MXPA96001532A - Liquid ink printer transport belt cleaner - Google Patents

Abstract

A cleaning apparatus for cleaning a transport belt in a printing machine of the type in which liquid ink is deposited on a recording medium moved along a path by the transport belt. The cleaning apparatus located next to the transport belt cleans a first surface and a second surface of the transport belt when ink and/or other contaminants collect on the belt. A sensor senses when the belt needs cleaning. Interior side walls of apertures within the belt which enable vacuum transport of the recording medium through the printing machine are also cleaned.

Description

_i * CONVEYOR BAND CLEANER FOR A LIQUID INK PRINTER FIELD OF THE INVENTION This invention relates generally to the printing on a liquid ink printer and more particularly to the cleaning of a conveyor belt or conveyor that transports the engraving or printing ink through the printer during printing.

BACKGROUND OF THE INVENTION Liquid ink printers of the type often referred to as drop-on-demand or drop-on-demand, such as acoustic or piezoelectric phase shifts based on waxes or thermals, which have at least one print head which drips the ink that is directed towards the engraving or printing sheet. Within the print head, the ink is contained in a plurality of channels. The power pulses cause the ink droplets to be ejected as required from the holes or injectors at the end of the channels. Continuous ink flow printers are also known. In a thermal inkjet printout, the power pulses are usually produced by resistors, each located in one of the respective channels, which are individually designed to heat and vaporize the ink in the channels. As the voltage is applied through a selected resistor, a vapor bubble grows in this particular channel and the ink protrudes or bulges in the channel orifice. In this stage, the bubble begins to collapse. The ink within the channel reacts and separates from the ink that protrudes or bulges such that it forms a droplet moving away from the channel orifice and towards the engraving or printing medium upon which a spot is formed. reaching or hitting the print or print medium. The channel is then refilled by capillary action, which, in turn, ejects ink from a liquid ink management container. The operation of an inkjet printer is described, for example, in U.S. Patent No. 4,849,774. The ink jet print head can be legally constituted in either a type of carriage printer or a type of printer of the width of the page. The cart type printer typically has a relatively small print head that contains ink channels and nozzles. The print head can be sealedly attached to a disposable ink supply cartridge and the assembly or assembly of the combined cartridge and printhead are attached to a carriage corresponding to the printing of a row of information (equal to the length of a column of the injectors), at one time, on a stationary printing or etching medium, such as paper or a transparency. After the row is printed, the paper is staggered a distance equal to the height of the printed row or a portion thereof, such that the next printed row is contiguous or superimposed superimposed. The procedure is repeated until the entire page is printed. In contrast, the page width printer includes a stationary printhead having a length equal to or greater than the width or length of a sheet of the printing or engraving medium. The paper is continuously moved past the print head of the width of the page in a direction normal to substantially the length of the print head and at a constant or variable speed during the printing process. Flatbed inkjet printers are described, for example, in US Patent No. 5, 192, 959. It has been recognized that there is a need to maintain ink jet nozzles of print heads of liquid ink such as an ink jet print head, periodic cleaning of the holes when the print head is in use by purging or vacuum removal of the ink and / or covering the print head when the printer is out of service or inactive for long periods of time. The cover of the print head has the purpose of preventing the drying of the ink in the printhead. There is also a need to prepare or purge the print head nozzles before use and occasionally during use to ensure that the print head channels are completely filled with ink, and that they do not contain contaminants or air bubbles, and that they do not dry out due to not being used. Typically, the ink jet print head moves in position or vice versa with a preparation and / or maintenance station for the print heads of the ink jet printers. In a flatbed print head, maintenance of the nozzles across the total length of the print head is especially critical since not all individual injections can be discharged during the printing of a single sheet of paper or over several sheets of paper. Occasionally, the ink can be collected on the belt or conveyor belt during the bleeding of the print head nozzles, during the usual maintenance of the print head, or during the same printing if a paper and ink acquisition occurs. it is deposited on the belt or conveyor belt instead of the engraving or printing medium. Consequently, this situation arises when a liquid ink printer is designed for the effective control of any unwanted deposit of ink on the belt or conveyor belt. Consistently, it is desired to clean the belt or conveyor belt of the ink and / or other contaminants before the printing resumes, since the ink deposited on the tape or band may otherwise ruin the printed or printed print medium. perfectly. Various cleaning mechanisms for cleaning tapes or bands and other devices present in printing machines are illustrated and described in the following statements that may be relevant to certain aspects of the present invention. In US Pat. No. 3,867,170 according to Ferguson et al., A method for cleaning by liquid developers of the image surface of an imaging system is described. The image surface is cleaned with a cleaning liquid that is miscible with the liquid developer. A cleaning cloth absorbs the cleaning liquid and comes into contact with the image surface to dilute and dissolve the liquid developer. US Pat. No. 4,568,174, according to Strange, describes a photoreceptor device for cleaning contaminants from a surface f or t r r e c e p t o r a. The device includes a flexible fabric that moves in engagement or union with the receiving surface.

