Abstract:
A self-cleaning printer system ( 400 ) with cleaning liquid supply ( 270 ) and print head cleaning assembly ( 32 ) and method of assembling a self-cleaning printer. The printer system ( 400 ) comprises a print head ( 16 ) defining a plurality of ink channels therein, each ink channel terminating in one or more ink ejection nozzles ( 25 ). The print head ( 16 ) also has a surface ( 15 ) thereon surrounding all the nozzles ( 25 ). Contaminant may reside on the surface ( 15 ) and also may completely or partially obstruct one or more of the nozzles ( 25 ). Therefore, the print head cleaning assembly ( 32 ) includes a roller ( 190 ) disposed relative to the surface ( 15 ) and/or nozzles ( 25 ) for cleaning the surface ( 15 ) and/or the nozzles ( 25 ). A cleaning assembly control ( 40 ) directs sliding contact of the roller ( 190 ) with the surface ( 15 ) and/or nozzles ( 25 ). The print head cleaning assembly ( 32 ) is configured to introduce cleaning liquid ( 300 ) to the print head surface ( 15 ) to facilitate and augment cleaning by the roller ( 190 ). In addition, the roller ( 190 ) is combined with channels ( 250, 260 ) for delivery and suction of cleaning liquid ( 300 ).

Description:
FIELD OF THE INVENTION 
     This invention generally relates to a self-cleaning ink jet printer and methods for cleaning the same, and more particularly to a print head cleaning assembly including a roller for use in cleaning the print head surface and ink nozzles for an ink jet printer having a fixed canopy-type gutter. 
     BACKGROUND OF THE INVENTION 
     An ink jet printer produces images by ejecting ink droplets onto a receiver medium in an image-wise fashion. The advantages of non-impact, low-noise, low energy use, and low cost operation in addition to the capability of the printer to print on plain paper mediums are largely responsible for the wide acceptance of ink jet printers in the marketplace. 
     “On demand” ink jet printers utilize a pressurization actuator to produce the ink jet droplet at orifices of a print head. In this regard, either one of two types of actuators may be used including heat actuators and piezoelectric actuators. With heat actuators, a heater placed at a convenient location heats the ink and a quantity of the ink will phase change into a gaseous steam bubble and raise the internal ink pressure sufficiently for an ink droplet to be expelled onto the recording medium. With piezoelectric actuators, a piezoelectric material possessing properties such that an electric field is produced when a mechanical stress is applied. The converse also holds true; that is, an applied electric field will produce a mechanical stress in the material. Some naturally occurring materials possessing these characteristics are quartz and tourmaline. The most commonly produced piezoelectric ceramics are lead zirconate titanate, barium titanate, lead titanate, and lead metaniobate. 
     In the case of “continuous” ink jet printers, electrostatic charging tunnels are placed close to the point where ink droplets are being ejected in the form of a stream. Selected droplets are electrically charged by the charging tunnels. The charged droplets are deflected downstream by the presence of deflector plates that have a predetermined electric potential difference between them. A gutter may be used to intercept the charged droplets, while the uncharged droplets are free to strike the recording medium. 
     Recently a new type of continuous ink jet printer has been disclosed. U.S. Pat. No. 6,079,821 which issued to Chwalek et al. on Jun. 27, 2000, describes a continuous ink jet printer in which on demand asymmetric heating of an ink jet causes selected drops to deflect. In one mode of operation, selected drops are deflected toward an image-recording medium while the other drops are intercepted in a canopy-type gutter that is placed in close proximity (for example, 3 mm) to an ink jet nozzle plate. 
