Abstract:
Device to reproduce images or graphical patterns in general on large surfaces, comprising at least a printing system ( 14 ) mobile in at least one direction with respect to a support frame ( 12 )&gt;&gt; an optical viewing system ( 100 ) associated with the support frame ( 12 ) and able to recognize the position of the portion of image already executed, and to recognize possible reference signs affixed in the step when said portion of image was executed, in order to allow the correct positioning of the device so as to execute the adjacent portion of image that has to be executed next.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a 35 U.S.C. §371 National Phase conversion of PCT/IB2012/000929, filed May 11, 2012, which claims benefit of Italian Application No. UD2011A000072, filed May 13, 2011, the disclosure of which is incorporated herein by reference. The PCT International Application was published in the English language. 
     FIELD OF THE INVENTION 
     The present invention concerns a device and the corresponding method to reproduce images or graphical patterns in general, on large surfaces such as, but not only, walls, canvases or other surfaces, irrespective of their orientation. 
     The invention is applied particularly, although not exclusively, in the decoration of rooms, the facades of buildings, vehicles, and floors, in order to make indications, in restoration works etc., substantially on surfaces of any material, such as plastered walls, brickwork, plastic, glass, ceramics and tiles, metal, wood, etc. 
     BACKGROUND OF THE INVENTION 
     The complexities of reproducing graphical patterns are generally known, such as images, writings, copies of photographs, paintings, landscapes, decorations etc., in order to embellish and personalize a surface, for example an external or internal wall of a building, a fabric, a canvas, etc. 
     Manual solutions are closely connected to individual abilities and are lacking in repeatability and constant results. 
     In the state of the art partly automated solutions have been proposed, which use printing systems moved by a movement apparatus commanded by a computerized control unit. 
     For example apparatuses are known consisting of Cartesian type structures, for example a frame with movement on the x axis and y axis, which move a printing system, for example the paint gun type, with an ink jet head, a laser head or other, along the surface to be painted. 
     One disadvantage of known solutions derives from the fact that the bearing structure of the apparatus is not moved during the printing step of all the programmed and desired image. 
     Therefore, these solutions are satisfactory when the image to be reproduced is the same size as or smaller than the machine used, but they are not so if the size of the image is larger than the machine; alternatively, the apparatuses are complex and bulky if they have sizes comparable to those of the image. 
     One purpose of the present invention is to supply a device and a method to reproduce images, writings, decorations or graphical patterns in general on very large surfaces, using apparatuses of limited sizes, thus simplifying transport and use in restricted spaces, or which are difficult to reach. 
     Another purpose is to guarantee that the images reproduced are high quality, repeatable, with continuity in the lines and graphical patterns, with imperceptible joints between the various portions, in short times and at reasonable costs, and that this can be done easily and practically even by people who are not particularly expert. 
     The Applicants have devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages. 
     SUMMARY OF THE INVENTION 
     In accordance with the above purposes, the invention provides a method in which the area to be decorated, painted or otherwise embellished or enhanced, is divided into a plurality of consecutive sub-areas, to each of which is assigned a precise portion of the image or graphical pattern to be reproduced. 
     The invention also provides that, after the reproduction of the image has been completed in a first of the areas, the printing instrument is repositioned on each occasion in an adjacent position, without needing to carry out measurements or observations by the operator and without needing any positioning by the operator, and in any case the absolute continuity and precision between the adjacent portions of image reproduced one after the other is guaranteed. 
     According to one form of embodiment of the present invention, the device used in the above method comprises a printing system, for example a print head, a paint gun system or other system, which may be one known in the state of the art, mounted on a support frame which allows it to be moved on a plane. 
     The support frame has variable dimensions according to need but, in the spirit of the invention, it is not bulky but easy to transport, assemble and store. In one solution of the invention, the support frame is square or rectangular with sides between 30 and 100 centimeters. 
     In a first solution, the device is suitable to be used manually, kept by the operator in a position facing the surface to be decorated at a suitable distance so that the printing system can make the decoration. 
     According to a variant, the device can be associated with a support system, for example a tripod, a base, a pole or suchlike, also of the self-moving type. 
     According to the invention, the support frame allows movement of the printing system along at least two axes, for example axes x and y of a Cartesian plane. 