BRIEF DESCRIPTION OF THE INVENTION In accordance with one aspect of the present invention, there is provided a printing machine of the type in which the liquid ink is deposited on a recording or printing medium moving along a path. The printing machine includes a belt or conveyor belt that moves the engraving or printing medium along the path, a sensor or detector is placed next to the belt or conveyor belt and detects contaminants on the belt or conveyor belt. A cleaning apparatus is placed next to the conveyor belt and cleans the belt or conveyor belt in response to the sensor or detector detecting the contaminants on the belt or conveyor belt Other aspects of the present invention will become apparent when the following description proceeds and which is guided with reference to the drawings, wherein: BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic side elevation view of an embodiment of an ink jet printer that is incorporated in the present invention. FIG. 2 is a schematic perspective view of a belt or conveyor belt, the detecting apparatus and the cleaning apparatus of the present invention of a mode.

FIG. 3 is a schematic side view of one embodiment of the cleaning apparatus of the present invention. While the present invention will be described in conjunction with a preferred embodiment thereof it should be understood that it does not intend to limit the invention to this modality. By the intent, it is intended to cover all alternatives, modifications, and equivalents that may be included. within the spirit and scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES FIG. 1 illustrates a schematic side elevational view of an inkjet printer 10. The inkjet printer 10 includes an input tray (not shown) containing sawed sheets from the paper store or transparencies for printing. The individual engraved printing sheets are extracted from the input tray and fed into the conveyor belt 12 driven by means of the rollers 14 below a printing member 16. The belt or conveyor belt 12 is substantially transparent to the microwave energy and includes a plurality of openings 15 (see FIG 2), with a height equal to the thickness of the belt or strip 12, having inner walls through the which a vacuum is applied to hold the printing sheet to the band or tape as it moves through the printer. Suitable materials include ULTEM, a polyurethane, available from General Electric, KALADEX, a polyethylene naphthalate, available from Imperial Chemical Industries (ICI) of Wilmington, Dela, and other materials having a low dielectric strength. that can be formed in a tape or band. The printing member 16 includes one or more inkjet printheads in the page width deposited by the liquid ink on a sheet of paper or transparency or other printing medium when the tape or band 12 carries the engraving sheet or printing beyond the printing member 16.