     Inks for high-speed inkjet printers, whether of the “continuous” or “piezoelectric” type, must have a number of special characteristics. For example, the ink should incorporate a nondrying characteristic, so that drying of ink in the ink ejection chamber is hindered or slowed to such a state that by occasional spitting of ink droplets, the cavities and corresponding nozzles are kept open. The addition of glycol facilitates free flow of ink through the ink jet chamber. Of course, the ink jet print head is exposed to the environment where the ink jet printing occurs. Thus, the previously mentioned nozzles are exposed to many kinds of air born particulates. Particulate debris may accumulate on surfaces formed around the nozzles and may accumulate in the nozzles and chambers themselves. That is, the ink may combine with such particulate debris to form an interference that blocks the nozzle or that altars surface wetting to inhibit proper formation of the ink droplet. The particulate debris should be cleaned from the surface and nozzle to restore proper droplet formation. In the prior art, this cleaning is commonly accomplished by brushing, wiping, spraying, vacuum suction, and/or spitting of ink through the nozzle. 
     Thus, ink jet printers can be said to have the following problems: the inks tend to dry-out in and around the nozzles resulting in clogging of the nozzles; and the wiping of the nozzle plate causes wear on plate and wiper, the wiper itself producing particles that clog the nozzle. In addition, cleaning an ink jet nozzle plate that has limited accessibility due to the placement of a fixed gutter poses extra demands on the design of cleaning members and on methods used. 
     Ink jet print head cleaners are known. For example, a print head wiping system for inkjet print heads is disclosed in U.S. Pat. No. 5,614,930, entitled “Orthogonal Rotary Wiping System For Inkjet Printheads” issued Mar. 25, 1997 in the name of William S. Osborne et al. The Osborne et al. patent discloses a rotary service station, which incorporates a wiper-supporting tumbler. The tumbler rotates to wipe the print head along a length of a linearly aligned nozzle. In addition, a wiper scraping system scrapes the wipers to clean the wipers. However, Osborne et al. do not disclose use of an external solvent to assist cleaning and also does not disclose complete removal of the external solvent. In addition, a wiper scraping system is limited by the size constraints imposed by the print head itself. This is particularly true for fixed gutter inkjet print head systems, which partially encloses the print head surfaces. Fixed gutter systems require a mechanism that can work within small tolerances imposed by the integrated gutter in order to clean the print head. The Osborne et al. cannot tolerate the stresses demanded by the tight spacing and limited size of current ink jet print heads. 
     Therefore, there is a need to provide a suitable ink jet printer with a cleaning mechanism, and method of assembling the same, wherein the cleaning mechanism is capable of cleaning the print head surface within the confines of small tolerances and limited spacing. There is also a need to supply cleaning liquid to lubricate and aid cleaning in a manner that does not cause wear of the print head nozzle plate. Furthermore, there is a need for a cleaning mechanism that can operate within the limited spacing imposed by a fixed canopy-type gutter. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a self-cleaning ink jet printer with a cleaning mechanism and method of assembling the same, wherein a surface of a print head belonging to the printer is effectively cleaned. 
     It is another object of the present invention to provide an ink jet print head assembly that includes a cleaning mechanism and method of assembling the same that can be utilized in fixed gutter continuous ink jet printers. 
     With the above objects in view, disclosed is a cleaning mechanism composed of a print head cleaning assembly for use in a self-cleaning printer. The self-cleaning printer includes a print head having a print head surface and an ink channel therein, and a structural member that functions as a gutter for collecting ink disposed opposite to the print head surface. The cleaning mechanism is adapted to clean contaminant from the print head surface. 
     According to an exemplary embodiment of the present invention, a self-cleaning printer is disclosed, wherein the self-cleaning printer includes a print head defining a plurality of ink channels therein, each ink channel terminating in a nozzle. The print head also has a surface thereon surrounding all the nozzles. The print head is capable of letting ink through the nozzles, such that ink jets are subsequently heated to cause ink drops to form and to selectively deviate for printing. Ink drops are intercepted by either a receiver medium, such as paper, or a gutter. In one method of operation, ink is selectively deflected onto a receiver supported by a platen disposed adjacent the print head, while the non-deflected ink drops are intercepted by the gutter. 