     In order to carry out this movement, there are at least two systems with a motorized drive, one for each axis of movement, by means of which the printing system is correctly positioned to perform the programmed printing. 
     The device according to the invention is also equipped with an optical viewing system, for example with one or more cameras, or LED or laser devices associated with corresponding electro-optical transducers. 
     The optical system for example allows recognition of the position of the portion of the image already done, and recognition of possible reference signs affixed on the wall, canvas or other surface to be decorated in the execution of said portion of the image, in order to allow the correct positioning of the device so as to execute the adjacent portion of the image which is to be done next. 
     The subsequent positioning of the whole device can be carried out manually by the operator, to the position where the optical system indicates that the reference signs have been recognized and signals to the operator for example to rest the device on the wall in order to execute the next portion of image; in variant embodiments, the positioning of the device is governed by a system for moving the possible support on which the device is mounted. 
     In one form of embodiment of the invention, the device also comprises a device for detecting the inclination, associated for example with the support frame, which detects if the frame is correctly positioned with respect to the wall to be decorated, before starting printing and/or during printing, and possibly corrects the position and drive of the printing system to guarantee that the portion of image is correctly oriented even in the presence of a support frame that is not correctly positioned. 
     According to the present invention, the device is associated with a command and control unit which regulates and manages the functioning thereof. The command and control unit comprises at least a memory containing an archive of a plurality of images, decorations, designs, landscapes and graphical patterns in general, which a user can access in order to select the graphical pattern to be reproduced. 
     The command and control unit may comprise, or be associated with, a unit for acquiring images, for example a scanner, a camera or other suitable device, to acquire an image which then, suitably sized, for example enlarged, can be reproduced on the surface to be decorated. 
     The command and control unit may also comprise a command interface with which an operator can not only select from the archive the image to be reproduced, but can also modify it, for example inserting writings or suchlike, or he can combine together two or more images, or process a selected image as desired. 
     The command and control unit is also connected to the support frame of the printing system to determine the movement thereof on the Cartesian axes according to the image to be printed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein: 
         FIG. 1  shows a rear view of the device according to the present invention according to one form of embodiment; 
         FIG. 2  shows a section of the device in  FIG. 1  from A to A; 
         FIG. 3  shows the detail of the printing system of the device in  FIG. 1 ; 
         FIGS. 4   a ,  4   b,    4   c  and  4   d  show a sequence of the decoration steps of a wall using the present invention. 
     
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     A device to reproduce images  10 , as shown in  FIGS. 1 and 2 , comprises a bearing frame  12 , in this case square, with sides equal to about 50 cm. In one solution that is not shown here, the bearing frame  12  may have feet or little suckers, or a similar feature to facilitate its resting on the wall to be decorated by the operator, and also to increase its stability during use. 
     It is obvious that both the shape and sizes of the device  10  shown in the drawings are merely indicative; the sizes may change, although the device remains configured for a mainly manual use, so that its sizes and weight allow it to be kept in position by an operator, also during use. 
     The device  10  shown in the drawings in this case comprises a print head  14  that can move in the bearing frame, in a vertical direction “y”, along a first guide  16 . 
     Here and hereafter in the description the directions vertical and horizontal refer to the representation in  FIG. 1 , although it is obvious that the device  10  can be used with any orientation, also with the sides inclined with respect to a horizontal or vertical direction. 
     The print head  14  is passed through by a worm screw  18  which, at both ends, is connected to a corresponding support  20 ; the supports  20  support the print head  14  and allow it to rotate. The supports  20  are both connected to a belt  22  (as shown in  FIG. 1 ) which allows them to move along a second guide  24  in a horizontal direction “x”. 
     The movement in the vertical direction of the print head  14  is generated by the fact that the worm screw  18  can rotate in one direction or the other, the rotational movement being determined by a first drive means  26  that is disposed inside one of the two supports  20 , in this case the lower one. 
     To make the two belts  22  rotate, one of which is located in a first horizontal side and the other in the opposite horizontal side of the frame  12 , in order to impart the horizontal movements to the support frame  12 , a second drive means  28  is used, connected to a support  30  that transmits the rotation of the second drive means  28  to the two belts  22 . 
