FIELD OF THE INVENTION

The present invention relates to the technical sector concerning a method for printing images on flat articles of various dimensions, the articles being made of any printable material.

DESCRIPTION OF THE PRIOR ART

WO 2013/168076 describes a method for realising a component comprising a plurality of images, made available in a first file, the component having a flat extension and being made of a printable material, positioned on a work plane of a printing machine, managed and controlled by an electronic processor, there being arranged, above the plane, optical means for detecting the positioning of the component and the dimensions thereof; the method comprising:

processing, using the processor, a virtual representation of the component; circumscribing the profiles of the images of the first file with a same number of closed lines to define corresponding sets, constituted by images and relative closed lines, memorised in a second file;

carrying out, on the virtual representation of the component, a grouping of a plurality of the sets which are translated and rotated so as to minimise the surface of the component not circumscribed by the closed lines so as to define an intermediate file;

memorising the pagination of the intermediate file in a print file;

using the printing machine to print the images of the plurality of sets on the component.

In this way a component is obtained on which the sets are printed.

The solution provided by WO 2013/168076 does not enable defining an “overall image”, owing to the fact that the sets are not orientated in an ordered way on the component; in fact these sets are arranged so as to minimise the surface of the component not circumscribed by the closed lines relative to the images of the sets.

In order to obtain articles with a predetermined image, it is necessary to cut the component according to closed-loop paths, for example at or in proximity of the closed line which circumscribes each image: this undoubtedly constitutes a drawback.

SUMMARY OF THE INVENTION

The invention has the aim of providing a method for printing images on flat articles of various dimensions randomly positioned on a work plane of a printing machine, which obviates the drawback of the prior art.

A further aim of the invention is to provide a method that enables a virtual pre centring of the images on corresponding articles.

A further aim of the invention is to provide a method which enables minimising the time required for printing a plurality of articles of different sizes positioned on a work plane of the printing machine.

A still further aim of the invention is to provide a method for printing images on flat articles of various dimensions which enables“loading”, in the RIP (Raster Image Processor) software, a corresponding print file readable by a printing machine.

A further aim of the invention is to provide a method that as well as satisfying the preceding aim enables printing any article as long as it is made of a printable material.

The above-mentioned advantages of the invention are obtained according to the contents of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristics of the invention are specified in the following with particular reference to a preferred, but not exclusive, embodiment, with reference to the accompanying tables of drawings, in which:

- figure 1 schematically illustrates a block diagram of a method for printing images on flat articles of various dimensions, object of the present invention;

- figures 2A, 2B, 2C, schematically illustrate, and by way of example, in order, a series of images, a series of borders of articles and a series of the same articles following the combination between images and corresponding borders of articles;

- figure 3 schematically illustrates the acquiring of the dimensions and the positioning of a series of articles located on the work plane of a machine for printing predefined images on corresponding articles;

- figures 4A, 4B schematically illustrate two operating steps of the method of the invention;

- figure 5A schematically illustrates the above-described printing machine as well as the above-mentioned articles on which predefined images have been printed;