     Ink intercepted by the gutter may be recycled. Contaminant such as an oily film-like deposit or particulate matter may reside on the surface and may completely or partially obstruct the nozzle. The oily film may be, for example, grease and the particulate matter may be particles of dirt, dust, metal and/or encrustations of dried ink. Presence of the contaminant interferes with proper ejection of the ink droplets from their respective nozzles and therefore may give rise to undesirable image artifacts, such as banding. It is therefore desirable to clean the contaminant from the surface and the nozzles. 
     Therefore, a cleaning mechanism is disposed relative to the surface and/or the nozzles so as to direct a print head cleaning assembly to clean the contaminant from the surface and/or nozzle via contact with a roller. As described in detail herein, the cleaning mechanism is configured to introduce cleaning liquid to the print head cleaning assembly to facilitate and augment cleaning by the roller. In one embodiment, the roller comprises a rotating shaft surrounded by a covering made of a sponge-like porous material. A driver connected and/or integrated with the rotating shaft provides the movement of the roller. The driver is driven by a motor. 
     In a preferred embodiment, cleaning liquid is supplied to the print head surface through channels provided in the gutter. The sponge-like material assists the contaminants in adhering to the roller during the back and forth movement of the roller across the print head surface. 
     A feature of the present invention is the provision of a mechanism to align and transport the roller during cleaning operation. 
     Another feature of the present invention is the provision of an ultrasonic transducer to energize the cleaning action by the roller and the cleaning liquid. 
     A technical advantage of the present invention is that the cleaning mechanism belonging to the invention cleans the contaminant from the surface and/or nozzle(s) in the confined space between the print head surface and the fixed gutter. 
     These and other objects, features and advantages of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description taken in conjunction with the appended drawings, which show and describe illustrative embodiments of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter of the present invention, it is believed the invention will be better understood from the following detailed description taken in conjunction with the accompanying drawings wherein: 
     FIG. 1A shows a simplified block schematic diagram of a first embodiment printer equipped with a page width print head with fixed gutter and cleaning mechanism disposed adjacent to the print head; 
     FIG. 1B shows a simplified block schematic diagram of a second embodiment printer the printer equipped with a scanning print head with fixed gutter and cleaning mechanism disposed adjacent to the print head; 
     FIG. 2 is an isotopic view of the print head with fixed gutter, the print head defining a plurality of channels therein, each channel terminating in a nozzle; 
     FIG. 3 is a side view of a print head according to the invention, showing deflected ink drops directed toward a receiving medium and non-deflected ink drops intercepted by the fixed gutter; 
     FIG. 4 is a fragmented view in cross-section of the print head shown in FIG. 3; 
     FIG. 5 is a fragmented view in cross-section of a contaminated print head with schematic representation of misaligned ink drops due to contaminant; 
     FIG. 6 is a sectional view of a roller-cleaning assembly having a canopy, a roller and rotating shaft for removing contaminant from a print head surface, in accordance with a preferred embodiment of the present invention; 
     FIG. 7 shows a simplified block schematic diagram of an exemplary third embodiment printer equipped with a page width print head with fixed gutter and lengthwise roller cleaning assembly disposed adjacent to the print head; 
     FIG. 8 shows a simplified block schematic diagram of an exemplary fourth embodiment printer equipped with a page width print head with fixed gutter and widthwise roller cleaning mechanism disposed on the same block as print head; 
     FIG. 9 shows an isometric view of print head with a roller-cleaning assembly aligned for widthwise translation; 
     FIG. 10 shows a side view of the roller-cleaning assembly of FIG. 9 aligned for widthwise translation; 
     FIG. 11 an isometric view of print head with roller-cleaning assembly aligned for lengthwise translation, according to a fourth exemplary embodiment; 
     FIG. 12 shows a side view of the roller-cleaning assembly of FIG. 11; 
     FIG. 13 is a sectional view of modified gutter delivering cleaning liquid to print head surface; 
     FIG. 14 shows a simplified block schematic diagram of an exemplary fifth embodiment printer equipped with a page width print head with fixed gutter and swing-arm roller mechanism disposed on the same block as the print; 
     FIG. 15 shows an isometric view of a swing-arm roller-cleaning assembly positioned at rest and during cleaning. 