As illustrated, the printing member 16 includes four print bars across the width of the page for the complete printing of color images comprising cyan, magenta, yellow, and black. Each of the inkjet print bars for the width of the sheet includes a linear array of print nozzles in such a way that the ink is deposited across the width or length of the sheet. However, the present invention is equally applicable to printers having an ink jet print head or print heads that move through the sheet periodically in rows, to form the image, and for printers that have staggered arrays of print heads or for printers that have a simple print bar. The printing member 16 includes an ink supply that can either: be located with the same print head or can be located elsewhere and connected to the print head through an ink duct. In addition to an ink supply, the printing member 16 includes the necessary electronic elements to control the deposition of the ink on the individual sheets. During printing, a recording or recording sheet 17 is affixed to the conveyor belt 12 through a printing area 18, by means of an applied vacuum of a first vacuum applicator 20. A region between the documents 21 locates between the recording or recording sheets 17 in areas where the conveyor belt or belt 12 is not in contact with the engraving or printing sheets 17. Once printed, the engraving or printing sheet 17 enters into a inlet slot 22 and exits in an outlet slot 24 of a dryer 26. The dryer 26 has attached * in addition a second vacuum applicator 28 for additional applications of a vacuum to the recording or recording sheet 17 through the tape or band 12 when it traverses through the dryer 26 in the direction of the process of an arrow 30. The conveyor belt or belt allows the use of simple transport for either printing or for image formation and drying. It is also possible that a simple vacuum applicator can be used both in the printing or imaging region 18 and the dryer 26. Once the liquid ink has been dried by means of the dryer 26, it exits through the outlet slot 24 and is deposited in an output tray (not shown). The controller 32 controls the printing member 16, the dryer 26, and the rollers 14, as one skilled in the art should understand. In addition, a control for the adaptive dryer can also be used to control the speed of the tape or web 12 through the dryer 26. US Patent No. 5,214,442 entitled "Control for the Adaptable Dryer for Ink Jet Processors. ", assigned to Xerox Corporation, describes a control for the adaptive dryer and is also incorporated herein by reference. In the present embodiment of the invention, the dryer 26 includes a microwave dryer that applies microwave power to dry the ink deposited on the recording or printing sheet 17. A microwave dryer suitable for use in the present invention is described in FIG. US Patent Application No. 08/159, 908 entitled "Apparatus and Method for Ink Drying Deposited by the Inkjet Printer" for Xerox Corporation and filed on November 30, 1993, the relevant portions are incorporated herein as a reference. Since a microwave dryer is used, inks specially formulated to absorb microwave power are preferred. Such inks can include compounds designed to bind with microwave power to increase the amount of heat conducted. Such a compound is an ionic compound, at least ionizable in the liquid vehicle. U.S. Patent No. 5,220,346 entitled "Microwave Drying Printing Processes", issued to Xerox Corporation, discloses a suitable ink and is in part incorporated in this application by way of reference. During operation of the ink jet printer 10, contaminants, such as ink or other ink or debris, can be collected on a surface 34 of the tape or band 12 instead of being collected on the printing or engraving medium. due to the malfunctioning of the printer 10, such as the paper capping, the ink deposit in the regions between the documents, and the misdirected injectors that could potentially deposit ink on the belt or band. The presence of ink on the tape or band causes few significant problems. A contaminated tape or band of ink quickly becomes damaged when the microwave dryer overheats the areas where the ink has been deposited. The tape or band gets deformed in these areas, since the ink acts as a drop in temperature, thereby overheating the tape or band. In these areas the tape or band does not remain perfectly flat or stretched and consequently the engraving or printing medium does not remain perfectly flat in substantial form which is necessary for the printing itself. As the printing or recording medium passes under the printing bar, the throat between the printing bar and the printing or engraving medium is not maintained any longer. The loss of the appropriate throat not only degrades the image that is printed, but the tape or deformed band causes the printing or engraving medium to contact the print head, the ink stains, thereby spoiling the image and further contaminating the tape or band In addition, since the tape or band 12 includes the plurality of apertures 15, the ink deposited on the surface of the tape or band that contacts the recording or recording sheet 17 can be oolected on the inner side walls of the apertures of the film. the tape or band and still a surface 36 of the tape or band by means of movement through the openings. Accordingly, the present invention provides an apparatus for detecting ink on both sides of the belt or band and an apparatus for extracting contaminants and / or cleaning both sides of the belt or band. As illustrated in FIG. 1, the present invention includes a detection apparatus 40 having a first detector arrangement 42 for the detection of ink or other contaminants that may be deposited or found on the surface 34 of the tape or band 12 and a second detector arrangement 44 for the detection of the surface 36 to determine both the ink or contaminants that have been deposited therein. The detection apparatus 40 is attached to the controller 32 which receives the signals from the detector apparatus 40 which indicates that one or both surfaces of the belt or band 12 have become contaminated. It is well known and common to program and execute controllers for printing, document detection and / or control functions for paper handling and logic circuits with instructions for controllers with conventional or general purposes that include microprocessors. This is shown in several previous patents and commercial products. Such programming or data processor can, of