Patent Description:
The term "cigarette" is used to denote any rod-shaped article comprising at least a filter, a cigarette segment designed to release an inhalable substance, and a connecting strip disposed in such a way as to connect the filter and the cigarette segment to each other. The cigarette may be a traditional cigarette, where inhalation follows burning the free end of the cigarette segment, or it may be an electronic cigarette, where inhalation follows heating (without burning) the free end of the cigarette segment (specifically, with a carbon tip).

The cigarette segment may comprise traditional tobacco wrapped in paper or it may be an aerosol-generating element, that is,
a product containing tobacco of the type suitable for heating but not burning (heat-not-burn).

In this case, the tobacco may be, for example, pre-treated, reconstituted or homogenized tobacco.

Typically, rod-shaped articles of the type mentioned above comprise a wrapper - of paper, for example - in which the articles are wrapped.

The machines which make the rod-shaped articles, therefore, typically include rolls of wrapping material of various kinds which are unwound into continuous webs and then processed, if necessary, and used, for example, to make connecting strips for the cigarettes or coverings for the continuous rods of tobacco or filter material to make the filters or the cigarette segments.

To meet the wide range of needs of manufacturers of rod-shaped articles, the webs of paper are often further processed before being used to make the article. Web processing may comprise applying features such as a commercial logo (by embossing), knurling on the paper (also by embossing) and, in the case of electronic cigarettes (with carbon tip) an inner layer of metallic material.

These features are normally applied at very high speeds: a very high level of precision is therefore required of the machine for application to be carried out correctly, at the right position, and to meet acceptability criteria. In many cases, the station where the features are applied are nevertheless subject to faults and malfunctioning which may lead to interruptions or irregularity which reflect negatively on the integrity and/or quality of the article.

Different methods for making rod-shaped smoking articles are known.

For example, <CIT> discloses a cigarette making method in which a surface of a running paper web is provided with a pattern and a marker disposed near the pattern. The method comprises detecting the marker (which can be detected more easily than the pattern) using sensors, so as to adjust the conveying speed of the paper web through a cutting unit for cutting the paper web, based on the detections performed.

The method described has one drawback, however. More specifically, the method described has the drawback of using both the pattern and the marker as a reference; since the pattern on the surface of the web may be incorrectly positioned (due to errors when it is applied), adjusting the cutting operation based (also) on the pattern may have a negative effect on the cutter, making cutting imprecise.

<CIT> discloses a method for making cigarettes comprising a wrapping material which in turn comprises an additive used to control cigarette burning. The method comprises detecting, with a sensor, one or more marks applied on the surface of the wrapping material which, after wrapping, is the surface that is visible to the user. The marks are used to synchronize the cutting of the tobacco segment with the concentration profile of the additive on the wrapping material. This method has several drawbacks: in particular, positioning errors may occur (during the step of applying the marks); these mark positioning errors lead to imprecise cutting of the tobacco segment and have a negative effect on subsequent processes.

Patent documents <CIT>, <CIT>, <CIT> and <CIT> provide further examples of methods for processing a web of wrapping material; however, also these methods are affected by the aforementioned drawbacks.

The aim of this invention is to provide a method and an apparatus for processing a web of wrapping material used to make smoking articles to overcome the above mentioned drawbacks of the prior art.

More specifically, this invention has for an aim to provide a method and an apparatus for processing a web of wrapping material where a mark can be positioned in a particularly precise and reliable manner using a manageably sized, easy to make system (which can be applied on newly made machines or retrofitted on existing machines). Further aims of the invention are to provide a web of wrapping material and a method and an apparatus for making smoking articles.

These aims are fully achieved by the method for processing a web of wrapping material forming the object of this invention and as characterized in the appended claims.

According to the invention, the method comprises a step of feeding the web of wrapping material. In the step of feeding, the web advances by a predetermined quantity (i.e., length). The predetermined quantity corresponds to a length of a stretch of web used to make a single cigarette.

Preferably, the web is fed continuously.

According to the invention, the method comprises a step of making a feature (at least one) on the web.