- figure 5B schematically illustrates the above-described printing machine as well as the above-mentioned articles on which predefined images have been printed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to figures 1 , 2A, a series of images which are to be printed they are indicated with (h _, l _2, l ₃ , _, ... I _n ), each of which must be printed on a corresponding article (Ai _, A _2, A ₃ ,...A _n, ); each image (h, l ₂ , l ₃ , ... I _n ) is made to correspond to a closed line (H) that circumscribes the image, to create an image file (F _| ), memorised in a processor (E), containing the images (h _, l _2, l ₃ , _, ... l _n ), to each of which the corresponding closed line (H) circumscribing it is associated. In a first variant, the closed line (H) of each image ( , l ₂ , l ₃ ,... l _n ) coincides with the border of the corresponding article (A^ A ₂ , A ₃ , A _n ); in a second variant, the closed line (H) of the image (l _x ) in part coincides with the border (C _x ) of the corresponding article, while in a third variant, the closed line (H) of the image (l _y ) is internal of the border (C _y ) of the corresponding article. Letters (Ci _, C _2, C ₃ ,... C _n ,) denote the borders of the series of corresponding articles (A^ A ₃ ,...A _n ) to define a border file (F _c ), memorised in the processor (E): a border (Ci _, C _2, C ₃ ,... C _n, ) corresponds to each article A ₃ ,...A _n ) which delimits the surface and shape thereof, and, internally of which, a predefined image (h _, l _2, l ₃ , _, ... l _n ) can be inscribed according to a biunivocal correspondence. The image file (F _| ) and the border file (F _c ), are transmitted to and memorised in a processor (E) so as to create a biunivocal correspondence, wherein the image ( ) will be associated to the border (Ci), wherein the image (l ₂ ) will be associated to the border (C ₂ ), and so on, the association being carried out for all of the“n” images and the“n” borders memorised in the processor (E).

Also included is use of an article file (F*) comprising a series of sets (F^ F _2, ... F _n ) with each set obtained by correlating, according to a biunivocal correspondence, each image (l^ l ₂ , _, ... l _n ) to the corresponding border (Ci _, C ₂ , .. C _n ).

The proposed method relates to obtaining articles having a flat extension of printable material, for example cardboard, based on yarns, fabrics, plastic elements, sheets, rigid components, etc.

A series of articles (Ai _, A _2, A ₃ ,...A„) to be printed (figure 3) are positioned at random on the work plane (10) of a printing machine (1), each of which has a surface and a predefined profile.

An optical reader (L), located above the work plane (10) of the printer (1), detects the profile (dimension and border) of all the articles positioned on the work plane (10), the position and orientation of the articles with respect to the work plane (10); this representation is transmitted to the processor (E), and virtually displayed on the monitor (M) thereof (figure 4A).

Following this display, the processor (E), by means of an appropriate program, carries out the comparison of each article (A ₁ A ₂ A ₃ ,...A _n ), detected with the borders (Ci _, C _2, C ₃ , ... C _n ), memorised in the border file (F _c ) for the recognition of each type of article positioned on the work plane (10); subsequently the relative image (l^ l ₂ l ₃ , _, ... l _n ) is identified, memorised in the image file (F _| ) to be associated to each identified article, in order to proceed, according to the image file (F _| ) and border file (F _c ), with the orientation and the virtual centring of each image (l^ l ₂ l ₃ , _, ... l _n ) on and with respect to the virtual orientation of each article detected (A ₁ A _2, A ₃ , ...A _n ).

In a case in which the information of the image file (F _| ) and the article file (F _c ) are incorporated in the article file (F*), the step of virtual orientating and centring the image of the images (h , l ₂ , ... l _n ) with respect to the relative articles (Ai _, A _{2 ..} A _n ) is carried out according to the article file (F ^* ).

To define a virtual intermediate file (V*) in which the positioning and the orientation of the articles (A^ A ₂ , A ₃ , ...A _n ) on and with respect to the work plane (10) is identified, with the virtual association of the images (l^ l _2, l _{3 ,} ... I _n ) to the corresponding borders (Ci _, C _2, C ₃ , ... C _n ) conforming to the detected articles (A ₁ A _2, A ₃ , ...A _n ) to be printed (figure 4B).

The intermediate file (V*) is loaded in an RIP (Raster Image Processor) software of known type which processes the print layout: the RIP and the driver of the printer (1) (figure 5A).

Alternatively the virtual intermediate file (V*) is created by an operator, who following the display on the monitor (M) of the positioning, orientation and profile of the article, using known devices (mouse (S)), selects the image ( _, l _2, l ₃ , _, ... l _n ) corresponding to the displayed article and proceeds with the orientation and virtual centring thereof on the corresponding detected article. Following the creation of the intermediate file (V*), obtained automatically or manually, the printing head (2) of the printer (1), managed by the RIP, is activated to position itself where the articles to be printed are located in order to print the images corresponding to each determined article (Ai _, A _2, A ₃ , ...A„): see figures 5A, 5B.

