Splicing Device and Method for Splicing Sheets of Material

The present disclosure relates to a splicing device and a method for splicing sheets of material.

In manufacturing processes of consumables, for example heat-not-burn articles where an aerosol generating substrate is heated rather than combusted, the articles or elements of these articles are manufactured in a continuous process. Often, a band of material is unwound from a bobbin and spliced to a band of the same material unwound from a new bobbin. Such a process should be automatic in order to keep production machines continuously running. Known splicing devices are adapted for splicing a specific material used for the manufacture of a specific element. However, in particular heat-not-burn articles comprise elements of materials having different physical and chemical characteristics and known splicing devices do not work properly with such different materials.

Thus, there is need for a splicing device suitable for splicing different kinds of sheets of materials. In particular, there is need for a splicing device that is suitable for splicing tobacco containing sheet material, as well as suitable for splicing paper and plastic sheets.

According to an aspect of the present invention, there is provided a splicing device comprising a punch plate and a counter plate, wherein the punch plate and the counter plate are relatively movable versus each other for splicing two sheets of material arrangeable in between the punch plate and the counter plate. The punch plate comprises an array of splicing protrusions and the oppositely arranged counter plate comprises an array of splicing holes. The array of splicing holes comprises a number of splicing holes and the array of splicing protrusions comprises a number of splicing protrusions, wherein the number of splicing holes is at least the same as the number of splicing protrusions, and wherein a position of the splicing protrusions in the array of splicing protrusions corresponds to a position of the splicing holes in the array of splicing holes.

The use of splicing protrusions and corresponding splicing holes allows to possibly perforate one or even both sheets of material to be spliced, in addition to a mechanical deformation of the two sheets of materials in the region of the splicing protrusions and corresponding splicing holes. Thus, a very expressed interpenetration of the two sheets of material is achieved and leads to a very strong splice. The splice may be even stronger if the material to be spliced is prone to plastic deformation or partial melting.

The splicing device according to the invention is available, for example, for conventional paper sheets, for plastic sheets, but also for specially fibrous sheets as the splicing protrusions may penetrate the fibers in a fibrous sheet material, or also for metal sheets that are not easily spliced all.

Preferably, the punch plate comprises all splicing protrusions and the counter plate comprises all splicing holes.

However, splicing protrusions and splicing holes may also be provided on both, the punch plate and the counter plate. In some embodiments of the splicing device, both the punch plate and the counterplate comprise an array of splicing protrusions and an array of splicing holes. In these embodiments, preferably the positions of each of the splicing protrusions of the punch plate correspond with the positions of a splicing hole in the counter plate and vice versa.

In embodiments where splicing protrusions and splicing holes are provided on the punch plate and on the counter plate, preferably, splicing protrusions and splicing holes are arranged in an alternating manner on each of the punch plate and the counter plate.

In the splicing device, the positions of splicing protrusions correspond to positions of splicing holes when the splicing device is in a closed splicing position. Preferably, the positions of splicing protrusions also correspond to positions of splicing holes when the splicing device is in an open position, thus when the punch plate and the counter plate are arranged distanced from each other.

Preferably, a splicing protrusion may be inserted in a splicing hole when punch plate and counter plate are closed for splicing the sheets of material.

Preferably, splicing protrusions and splicing holes are arranged along a straight line corresponding to a linear direction of movement of the punch plate and counter plate versus and away from each other.

Preferably, the punch plate and the counter plate are arranged parallel to each other, in an open and in a closed position of the splicing device. Splicing may then be performed with a linear movement of one or both plates toward the other plate or toward each other.

Punch plate and counter plate may have individual shapes and sizes. For example, a counter plate may be an integrated part of a transport surface for the sheets of material.

Preferably, punch plate and counter plate have same dimensions in length and width. A width of a plate may correspond to a transport direction of a sheet material, while a length of a plate may then correspond to a direction perpendicular to the transport direction in a plane of the sheet material. Same dimensions in length and width provide the advantage of a symmetric set-up of the splicing device. The splicing device is preferably arranged parallel or perpendicular to a transport direction of the sheets of material. Accordingly, a length or width of a punch plate is arranged parallel or perpendicular to a transport direction of the sheets of material. This may keep a spliced portion as small as possible. However, a splicing device may also be arranged at an angle to the transport direction of the sheets of material.

The splicing protrusions may have any form that allows to deform and preferably penetrate and perforate at least one of the sheets of material arranged above each other for splicing. Preferably, the splicing protrusions have a shape and size that allows to deform and preferably penetrate and perforate both of the sheets of material arranged above each other for splicing.

Preferable, the splicing protrusions have an elongate shape.

Preferably, the splicing protrusions have a tip end arranged most distantly from the punch plate, when the splicing protrusion is provided at the punch plate.

Preferably, the splicing protrusions have a tip end arranged most distantly from the counter plate, when the splicing protrusion is provided at the counter plate.

Preferably, the splicing protrusions are splicing pins.

Preferably, the splicing protrusions have a pointed tip, a rounded tip or a tip provided with cutting edges. Pointed and rounded tips are reliable means in splicing processes of a wide range of sheets of material. The use of splicing protrusions, in particular splicing pins, provided with cutting edges, is advantageous for strong materials, such as for example metal sheets, or for elastic materials, such as for example plastic sheets.

