ES1298830U - Envelope making machine (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Envelope manufacturing machine, comprising stations for cutting, creasing and folding the envelopes, characterized in that it comprises a device for applying silicone bands (10) comprising a reel (11) of silicone paper on one side, unwound by drive rollers (12) to a hot glue gun (14) configured to create intermittent beads of glue, a series of blades (15) for cutting the paper to generate strips and a suction roller (16) for gripping the strips. strips cut by suction, and configured so that the suction roller (16) commands the other elements of the application device by means of electronic cams. (Machine-translation by Google Translate, not legally binding)

Description

DESCRIPTION

envelope making machine

Object of the invention

The object of the present invention is an envelope manufacturing machine, of the tamper-evident gusset type. It is a machine that manufactures envelopes that have a reduced number of openings, replacing them with folds. In addition, it has silicone bands on the flap, to produce an inviolable closure.

It is applicable in the manufacture of stationery elements.

Background of the invention

Envelope manufacturing often involves cutting a template with numerous flaps and gluing the flaps together. This generates a series of openings with adhesive, so it is possible to open the envelope through one of them, hiding that it has been opened.

In the case of large-format envelopes, it is common to produce them with gussets and use silicone bands on the flap to close them. In current machines, the devices for applying these silicone bands carry out a radial electronic cam movement of the final transfer roller, while the other elements (knives, drive rollers...) are programmed to advance or carry out a number of constant of cycles according to the speed of passage of the envelopes. That is, they plan to cut N strips of silicone paper and prepare them constantly over time. They do not track the actual progress of the envelopes. Therefore, the transfer or delivery roller does not rotate at the same speed as the envelope and its transport belt, but speeds up or slows down depending on the passage of the envelopes. The sudden change in speed can produce wrinkles or deviations in the alignment of the silicone belts, creating quality problems.

The Applicant is not aware of any solution to these problems similar to the invention.

Description of the invention

The invention refers to an envelope manufacturing machine, according to the claims.

The envelope manufacturing machine comprises a series of stations for cutting, creasing and folding the envelopes and a device for applying silicone bands. This device for applying silicone strips comprises a reel of silicone-coated paper on one side, unwound by drive rollers and/or tensioning suction tapes, towards a hot glue gun. The hot glue gun is set to create intermittent beads of glue. The device also comprises a series of blades for cutting the paper to generate strips and a suction roller for gripping the cut strips by suction. The entire system is configured so that the suction roller commands the other elements of the application device by means of electronic cams. Thus, the operator programs the suction roller to coordinate the entire device and accelerations or braking are not carried out in the final step, resulting in an improved application. The presence of drive rollers and suction belts prevents the formation of wrinkles.

This machine is also applicable for placing reinforcements (paper strips with cold glue), for example in the easy-open area.

Other solutions are described later.

Brief description of the figures

In order to facilitate the understanding of the invention, a series of figures showing embodiment examples is provided. These examples cannot be considered limiting but only illustrative.

Figure 1: Shows an envelope like the one produced by the machine, in front view (A) and detail section (B).

Figure 2: (A-D) Shows several examples of ways to place the silicone bands on the flap of the envelopes.

Figure 3: Shows a side view of an example of the application device for silicone bands applicable to the machine.

Figure 4: Example of the speed of rotation of the blades in case of variable distance between silicone bands in the envelopes, corresponding to figure 2D.

Description of a preferred embodiment

The attached figures, and now described, show a preferred embodiment of the invention, being therefore mere examples.

Figure 1 shows an example of an envelope made according to the invention. It comprises two larger faces (1) with a flap (3) closing a mouth (31) and two bellows sides (4). Each of the bellows sides (4) has at least five folds, so that it generates two or more consecutive angles (41), in a "W" shape or similar. In figure 1, the angles (41) are somewhat shorter on the side that joins each other, and longer on the larger faces (1).

The envelope is formed by folding a sheet so that the two ends of the sheet form the mouth and the sides are folded and adhered to each other forming the bellows (4), so that each larger face (1) has at least an angle (41). The union of the angles (41) is made by adhesive. In this way, the union is resistant but at the same time difficult to open surreptitiously.

For simplicity of manufacturing, the number of angles (41) is even and the same number is arranged on each side of the joint.

The manufacturing steps are as follows. First, the material is uncoiled and one or both of the larger faces (1) are printed, monochrome or in color. Printing can be prior to winding.