The proposed method is particularly advantageous, as it enables printing images on flat articles of various dimensions and conformations, positioned on a work plane of a printing machine in a random order.

The method enables rapid identification of the type/s of article/s positioned on the work plane of the printer; it is in fact sufficient to memorise, in the processor (E), a series of images, a series of borders corresponding to a series of articles to be printed, a biunivocal correspondence between each of the images and a corresponding border and, following the detection of the optical reader (L), to draw from the memorised data to recognise the article/s. The fact of memorising a series of images delimited by a closed line (H) and the fact of memorising a series of borders corresponding to the profile and the dimensions of the article to be printed are advantageous.

Each image, corresponding to the border of the article to be printed, is virtually connected to what is detected by the optical reader (L); each image, in fact, corresponding to the article to be printed, is virtually orientated on the monitor (M) of the processor (E), as a function of the orientation of each article detected on the work plane (10), to identify the article file (F*), then to control the printing head (2), according to the coordinates referring to a Cartesian reference system with an origin coinciding with the origin of the work plane (10) on which the article is laid out, in order then to print on the article/s resting on the work plane (10).

The method of the invention advantageously enables a user to randomly and contemporaneously position, on the work plane of a printer, a series of articles having an identical format, or a different format: thus the print operation of a series of different articles is made more rapid.

The method enables optimising the potentiality of the printing machine, making it very versatile; in fact, as well as contemporaneously printing a plurality of different articles, between one print and another it is possible to vary both the number of articles to be printed, and the type thereof, and when necessary, integrating, according to a biunivocal correspondence, new images, new borders of corresponding new articles to be printed.

The virtual positioning of the images can be carried out automatically by the processor (E), or as previously described by an operator who, following the recognition of the article to be printed, performs the centring and the virtual orientation of the image corresponding to the identified article on the monitor (M).

It is stressed that the aesthetic appearance of each article (A ₁ A _2,.. A _n ) following the printing thereon of the relative images (l^ l ₂ ,... l _n ) is the predetermined one; in fact, not only the corresponding image is printed on each article, but also the image is arranged (for example centred) with respect to the border of the article according to predetermined modes.

This arrangement is a function of the dimensions and positioning of the line (H) which circumscribes the relative image (h _, l _2, ... l _n ) with respect to the corresponding border (Ci _, C _2,.. C _n ).

This is highlighted in figures 2A, 2B, 2C, wherein:

- the closed line (H) coincides with the border (images l ₂ l ₃ ,... l _n , borders Ci _, C _2„ C ₃ , _, ... C _n , sets F F ₂ F ₃ , ... F _n ); in these cases the image is centred with respect to the border;

- the closed line (H) is contained by the relative border: (image l _x rectangular, border (C _x ) rectangular, set (F _x ) in which two consecutive sides of (l _x ) are superposed on two consecutive sides of (C _x ); in this case the image is staggered with respect to the border; image l _Y , of varied profile, border (C _Y ) of varied profile, set (F _Y ) in which the image (l _Y ) is inside the border (C _Y ); in this case too the image is centred with respect to the border. In the latter case it is possible, where required, to decentre the image (l _Y ) with respect to the centre of the border (C _Y ).

Definitively, the closed line (H) that circumscribes the relative image (h _, l _2, ... l _n ) identifies a perimeter that is used to arranged the relative image with respect to the border (Ci _, C _2,.. C _n ) of the corresponding article (Ai _, A _2„. A„), for example centred, offset or decentred with respect to the centre of the border.

It is understood that the above has been described by way of non-limiting example and that any modifications of detail, and variants of form and dimensions of the described elements, and any technical-functional variants of the method steps are understood to fall within the protective scope, as claimed in the following.