     FIG. 16 shows a sectional view of an example of a swing-arm roller cleaner; 
     FIG. 17 shows a sectional view of an example of a swing-arm roller cleaner with air channel supply in modified gutter; 
     FIG. 18 shows another example of a swing-arm roller with canopy in cleaning position and in rest position. 
     FIG. 19 shows swing-arm roller of FIG. 18 during printing operation; and 
     FIG. 20 shows a simplified block schematic diagram of an exemplary sixth embodiment printer equipped with a page width print head with fixed gutter and cleaning mechanism disposed on same block as print head using an ultrasonic transducer coupled to the roller-cleaning assembly; 
    
    
     Numerals and parts in the detailed description correspond to like references in the figures unless otherwise indicated. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The present description will be directed in particular to elements forming part of, or cooperating more directly with, apparatus in accordance with the present invention. It is to be understood that elements not specifically shown or described may take various forms well known to those skilled in the art. 
     Therefore, referring to FIGS. 1A,  1 B,  2  and  3  therein are shown first and second embodiments denoted generally as  410  and  420 , respectively, for self-cleaning printer systems which include an image source  10 , such as a scanner or a computer that provides raster image data, outline image data in the form of a page description language, or other forms of digital image data. The image source  10  is converted to half-toned bitmap image data by an image-processing unit  12 , which stores the image data in memory. A plurality of heater control circuits  14  read the data from memory within the image-processing unit  12  and apply time-varying electrical pulses to a set of nozzle heaters  50  that are part of a print head  16 . 
     The action of the nozzle heaters  50  and print head  16  during printing is shown in FIG. 3 wherein the electrical pulses are applied at an appropriate time, and to the appropriate nozzle, so that drops  23  form a continuous ink jet stream to create spots on a recording medium  18 , typically paper, in an appropriate position designated by the data in the memory of the image processing unit  12 . Non-deflected ink drops  21  formed in the non-printing area are intercepted by the gutter  17 , which, as shown, is fixed in relation to the print head  16 . Print head  16  may be a page width print head or a scanning type print head. 
     Referring to FIG.  1 A and FIG. 1B, recording medium  18  is moved relative to the print head  16  by a recording medium transport system  20 , which is electronically controlled by a paper transport control system  22 , and which, in turn, is controlled by a micro-controller  24 . The paper medium transport control system  22  shown in FIG.  1 A and FIG. 1B is shown in schematic form only, and many different mechanical configurations are possible, as is known to those of skill in the art. For example, a transfer roller could be used as a paper medium transport system  22  to facilitate transfer of the ink drops  23  to recording medium  18 . Such transfer roller technology is well known in the art. In the case of page width print heads, it is most convenient to move the recording medium  18  past a stationary print head. However, in the case of a scanning print system (as shown schematically in FIG.  1 B), it is usually most convenient to move the print head along one axis (the sub-scanning direction) and the recording medium  18  along an orthogonal axis (the main scanning direction) in a relative raster motion. 
     Referring to FIGS. 1A,  1 B,  3  and  4 , ink is contained in an ink reservoir  28  under pressure. In the non printing state, continuous ink jet drop streams are unable to reach the recording medium  18  due to the position of gutter  17  that blocks the stream of ink to allow a portion of the ink to be recycled by an ink recycling unit  19 . The ink-recycling unit  19  reconditions the ink and feeds it back to ink reservoir  28 . Such ink recycling units are well known in the art. The ink pressure suitable for optimal operation will depend on a number of factors, including geometry and thermal properties of the nozzles and thermal properties of the ink. A constant ink pressure can be achieved by applying pressure to ink reservoir  28  under the control of ink pressure regulator  26 . 