Secondly, a series of longitudinal slits (5) is made, on one or the other major face (1). The creases (5) are made on one or the other major face (1) alternately, and are intended to define fold lines when creating the angles (41).

Next, the flap (3) is cut and the lateral cuts (6) thus generated are removed, normally by suction.

In the next stage, the folds of the bellows (4) are made using the creases (5) and some guides. The adhesive is applied inside at least one corner (41) of the bottom area (furthest from the flap (3) of the envelope).

For the final folding and cutting, two transversal creasings (7) are created, one for the flap (3) and another for the bottom of the envelope.

Adhesive is placed in the area of the angles (41) that will overlap to close the sides of the envelope. The envelope is separated from the reel, by means of a cut and a change of speed, and it is folded by the transversal crease (7) of the bottom. The angles (41) adhere by contact.

If desired, an easy-open (8) or area of weakness can be generated on the flap (3), so that the user can open the envelope, tearing it. This shape ensures that any opening is marked. This easy opener (8) can be generated at various points in the procedure.

Likewise, a final crease (9) can be made, close to the flap (3) to generate a final folding area that ensures inviolability. This creasing is preferably done once the bottom has been folded, to ensure that it remains on both larger faces (1) without the need to make two final creasings (9) that coincide when folding the envelope.

At this point, the envelopes are staggered, with a certain distance so that the flaps (3) stand out, showing little or nothing of the larger faces (1). At this point silicone bands (10) are applied with a hot adhesive (“ hotmelt'). The silicone bands (10) are produced separately and applied at that point in the procedure.

Once the silicone bands (10) have been applied, the envelope is ready for storage, packaging and distribution.

The device for applying silicone bands (10) is shown in Figure 3. It comprises a coil (11) of silicone-coated paper on one side, generally on the inside. The silicone paper is unwound at the required speed by means of drive rollers (12). Thanks to the drive rollers (12) and one or more suction belts (13) the silicone paper is kept taut. Suction belts are belts, normally toothed by its interior to prevent slipping, with holes that allow the passage of air. When they are arranged above a suction hopper, the passage of air through the holes sucks in any material, such as the silicone band (10), that is arranged on the other side of the belt.

A hot glue gun (14), glue, creates intermittent beads of adhesive on the silicone face. The drive rollers (12) drive the silicone strip (10) to ensure that it is taut and the hot glue (14) is applied properly. The silicone band (10) is stretched between the roller drive at one end and the suction belts at the other, leaving the adhesive laminating gun between them.

A series of blades (15), for example one fixed and another mobile (rotating) cuts the silicone paper in an area without adhesive. A suction roller (16) grabs the cut strip by suction and takes it to the area of the flap (3) where it is applied. Thus, when the envelopes pass through the transport belt (17), in a staggered position, the corresponding cut strips are placed according to the planned arrangement (see examples of alternatives in figure 2).

This allows the device to deliver already cut strips with adhesive, so that the suction roller (16) can be coordinated with the advance of the envelopes. In other words, the suction roller (16) delivers the strips of adhesive at the same speed as the envelopes advance, without any relative movements. This avoids positioning problems, wrinkles, twists and related problems in the manufacture of the envelope. The rest of the elements: drive rollers (12), blades (15) and suction belts (13) are coordinated with the suction roller (16) by means of electronic cams. For example, in the examples of Figure 2, distribution modes of the silicone bands (10) can be seen that place them with a constant pitch and distribution modes that place them at different distances from one another (for example, in Figure 2D ). This pitch difference is measured with suction roller position sensors (16) and the instantaneous speed is translated into an instantaneous speed of the other elements. Figure 4 shows an example of the speed of the blades (5) when the distance between silicone bands (10) is variable.

Claims (1)

1. Envelope manufacturing machine, comprising stations for cutting, creasing and folding the envelopes, characterized in that it comprises a device for applying silicone bands (10) comprising a reel (11) of silicone paper on one side, unwound by drive rollers (12) to a hot glue gun (14) configured to create intermittent beads of glue, a series of blades (15) for cutting the paper to generate strips and a suction roller (16) for gripping the strips. strips cut by suction, and configured so that the suction roller (16) commands the other elements of the application device by means of electronic cams. 2- Envelope manufacturing machine, according to claim 1, characterized in that the device for applying silicone bands (10) comprises suction belts (13) that tension the silicone paper in collaboration with the drive rollers (12).