CONTAINER PRE-CUTTING SYSTEM

Abstract

This invention relates to a container pre-cutting system, applicable to container forming machines (4) with laminar material (3) that provide intermittent advances to the laminar material with a length according to an advance step of the machine; said system being suitable for making a lower pre-cut (32) on the lower surface and an upper pre-cut (32) on the upper surface of the laminar material (3). The system comprises a lower pre-cutting device (1) by laser, with at least one laser head (15), and an upper pre-cutting device (2) by blade or by laser. The pre-cutting devices (1, 2) are separated in the advance direction of the laminar material (3) by a length equal to a multiple of the advance step of the machine.

Claims

1. A container pre-cutting system for container forming machines with multilayer, bilayer or single-layer laminar material, that provide intermittent advances of laminar material of a length according to an advance step of the machine, said container pre-cutting system comprising: a lower pre-cutting device and an upper pre-cutting device configured to make a lower pre-cut and an upper pre-cut in a laminar material; wherein the lower pre-cutting device comprises at least one laser head, which projects a laser beam from a lower area, through a space existing between consecutive containers of a multipack container and defines a lower pre-cutting line in an area of the laminar material forming a bridge joining said containers.

2. The container pre-cutting system according to claim 1, wherein the upper pre-cutting device includes an upper blade configured to move vertically between an inoperative upper position and an operative lower position, and wherein in the operative lower position, the upper pre-cutting device is configured to provide an upper pre-cut to the laminar material.

3. The container pre-cutting system according to claim 1, wherein the upper pre-cutting device and the lower pre-cutting device are separated in an advance direction of the laminar material by a length equal to a multiple of the advance step of the container forming machine.

4. The container pre-cutting system according to claim 2, wherein the upper pre-cutting device and the lower pre-cutting device are separated in an advance direction of the laminar material by a length equal to a multiple of the advance step of the container forming machine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] As a complement to the description being made, and for the purpose of helping to make the features of the invention more readily understandable, this specification is accompanied by a set of drawings which, by way of illustration and not limitation, represent the following.

[0020] FIG. 1 shows a schematic elevation view of an exemplary embodiment of the container pre-cutting system according to the invention, wherein the lower pre-cutting device, provided with a laser head, and the upper pre-cutting device equipped with a cutting blade can be seen, and longitudinally separated in the advance direction of containers formed in a multilayer, bilayer or single-layer material.

[0021] FIG. 2 shows an elevation view of an embodiment variant of the lower pre-cutting device, provided with two laser heads.

[0022] FIG. 3 shows a detailed enlargement of a cross section of the laminar material as the lower pre-cut is made by means of a laser.

[0023] FIG. 4 shows an elevation view of the upper pre-cutting device as the upper pre-cut is made and a detailed enlargement of the laminar body wherein the lower pre-cut made previously and the making of the upper pre-cut can be seen.

DETAILED DESCRIPTION

[0024] In FIG. 1 the container pre-cutting system comprises a lower pre-cutting device (1) and an upper pre-cutting device (2) intended to be mounted on a container forming machine (4), made with multilayer, bilayer or single-layer laminar material (3) and which, when actuated, make both pre-cuts in the lower surface and in the upper surface of the laminar material (3).

[0025] It must be mentioned that in the aforementioned FIG. 1, the lower pre-cutting device (1) and the upper pre-cutting device (2) are in this order in the advance direction of the laminar material (3), although it could be in the opposite order, since the order does not affect the operation of the system.

[0026] The lower pre-cut device (1) and upper pre-cut device (2) are longitudinally separated in the advance direction of the laminar material (3) by a length equal to a multiple of the advance step of the container forming machine, such that the lower and upper pre-cutting lines corresponding to the same area of laminar material (3) are not made simultaneously, but rather in two successive phases.

[0027] In said FIG. 1, the lower pre-cutting device (1) comprises: a laser head (11), which projects a laser beam (12) from a lower area, through the space existing between consecutive containers (4) of a multipack container and defines a lower pre-cut line in the area of the laminar material forming the bridge joining said containers.

[0028] The upper pre-cutting device has in this embodiment a vertically-movable blade, as detailed later on.

[0029] To make an upper pre-cut in the material in the same area wherein a lower pre-cut has been made it is necessary for the laminar material to move a specific number of advance steps of the machine, until said area reaches the upper pre-cutting device (2), such that a sufficient amount of time passes to release the stresses produced in the laminar material.

[0030] In the embodiment variant shown in FIG. 2, the lower pre-cutting device comprises two laser heads (11) for making lower pre-cutting lines (31) as shown schematically in FIG. 3.

[0031] FIG. 4 shows an embodiment of the upper pre-cutting device (2) shown in FIG. 1 which is shown in FIG. 4 comprises: a lower die (20) and an upper blade (21) mounted with the possibility of relative vertical movement with respect to a floating stop (22) in turn provided with limited vertical movement with respect to a punch plate (23); said upper blade (20) being mounted on calibrated springs (24).

[0032] When the upper pre-cutting device (2) is actuated, the floating stop (22) presses the laminar material (3) against the lower die (20) and the upper blade (21) penetrates the upper surface of the laminar material (3), defining the upper pre-cut (32) in the same.

[0033] As can be seen in the detailed enlargement of FIG. 4, the lower pre-cut (31) and the upper pre-cut (32) are slightly separated in the advance direction of the laminar material (3), the lower die (20) in the area facing the upper blade (21) having a recess (25) that allows for a certain elastic deformation of the laminar sheet (3) when making the upper pre-cut (32), which contributes to reducing the stresses of the material in the pre-cutting area.

[0034] Having sufficiently described the nature of the invention, in addition to an example of preferred embodiment, it is hereby stated for the relevant purposes that the materials, shape, size and layout of the described elements may be modified, provided that it does not imply altering the essential characteristics of the invention claimed below.