According to the invention, the method comprises a step of applying a mark on a surface of the wrapping material. A mark may be, for example, a notch made on the wrapping material in order to control subsequent operations. In effect, in a line for the manufacturing of smoking articles, buffers may be provided which involve temporarily stopping the feeding of the articles; it is therefore necessary to detect each article as it enters the machine (or machines), or after it has entered, so as to be able to program the subsequent operations. And it is the marks made on the articles that are used for the purpose of detecting the articles.

The steps of feeding, of making a feature (at least one) on the web and of applying a mark are repeated cyclically with a predetermined periodicity.

According to the invention, the method comprises a step of generating a synchronization signal. The synchronization signal represents the periodicity.

In an embodiment, the synchronization signal is generated by a timer. In an embodiment, the synchronization signal is generated at regular intervals. Using the timer, the duration of the regular time intervals can be set as a function of the required periodicity (for example, based on the size of the smoking articles to be made).

According to the invention, the mark is applied by means of a shaft controlled by the synchronization signal. That way, each mark is spaced from the next by a predetermined distance. In effect, the marking shaft is configured to make each mark at a respective instant, determined by the synchronization signal; the time interval between the instants one mark and the next are made, governed by the synchronization signal, determines the distance (on the web) between that mark and the next.

The expression "controlled shaft" or "shaft" is used to mean an actuator (for example, an electric motor) controlled by the control unit and connected to a movable element to drive it; that way, a given movement is measured (for example by an encoder or another sensor) and controlled by the control unit through the actuator, in such a way that a tool can be positioned precisely at an arbitrary point along its stroke.

According to the invention, the (at least one) feature on the web is controlled by the synchronization signal. In effect, the processing shaft is configured to make each feature at a respective instant, determined by the synchronization signal; the time interval between the instants one feature and the next are made, governed by the synchronization signal, determines the distance (on the web) between that feature and the next. Further, if both the marking shaft and the processing shaft are controlled by the synchronization signal, that synchronization signal determines the distance (on the web) between each mark and each respective feature.

Thanks to the synchronization signal which controls the position of the mark, it is possible to position the mark repeatably with a very high degree of precision both relative to the preceding and the following marks and relative to the other features made on the web (and also controlled by the synchronization signal.

In an embodiment, the step of applying the mark is carried out on an inside surface of the wrapping material. By inside surface of the wrapping material is meant the surface which is intended to face the inside of the corresponding article when the article has been completed. The outside surface, on the other hand, is the surface opposite to the inside surface and intended to face the outside of the corresponding article when the article has been completed.

In an embodiment, the step of applying the mark comprises a step of engraving (the wrapping material). In an embodiment, the step of applying the mark comprises a step of printing (the wrapping material). In an embodiment, the step of applying the mark comprises a step of perforating (the wrapping material). In an embodiment, the step of applying the mark comprises a step of tearing (the wrapping material). In an embodiment, the step of applying the mark comprises a step of applying an additional material (on the wrapping material). Preferably, the mark is applied on the inside surface of the wrapping material.

In an embodiment, the step of applying the mark comprises a step of inkjet printing (on the wrapping material). In an embodiment, the step of applying the mark comprises a step of laser engraving (the wrapping material).

In an embodiment, the step of making a feature (at least one) includes (a sub-step of) applying a logo. The logo is applied on at least one surface of the wrapping material (preferably the outside surface). In an embodiment, the logo is applied by (a first step of) embossing the wrapping material. Each logo, thanks to the synchronization signal which governs its application, is spaced from the next by a predetermined distance.

In an embodiment, the step of making a feature (at least one) includes (a sub-step of) embossing a surface of the wrapping material to create a knurled portion. Hereinafter, by first step of embossing is meant the process by which the logo feature is applied, whilst by second step of embossing is meant the process by which the knurled portion is made. Preferably, the (second) step of embossing is carried out both on the inside surface and on the outside surface of the wrapping material. The knurled portion may have an aesthetic function; its function may also be to make it easier for the consumer to hold the cigarette.