course, vary depending on the particular functions, type of the data processor, and microprocessors or other computer systems used, but they must be available for, or quickly programmable without undue experimentation of, functional descriptions. , such as those provided here, or prior knowledge of functions are conventional, along with general knowledge in the techniques of computing data processors. This may include objects oriented to data processor development environments, such as C ++. Alternatively, the described methods or systems can be partially or fully implemented in processors, using standard logic circuits or a simple integrated circuit or chip using VLSI designs. The detector apparatus 40 may include any number of known detection devices for the detection of contaminants or other unwanted materials such as an infrared densimeter, reflective sensors, or light source / photodiode sensors. An acceptable sensing device is described in US Patent No. 4,967,238 according to Bares et al. For Xerox Corporation, which has the title "Monitor for Cleaning Performance", the relevant portions of which are incorporated by reference. The type of sensing device depends on the materials that are detected and the material of the tape or band. Upon request, if the band or tape 12 is made of a material that is light transmitter, such as KALADEX, the first detection array 42 could be a linear array of photodiodes and the second detector array could be a linear light source for the transmission of light through the band or tape to the first detector array 42. When the ink or other contaminants block the transmission of light through the band or tape, the detector apparatus 40 will indicate that the band or tape needs to be cleaned. In addition, if a light transmitting material is used for the band or tape 12, it is possible that a reflective sensor located on only one side of the band or tape may be sufficient to detect the presence of ink since the ink reflects any light to be transmitted from it and therefore the reflective sensor could detect ink on the first surface of the band or tape or the second surface of the band or tape. Once the ink is detected by the detector apparatus 40, the controller 32, which receives a signal from the sensor apparatus indicating that the ink is. contaminating the band or tape, sends a signal to the cleaning apparatus 50 which then cleans both sides of the tape or band 12. The cleaning apparatus 50 includes a first cleaning device 52 and a second cleaning device 54. The first device of cleaning 52 is used to clean the cleaning surface 36 of the tape or band 12. The second cleaning device 54 cleans the opposite surface 34 of the band or tape 12. FIG. 2 illustrates the tape or band 12 that includes the plural i. openings 15, the detector apparatus 40 and the cleaning apparatus 50. While FIG. 2 shows a location for the sensing apparatus 40 and for the cleaning apparatus 50 with respect to the belt or band, the location illustrated is not limited and other locations for the detector apparatus 40 and cleaning apparatus 50 are possible. FIG. 3 illustrates a schematic side view of one embodiment of the cleaning apparatus of the present invention. The first cleaning apparatus 52 includes a cleaning cloth 60 that moves in the direction of an arrow 62 that is opposite to the direction of movement 30 of the tape or band 12. The cleaning cloth 60 advances from a supply roll 64 around of a first roller with guide pulley 66, a second roller with guide pulley 68 and on a contraction roller 70. When ink or other contaminants are detected by means of detector apparatus 40, controller 32 receives a signal from the apparatus detector 40 indicating that the belt or band needs to be cleaned, and controls an engine 72 for advancing the shrink roll 70. In addition, the first cleaning device 52 moves in contact with the belt or band 12 by means of the movement of the first detector device 52 in the direction of arrow 74 as known to those skilled in the art. In addition to controlling the advancement of the shrink roll 70, the controller 32 also controls the supply of the cleaning fluid for a pump 76 having an array of injectors 78 for depositing a cleaning fluid 80 on the interior surface of the fabric 60. The pump 76, the arrangement of injectors 78, as well as the cleaning cloth 60, have a dimension that is sufficiently wide to cross the total width of the belt or band 12 for cleaning the surface 34 thereof. A supply of fluid 82 supplies the cleaning fluid when it is necessary for the pump 76 by wetting the fabric 60. The effective application in particular of the cleaning liquid to the belt or band 12 is obtained with a fabric consisting of fibrous materials highly absorbent While highly absorbent fibrous materials may be employed in the configuration of the ends of the braided wick or wicks, the cleaning materials are preferably in the form of continuous fabrics to facilitate the replenishment of the new cleaning liquid for the fabric. Since the material of the fibrous web functions as a liquid cleaning applicator for the belt or band 12 and can also function as an absorbent sheet for the extraction of ink, contaminants and any liquid applied to the belt or band 12, the material of The fibrous web must have sufficient moisture resistance to prevent tearing or splitting when; moistens by the cleaning liquid. The fibrous material is preferably softer than the band or tape 12 such that it does not wear the band or tape; it is free of threads or yarns; and it is not chemically reactive with the surface of the tape or band. Also, the material of the fabric preferably does not contain any soluble that can be dissolved in the cleaning liquid or cleaning system and that has adequate absorption capacity to absorb the liquid residue that results from the immersion or staining of the residual ink and the cleaning liquid on the tape or band. The important characteristics of the fibrous material, however, are the ability to transmit cleaning liquid from the cleaning liquid supplier to the belt or band 12 and a good absorption and retention of the ink or contaminants after the cleaning has been carried out. Further, since the belt or band 12 includes a plurality of openings having inner walls, the material of the fabric must have a sufficient amount of fluff or fluff so that the material of the fabric can clean the inner walls of the openings . The fleece should be thick enough so that the fabric thoroughly