As used herein with reference to the invention, the term “sheet” describes a laminar element having a width and length substantially greater than the thickness thereof.

The splicing protrusions may, for example, have a round, circular, triangular, polygonal, square or star-shaped cross-section. The cross sections of the splicing protrusions may be the same over a length of a splicing protrusion or may vary over a length of a splicing protrusion. The length of a splicing protrusion corresponds to the extension of the splicing protrusion from the surface of the plate the splicing protrusion is provided.

Corresponding splicing holes may have a same or a different size than a splicing protrusion. In particular, a splicing hole may have a same cross section than a corresponding splicing protrusion. A cross section and depth of a splicing hole is at least as large as a corresponding splicing protrusion in order for a splicing protrusion to fit into the splicing hole. However, a cross section of a splicing hole does not have to be the same as the cross section of a splicing protrusion. In particular, a splicing hole may be a circular hole receiving various forms of splicing protrusions.

Preferably, splicing holes have a circular, polygonal or triangular or square cross section.

Preferably, splicing holes are drill holes.

A length of a splicing protrusion may be in a range between 1 millimeter and 50 millimeter. Preferably, a length of a splicing protrusion is in a range between 3 millimeter and 20 millimeter. More preferably, a length of a splicing protrusion is in a range between 4 millimeter and 10 millimeter, for example 6 millimeter.

A cross section area, for example a diameter, of a splicing protrusion may, for example, be in a range between 0.5 millimeter and 20 millimeter. Preferably, a cross section area, in particular a diameter, of a splicing protrusion is in a range between 1 millimeter and 10 millimeter. More preferably, a cross section area in particular a diameter, of a splicing protrusion is in a range between 2 millimeter and 5 millimeter, for example 3 millimeter.

A cross section area, in particular a diameter, of a splicing hole may, for example, be in a range between 0.5 millimeter and 20 millimeter. Preferably, a cross section area, in particular a diameter, of a splicing hole is in a range between 1 millimeter and 10 millimeter. More preferably, a cross section area, in particular a diameter of a splicing hole is in a range between 2 millimeter and 5 millimeter, for example 3 millimeter.

Dimension and sizes in these rages have provided good splicing results for a large variety of sheet materials to be spliced, for example fibrous sheets, sheets of tobacco material, plastic sheets and also metal foils.

Preferably, all splicing protrusions of an array of splicing protrusions have a same length and a cross section area. Preferably, all splicing protrusions on a punch plate and on a counter plate have a same length and a same cross section area.

Preferably, all splicing holes of an array of splicing holes have a same cross section area.

Preferably, all splicing holes have a same shape.

Identical forms of splicing protrusions and identical forms of splicing holes of arrays or in total, may provide a homogenous spliced portion. However, parts of an array of splicing protrusions and corresponding splicing holes may have different forms or sizes than other parts of the same array, in order to vary a splice. For example, a stronger splice or a weaker splice may be manufactured in some areas of a spliced portion than in other areas of the spliced portion.

A total number of splicing protrusions and corresponding splicing holes may be chosen according to the size of one or more spliced portions to be manufactured, the size of the material to be spliced, or may be adapted to a material to be spliced.

A total number of splicing protrusions may, for example, be between 2 and 250. Preferably, a total number of splicing protrusions is between 10 and 200. More preferably, a total number of splicing protrusions is between 20 and 100, for example 70.

The total number of splicing holes is at least the same as the total number of splicing protrusions. Preferably, the total number of splicing holes corresponds to the total number of splicing protrusions.

Splicing protrusions may be formed integrally with a plate or may be attached to the plate. Splicing protrusions may comprise or may be made of a same material as a plate the protrusion is extending from.

Splicing protrusion may comprise, for example, steel, preferably stainless steel, polycarbonate, ceramic, thermoset material such as for example Bakelite®, or silicone.

Splicing protrusions may be made, for example, of steel, preferably, stainless steel, polycarbonate, ceramic, thermoset materials such as for example Bakelite®, or silicone.

The splicing device, in particular the punch plate and the counter plate, more particularly the splicing protrusions, may be specifically treated, for example to enhance endurance or to prevent adhesion of the sheet material to the splicing parts.

For example, the splicing protrusions may be coated or thermochemically treated.

The splicing device may comprise a liquid supply for supplying a liquid to a sheet of material to be spliced. To enhance the strength of a splice, a liquid may be applied to one or to both sheets of material.

Some materials are tacky as such, for example, tobacco containing cast leaf, get tacky or tackier when provided with a liquid.

Preferably, a liquid is a liquid as used in the food industries.

Preferably, a liquid is water or a liquid natural adhesive such as, for example, fish glue or egg white.

Preferable, a liquid supply is adapted for supplying water or a liquid natural adhesive such as, for example, fish glue or egg white.

Some materials get tacky or more easily deformed when heated. For example, some plastic materials have a low melting temperature or a low glass temperature, for example polylactic acid. Polylactic acid sheets are used, for example, in the manufacture of filters for smoking articles or heat-not-burn articles.

Upon heating the sheets of material while splicing may enhance the strength of a splice.

The splicing device may comprise a heater for heating parts of at least one of the punch plate and the counter plate.