In an embodiment, the step of making a feature (at least one) includes (a sub-step of) applying a metallic element made of (or comprising) a metallic material (preferably aluminium) on a surface of the wrapping material. The metallic element made of (or comprising) a metallic material is applied preferably on the inside surface of the wrapping material. Each metallic element is spaced from the next by a predetermined distance (thanks to the synchronization signal which governs its application).

In an embodiment, the method comprises a step of controlling the step of processing the wrapping material and the step of applying the mark in such a way that the mark is at a predetermined position (that is, at a predetermined distance) from the logo. The control is preferably performed as a function of the synchronization signal.

Preferably, the method comprises the following steps (or sub-steps), in succession:.

These steps are controlled by the synchronization signal. This allows achieving a high degree of precision in synchronizing (or timing) the steps (or sub-steps).

This invention also relates to an apparatus for processing a web of wrapping material used to make smoking articles.

According to the invention, the apparatus comprises a feeding device. The feeding device configured to feed the web of wrapping material (preferably continuously) to advance it by a predetermined quantity (that is, length) corresponding to a length of a stretch of web used to make a single article.

According to the invention, the apparatus comprises a processing shaft. The processing shaft is configured to create a feature (at least one) on the web.

According to the invention, the apparatus comprises a marking shaft. The marking shaft is configured to apply a mark on a surface of the wrapping material.

According to the invention, the apparatus comprises a device for generating a synchronization signal. The processing shaft and the marking shaft are controlled as a function of the synchronization signal. That way, the mark is positioned precisely relative to the (at least one) feature made by the processing shaft and relative to the other marks.

In an embodiment, the apparatus comprises a control unit connected to the device for generating the synchronization signal, to the processing shaft and to the marking shaft. The control unit is configured to drive (control) the processing shaft and the marking shaft as a function of the synchronization signal. The control unit is preferably a central control unit of the line which comprises the apparatus. In other embodiments, the control unit is dedicated to the single apparatus (or machine).

In an embodiment, the processing shaft comprises a first embossing device, configured to apply a logo on a surface of the wrapping material.

In an embodiment, the processing shaft comprises a second embossing device, configured to make a knurled portion on a surface of the wrapping material.

In an embodiment, the marking shaft comprises an inkjet printing device. In an embodiment, the marking shaft comprises a laser engraving device. In an embodiment, the apparatus comprises a carbon tip positioning shaft. The carbon tip is positioned as a function of the synchronization signal.

In an embodiment, the apparatus comprises an illuminator configured to illuminate the mark on the wrapping material. The illuminator may be coupled to a mark detecting device.

This disclosure also provides a web of wrapping material used to make smoking articles.

According to the invention, the web comprises a logo. The logo is positioned on the outside surface of the wrapping material.

The web comprises a mark. The mark is applied on the inside surface of the wrapping material.

The web comprises a knurled portion. The knurled portion is preferably made on the outside surface of the wrapping material.

The web comprises a metallic element, made of metallic material (or including a metallic material). The metallic material is preferably aluminium. This element is positioned on the inside surface of the wrapping material.

This disclosure also provides a method for making smoking articles.

According to the invention, the method for making smoking articles comprises a step of feeding a web of wrapping material to a first machine. The web is advanced by a predetermined quantity corresponding to a length of a stretch of web used to make an article.

The method for making smoking articles comprises a step of making a feature (at least one) on the web of wrapping material. The feature is made by the first machine, specifically by a processing shaft of the first machine. The feature may be of the type described above with reference to the method for processing a web of wrapping material.

The method for making smoking articles comprises a step of applying a mark on a surface of the wrapping material (preferably the inside surface). The mark is applied by the first machine, specifically by a marking shaft of the first machine. The mark may be applied, for example, by inkjet printing or by laser engraving.

The method comprises a step of transferring the wrapping material from the first machine to a second machine.

The method comprises a step of cutting the web. By cutting, the web is divided into a plurality of connecting strips.