cleans the interior walls of the openings so that both fabrics cooperate to clean it. Any suitable fibrous material can be used. Typical fibrous cleaning materials include those made of ordinary cloth, flannel, rayon, cotton, dacron, polyester fibers, polypropylene fibers, cellulosic and paper fibers, nylon, rayon and cotton combinations, and mixtures thereof. . In particular, satisfactory cleaning is obtained with those fiber fabrics which are substantially homogeneous in thickness and which have a high absorption capacity. The second cleaning device 54 cleans the surface 36 of the tape or band 12 in a manner substantially similar to that of the first cleaning device 52. The cleaning fabric 90 administered by an administrator roller 92 is contracted by a shrink roll 94. after passing over a first pulley roller 96 and a second pulley roller 98 in the direction of the arrow 100 to clean the surface 36 of the belt or band 12. The second cleaning device 54 moves in contact with the surface 36 in the direction of the flap 102. A motor 104 under control of the controller 32 moves the contraction roller 94 when necessary to move the fabric 90 in a direction opposite to the movement of the belt or band indicated by the arrow 30. To clean the tape or band 12, a porous absorbent roller 106 is charged with a cleaning liquid 108 held by a bath 110. When necessary, the porous absorbent roller 106 moves in contact with the t ela 90 for the application of the cleaning liquid 108 further. When a sufficient amount of cleaning liquid 108 is applied to the cloth 90, the cloth 90 moves in contact with the surface 36 of the belt or band 12 for cleaning it. When necessary, a fluid supply and pump 112 under control of the controller 36 supplies additional cleaning fluid 108 to the bath 110 to replenish any cleaning fluid that has been used and applied to the fabric 90. As illustrated in FIG. FIG. 3, the cleaning liquid is applied to the fabric material on a cloth surface in an amount sufficient to provide a cleaning amount on the other surface of the fabric opposite the applied surface. While the cleaning fabrics and the tape or band 12 can move in the same direction, they can have the minimum contact length and the highest cleaning efficiency when the fabrics move in substantially opposite directions to the belt or band. By applying cleaning liquid to the absorbent fibers of the fabric for a limited period of time, the belt or band 12 will find a wet section of the fabric saturated with the cleaning liquid for the extraction of any ink or other contaminants. deposited on the tape or band. The cleaning liquid is distributed over both surfaces of the belt or band such that the absorbent cloth absorbs any of the ink residues and contaminants. The tape or band then passes against the cleaner progressively, moreover the wet sections of the fabric until the last point of the application of the cleaning liquid. Finally, the tape or band finds a dry fabric, since the cleaning liquid is applied to the fabric for only a pre-determined period of time so that a dry portion of the fabric remains to remove any remaining liquid. It should be emphasized that because both fabrics are forced into contact with the opposite surfaces of the belt or band, the fleece or fibers of the clean fabrics 60 and 90 can be contacted with each other in the openings 15 of the belt or band. This cooperation between both fabrics tends to extract any of the contaminants and / or inks that have been collected on the interior walls of the artments. As shown in FIG. 3, the mechanism for applying cleaning liquid to the first cloth 60 and the second cloth 90 are different for the first cleaning device 52 and the second cleaning device 54. The present invention, however, is not limited to the mechanism shown and consequently, the pump 76 that includes the nozzle arrays 78 can be used in the second cleaning device 54. Also, the bath 110 containing the cleaning liquid 108 applied by the porous absorbent roller 106 could also be used in the first cleaning device 52, but, for example, in a different configuration as is now shown. To facilitate the complete removal of any ink, contaminant, and cleaning liquid from the belt or band 12, it is preferred to provide a cleaning liquid that is rapidly evaporated. The selection of cleaning fluid, of course, depends on the contaminants and / or the type of ink that is drawn from the tape or band. If the ink is, for example, a water-based ink, then the cleaning liquid can also be water. Accordingly, it is important that the cleaning liquid be miscible with the ink and / or any anticipated contaminant that can be collected on the tape or band 12. Any residual cleaning liquid containing aqueous materials which remain on the tape or band 12 after of the extraction of any residual ink, they can, of course, be extracted by means of absorbent porous materials without wetting, comprising the fabrics 60 and 90. In the recapitulation, a cleaning apparatus for the belt or conveyor belt has been described for the cleaning of the belt or conveyor belt of ink or other contaminants. The cleaning apparatus includes a detector or sensor for the detection of ink and / or contaminants on the first surface and the second surface of the tape or band and a cleaning device for cleaning both surfaces. Although the apparatus has been described for a flatbed inkjet printer, the present invention is applicable to any liquid ink printer having a conveyor belt or strip in which multiple surfaces can be contaminated with ink or other contaminants. In addition, the present invention can be used with any type of belt or conveyor belt. Other solvents than water may be used. It is manifiest. or therefore that a cleaning apparatus for the multiple surfaces of a belt or conveyor belt that fully satisfies the objectives and advantages set forth above has been provided in accordance with the present invention. While this invention has been described in connection with a specific embodiment here, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. For example, instead of passing the fabric through two pulley rollers, a sintered pulley roller can be used. Therefore, it is proposed to adopt all these alternatives, modifications and variations that fall within the spirit and extensive scope of the appended claims.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention. Having described the invention as above, property is claimed as contained in the following

