of resilient polyurethane and therefore without the foam layer 22. The upper face of each punch 2, 2' is covered with two narrow strips VELCRO 21 intended to come into engagement with the layer VELCRO 12 of plate 1.

Tests have shown that it is preferable not to cover with VELCRO the entire upper surface of each punch 2, 2 'to make their installation easier. Indeed, if the surfaces in engagement of the VELCRO layers 12, 21 for each punch 2, 2 ′ are too large, their fixing is difficult. It may be explained by the fact that the end of the multitude of hooks which make up each VELCRO layer requires, for their mutual interlacing, a lateral displacement which is only authorized in the case of narrow bands. In addition, the VELCRO bands 21 must be arranged as close as possible to the extreme and opposite lateral edges of the punch 2, 2 ′ so as to increase the stability of the latter when it is mounted on the plate 1.

Although it is preferable that the punches 2, 2 'are hollow, so that their opening 24 allows, in association with the openings 10 of the plate 1, the escape of air, it is possible to envisage full punches.

The punches 2, 2 'can, of course, have a completely different shape than rectangular.

It should be noted that the fixing by VELCRO described above is especially well suited in the particular case; indeed, the punches 2, 2 ′ are in principle subjected, during their work, only to forces directed perpendicular to the plate 1, direction in which the action of VELCRO is particularly effective.

In addition, the assembly and disassembly of the punches 2, 2 'relative to the plate 1 are simplified to the extreme. In the case of mounting by robot, this method of fixing by VELCRO is ideally suited since there is no fixing element, such as screws or the like, to be actuated; in fact, seen from the angle of the robot, the mounting of the punches 2, 2 'is similar to a simple positioning supplemented by a more or less significant pressure that the robot must exert on the punch 2, 2' to engage the two VELCRO layers 12, 21. Since the vast majority of punches 2, 2 'of a tool generally have the same shape and dimension, the robot specialist immediately sees how easy the fixing by VELCRO makes it easy here to prepare the tool for a new format, once the way in which the punches 2, 2 'must be distributed on the plate 1 is determined and stored in the robot control.

Claims (4)

1. Movable upper tool for a blank-separating station situated within a sheet processing machine used for producing packages, comprising a horizontal plate (1) on the lower side of which the upper side of blank-separating blocks (2, 2') are fitted,
   characterized by:

   - the plate (1) being provided with numerous apertures (10) destined to let the air pass through during the motion of the plate,

   - the lower side of the plate (1) being covered at least partially with a first layer (12) of VELCRO material or similar,

   - the upper side of every block (2, 2') being covered at least partially with a second layer (21) of VELCRO material destined to adhere on the said first layer (12) of VELCRO material so as to ensure the fitting of the block (2, 2') on the plate (1).
2. Tool according to claim 1, characterized by the second layer (21) of VELCRO material having the shape of narrow strips situated on the far and opposite edges of the said upper side.
3. Tool according to the claims 1 or 2, characterized by the blocks (2') being made out of resilient polyurethan.
4. Tool according to one of the aforementioned claims, characterized by the apertures (10) being aligned with two directions perpendicular to one another.

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