The method comprises a step of rolling each connecting strip of the plurality around a respective group of segments of the tobacco industry in such a way as to make a (continuous) rod. The step of rolling is preferably performed in the second machine. Each group of segments comprises at least one filter segment and one tobacco segment. Each group of segments may also comprise a carbon tip. The step of rolling is performed in such a way that the surface of the strip with the mark on it faces the inside of the rod.

The method comprises a step of cutting the web to divide it into a plurality of smoking articles. The step of cutting is preferably performed by a cutting tool disposed in the second machine.

The method comprises a step of detecting a position of the mark in the second machine. The step of detecting is preferably performed by an optical sensor (for example, a photocell).

Preferably, the step of detecting the mark is performed before the web is cut into connecting strips.

The steps of rolling and cutting are controlled as a function of the position of the mark detected.

In an embodiment, the method preferably comprises a plurality of steps of detecting the position of the mark in the second machine (at respective points in the second machine). The steps of rolling and cutting are controlled as a function of the position of the mark detected in one or more of the plurality of steps of detecting.

In an embodiment, one step of detecting of the plurality of steps of detecting is performed before the step of cutting the web. The step of cutting the web is controlled as a function of the position of the mark detected. In an embodiment, the step of cutting the web is performed by the second machine (that is, by a cutting device of the second machine).

For example, a first step of detecting the mark controls the step of cutting the web, a second step of detecting the mark controls the step of rolling and a third step of detecting the mark controls the step of cutting the rod.

The steps of feeding, of making a feature and of applying the mark are repeated cyclically with periodicity. In an embodiment, the method further comprises a step of generating a synchronization signal representing the periodicity. The mark is applied by means of a shaft (a marking shaft) controlled by the synchronization signal. In an embodiment, the process by which the feature is made on the web in the first machine is controlled by the synchronization signal.

In an embodiment, the step of cutting the web is performed by the first machine (that is, by a cutting device of the first machine) as a function of the synchronization signal.

According to the invention, the method comprises a step of temporarily storing a stretch of the web of wrapping material in a buffer. The buffer is preferably disposed downstream of the first machine and upstream of the second machine. In an embodiment, the step of transferring from the first machine to the second machine comprises the step of storing in the buffer.

According to the invention, the length of the stretch of web of wrapping material present in the buffer is variable over time.

This disclosure also provides a line for making smoking articles.

The line comprises at least a first machine and a second machine.

The line also comprises a buffer (between the first and the second machine).

In an embodiment, the first machine is an apparatus for processing a web of wrapping material according to one or more aspects of this disclosure. In an embodiment, the second machine comprises a cutting device for cutting the web of wrapping material and configured to divide the web into a plurality of connecting strips.

In an alternative embodiment, the cutting device for cutting the web of wrapping material, configured to divide the web into a plurality of connecting strips, might be built into the first machine or at an intermediate position, between the first ad the second machine.

In an embodiment, the second machine comprises a rolling device for rolling the connecting strips. The rolling device is configured to roll each connecting strip around a respective group of segments of the tobacco industry in order to make a rod. The connecting strips are rolled in such a way that the surface of each strip with the mark on it faces the inside of the rod.

In an embodiment, the second machine comprises a cutting device for cutting the rod and configured to divide the rod into a plurality of smoking articles.

The second machine further comprises at least one device for detecting the position of the mark. The detecting device is preferably an optical detector (for example, a photocell). The web cutting device, the rolling device and the rod cutting device are controlled as a function of the position of the mark.

The features of the invention will become more apparent from the following description of preferred, non-limiting embodiments of it, illustrated by way of example in the accompanying drawings, in which:.

With reference to the accompanying drawings, the numeral <NUM> denotes a line for making smoking articles <NUM>.

The line <NUM> comprises a feeding device <NUM> configured to feed a web of wrapping material <NUM>. Preferably, the feeding device <NUM> feeds the web <NUM> by unwinding it from a roll <NUM>.

The line <NUM> comprises a processing shaft <NUM> configured to create at least one feature on the web <NUM>.