     The functioning of the first drive means  26  and the second drive means  28  is managed by a control unit  40  (shown in  FIG. 4   a ), which is connected to the device  10  by means of a cable  32 . It comes within the field of the invention that the device  10  may be connected to the control unit by means of a wireless connection, Bluetooth or any other type of wireless connection. 
     To determine the inclination of the device  10  for a possible correction of the orientation of the image to be painted by the control unit, on one side of the frame  12  there is a three-axis accelerometer  34 . 
     Obviously, it comes within the field of the invention that one or more accelerometers  34  may be disposed on one or more corresponding sides of the support frame  12 . 
     The print head  14 , as shown in  FIG. 3 , consists of nozzles  102  (for example five: cyan, magenta, yellow, white and black) with corresponding cartridges to paint the wall  200  with the portion of image, and of an optical detection system  100 , which is used in the movements of the device  10  to determine, by the control unit  40 , at least the position of one or more portions already produced, and thus to determine the point from where the painting of the wall  200  is to be restarted. 
     In one form of embodiment shown in  FIG. 2 , the device  10  has two handles  36  associated with the frame  12  of the device  10 , to allow manual use by an operator. 
     The device  10  can also be bigger, and therefore not able to be easily held manually by the operator, or at least for the period required to complete a respective portion of image; in this case, one form of embodiment of the invention provides that the support frame  12  is mounted on a self-moving support  208  (shown by dashes in  FIG. 4   a ) and the painting operations in this case can be carried out at least partly without the operator. 
     The device  10  as described heretofore functions as follows. 
       FIG. 4   d  shows a wall completely painted with an image  202  that is to be obtained by repeating a decorative element  204  both vertically “y” and horizontally “x”. 
       FIG. 4   a  shows the first step of the method to paint the wall  200  using the device  10  where the image  202  to be reproduced is divided into different sequential portions, respectively  206   a ,  206   b ,  206   c ,  206   d . The device  10  is positioned, either manually by the operator using the two handles  36 , or using a self-moving device  208  which supports the device  10 , in correspondence with the upper left edge from where the reproduction of the first portion of image  206   a  on the wall  200  is to start. 
     The device  10  starts painting the first portion of image moving the print head  14  in both a horizontal direction “x” and in a vertical direction “y” along the whole length of the device  10 . 
     In correspondence with the horizontal end of the first portion of image  206   a  with which subsequently a second portion of image  206   b  will be placed laterally adjacent, the device  10  will trace a vertical edge  210   a  which will subsequently be used to recognize the portion of image already painted. In correspondence with the vertical end of the first portion of image  206   a  with which subsequently another portion of image  206   c  will be placed vertically adjacent, the device  10  will trace a horizontal edge  210   b  (as shown in  FIG. 4   b ) which will subsequently be used to recognize the portion of image already painted. 
     In  FIG. 4   b  the device  10  has finished painting the first portion of image  206   a , in which the corresponding edges  210   a ,  210   b  are shown, continuous with the subsequent portions of image which have to be made subsequently. The device  10  can therefore be moved toward the subsequent portion of the image. As shown in  FIG. 4   b , the device  10  is moved laterally so that it can reproduce the portion of image  206   b  which is on the right of the portion of image  206   a  already done. To determine the position from where painting is restarted, the device  10  uses the detection system  100  mounted inside the print head  14 , to analyze the position of the vertical edge  210   a  which has already been done. 
     As shown in  FIG. 4   c , once the position of the edge  210   a  has been determined, the device  10  starts painting the second portion of image  206   b  with the same characteristics and method as described before. The edge  210   a , having been painted with a shade of color compatible with the portion of image  206   b , will be totally covered by the painting of the portion of image  206   b , in this way giving the idea of continuity of the image  202 . 
     It is clear that modifications and/or additions of parts may be made to the device to reproduce images  10  as described heretofore, without departing from the field and scope of the present invention. 
     For example, it comes within the field of the invention that, instead of the printing system with nozzles as described heretofore, laser engraving heads may be used, milling, or even dispensers of gluing substances, for example to apply materials such as wall paper or decorations in general according to particular graphical patterns. 
     It is clear that instead of tracing a specific edge, such as  210   a  as previously described, any reference sign whatsoever, or part of an image, can be used as a reference. 
     It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of device to reproduce images  10 , having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.