Claims (20)

1. A printing machine of the type in which the liquid ink is deposited on an engraving or printing medium that moves along a path, characterized in that it comprises: a conveyor belt or belt that moves the engraving or printing medium to along the path; a sensor or detector, placed next to the belt or conveyor belt, that detects contaminants on the belt or conveyor belt; and a cleaning apparatus, placed next to the belt or conveyor belt, which cleans the belt or conveyor belt in response to the detector that detects the contaminants on the belt or conveyor belt.

2. The machine for printing according to claim 1, characterized in that it further comprises a controller, in communication with the detector or sensor and the cleaning apparatus, motivating the cleaning apparatus, cleaning the conveyor or belt in response to the detector that detects the pollutants on the band.

3. The printing machine according to claim 2, characterized in that it also comprises a liquid ink printing head adapted to deposit ink on the engraving or printing medium that moves by means of the conveyor belt or belt.

4. The printing machine according to claim 3, characterized in that the cleaning apparatus comprises: a first cleaning device placed next to a first surface of the conveyor belt or b a n d; and a second cleaning device positioned next to a second surface of the belt or conveyor belt.

5. The printing machine according to claim 4, characterized in that the first cleaning device comprises a first flexible fabric that engages or engages with the first surface of the belt or conveyor belt.

6. The printing machine according to claim 5, characterized in that the second cleaning device comprises a second flexible fabric that engages or engages with the second surface of the conveyor belt or belt.

7. The printing machine according to claim 1, characterized in that the sensor or detector comprises a detector or linear sensor that has a sufficient length to detect the contaminants across the width of the belt or conveyor belt.

8. The printing machine according to claim 7, characterized in that the detector comprises an infrared densimeter placed next to a first surface of the belt or conveyor belt.

9. The printing machine according to claim 8, characterized in that the detector comprises a second infrared densimeter placed next to a second surface of the belt or conveyor belt.

10. The printing machine according to claim 7, characterized in that the detector comprises a reflective detector.

11. The printing machine according to claim 1, characterized in that the belt or conveyor belt comprises a light transmitting belt or band.

12. The printing machine according to claim 11, characterized in that the detector comprises a linear arrangement of photodiodes placed next to a first surface of the belt or conveyor belt.

13. The printing machine according to the rei indication 12, characterized in that the detector comprises a linear light source placed next to a second surface of the belt or conveyor belt opposite the linear arrangement of the photodiodes.

14. The printing machine according to claim 1, characterized in that the belt or conveyor belt defines a plurality of openings having inner walls.

15. The printing machine according to claim 14, characterized in that the cleaning apparatus cleans the inner walls of the plurality of openings.

16. The pressing machine according to claim 15, characterized in that the cleaning apparatus comprises a first cleaning device placed next to a first surface of the conveyor belt and a second cleaning device placed next to a second surface of a belt or conveyor belt.

17. The printing machine according to claim 16, characterized in that the first cleaning device comprises a first flexible fabric that engages or engages with a first surface of the belt or conveyor belt.

18. The printing machine according to claim 17, characterized in that a second cleaning device comprises a second flexible fabric that engages or engages with the second surface of the conveyor belt or belt.

19. The printing machine according to claim 18, characterized in that the first flexible fabric includes a fluff having a thickness sufficient to clean the inner walls of the plurality of openings.

20. The printing machine according to claim 19, characterized in that the second flexible fabric includes a fleece of sufficient thickness to allow cleaning of the interior walls of the plurality of openings.