The at least one feature on the web <NUM> may comprise a logo <NUM> on an outside surface 2B of the web of wrapping material <NUM>.

The at least one feature on the web <NUM> may comprise a metallic element <NUM> applied on an inside surface 2A of the web of wrapping material <NUM> (the surface intended to face the inside of the respective smoking article <NUM>). The metallic element is applied preferably longitudinally relative to a direction of feeding and advancing the web <NUM>. In an embodiment, the metallic element is applied transversely to a direction of feeding and advancing the web <NUM>. The at least one feature on the web <NUM> may comprise embossing a surface of the web of wrapping material <NUM> to make a knurled portion <NUM>.

The line <NUM> comprises a marking shaft <NUM> configured to apply a mark <NUM> on a surface of the wrapping material <NUM>. Preferably, the mark <NUM> is applied on the inside surface 2A of the wrapping material.

In an embodiment, the line <NUM> comprises a first detecting device <NUM>, located downstream of the processing shaft <NUM>. In an embodiment, the detecting device <NUM> is configured to detect that the at least one feature made by the processing shaft <NUM> is applied correctly. In an embodiment, the detecting device <NUM> is configured to detect at least one property of the at least one feature.

In an embodiment, the line <NUM> comprises a control unit <NUM>, configured to generate a synchronization signal (representing a periodicity, or cyclicity of the processes by which the features and marks are made). The control unit <NUM> drives the marking shaft <NUM> and the at least one processing shaft <NUM> as a function of the synchronization signal. In an embodiment, the web <NUM> is fed continuously while the mark <NUM> is being applied, and application is controlled by the synchronization signal as a function of the feeding of the web <NUM>.

In an embodiment, the control unit <NUM> is also configured to determine whether the feature meets at least one criterion of acceptability.

In an embodiment, the feeding device <NUM>, the processing shaft <NUM>, the marking shaft <NUM> and the first processing device <NUM> form part of a first machine (also referred to as apparatus for processing a web of wrapping material).

In an embodiment, the line <NUM> comprises a buffer B. The buffer B is of the "pendulum" or movable roller type.

The line <NUM> comprises conveyors <NUM>, <NUM> configured to feed a succession of groups. Each group comprises a filter segment <NUM> and a cigarette segment <NUM>. Each group may also comprise a carbon tip <NUM>. The groups are conveyed transversely to the web <NUM>.

The line <NUM> comprises a cutting device <NUM>. The cutting device <NUM> is located downstream of the marking shaft <NUM>. The cutting device <NUM> is configured to cut the web <NUM> into a plurality of connecting strips <NUM>.

The line <NUM> comprises a rolling bed <NUM> configured to receive the succession of groups and the plurality of connecting strips <NUM> and to roll the plurality of connecting strips <NUM> round the respective groups to make a rod. The line <NUM> comprises a second detecting device <NUM>, connected to the control unit <NUM>, and disposed downstream of the rolling bed <NUM>. The second detecting device <NUM> is configured to identify the articles <NUM> which are defective and to activate a procedure for these articles <NUM>.

In an embodiment, the line <NUM> comprises a rejection device <NUM> configured to reject the defective articles <NUM>.

Claim 1:
A method for processing a web of wrapping material (<NUM>) to make smoking articles (<NUM>), comprising the following steps, repeated cyclically with periodicity:
- feeding the web of wrapping material (<NUM>) to advance it by a predetermined quantity corresponding to a length of a stretch of web used to make an article (<NUM>);
- creating a feature on the web of wrapping material (<NUM>);
- applying a mark (<NUM>) on a surface of the web of wrapping material (<NUM>);
- generating a synchronization signal representing the periodicity, wherein the mark is applied by means of a shaft controlled by the synchronization signal, and wherein the step of creating the feature on the web of wrapping material (<NUM>) is controlled by the synchronization signal,
characterized in that the method comprises a step of temporarily storing a stretch of the web of wrapping material (<NUM>) in a buffer (B), the length of the stretch of the web of wrapping material (<NUM>) in the buffer (B) being variable over time.