     Ink  29  is distributed to the back surface of the print head  16  by an ink channel device  30  and through ink channel  31 , as shown in FIG.  4 . The ink preferably flows through slots and/or holes etched through silicon substrate of print head  16  to its front surface  15 , where a plurality of nozzles  25  and heaters  50  are situated. FIG. 2 is an isotropic view of the print head  16  and gutter  17 . With print head  16  fabricated from silicon, it is possible to integrate heater control circuits  14  with the print head  16 . Gutter  17  intercepts non-deflected ink drops  21 , while deflected ink drops  23  land on the recording medium  18 . Deflection may be caused by a variety of methods including the asymmetric heating method discussed in U.S. Pat. No. 6,079,821. 
     Turning now to FIG. 5, it has been observed that the front surface  15  may become fouled by contaminant  55 . Contaminant  55  may be, for example, an oily film or particulate matter residing on the front surface  15 . Contaminant  55  also may partially or completely obstructs one or more of the plurality of nozzles  25 . The particulate matter may be, for example, particles of dirt, dust, metal and/or encrustations of dried ink. The oily film may be, for example, grease or the like. Presence of contaminant  55  is undesirable because when contaminant  55  completely obstruct one or more of the plurality of nozzles  25 , ink is prevented from being ejected from one or more of the nozzles  25 . It should be understood that the terms “nozzle” and “nozzles” are used interchangeably throughout either in the singular or plural as may be appropriate. 
     In addition, when contaminant  55  partially obstructs nozzle  25 , flight of ink droplets  60  may be diverted from first axis  63  to travel along a second axis  65  (as shown). If ink droplets  60  travels along second axis  65 , ink droplets  60  will land on recording medium  18  in an unintended location. In this manner, such complete or partial obstruction of nozzle  25  leads to printing artifacts such as “banding”, a highly undesirable result. A similar printing artifact results if non-selected drops  21  travel on third axis  66 . Also, the presence of contaminant  55  may alter surface wetting and inhibit proper formation of a droplets  60 . Therefore, it is desirable to clean and/or contaminant  55  to avoid these and other printing artifacts. 
     Therefore, the self-cleaning printer systems  410  and  420  are equipped with a cleaning mechanism  140  that can be used for simultaneously removing contaminant  55  from front surface  15  of the print head  16  and the nozzles  25 , according to the invention. In particular, the self-cleaning printer system  410  of FIG. 1A refers to a page width print head, while self-cleaning printer system  420  of FIG. 1B refers to a scanning type print head. The cleaning mechanism  140  includes a print head cleaning assembly  32 , disposed for directing flow of cleaning liquid  300  using a roller  190  that moves along the front surface  15  and across nozzles  25  to clean contaminant  55  therefrom. The cleaning liquid  300  mentioned hereinabove may be any suitable liquid solvent composition, such as water, ink, isopropanol, diethylene glycol, diethylene glycol monobutyl ether, octane, acids and bases, surfactant solutions and any combination thereof. Complex liquid compositions may also be used, such as microemulsions, micellar surfactant solutions, vesicles and solid particles dispersed in the cleaning liquid  300 . 
     To better understand the implementation of a print head cleaning assembly  32  and, in particular, the roller  190 , reference is made to FIG.  6 . The roller  190  is preferably coated or covered with a soft porous sponge-like material that is not abrasive to print head surface  15  and is capable of holding cleaning liquid  300  and contaminant  55 . Suitable materials for the soft porous sponge-like material include polyurethane sponge or foam, expanded polytetrafluoroethylene and other similar substances. Accordingly, the roller  190  will be understood to mean a roller with a roller covering or coating consisting of a soft porous sponge-like material with such properties. 
     Arrows  604   a  and  604   b  indicate the motion of roller  190  when driven by a driver (not shown) integrated with and connected to rotating shaft  191 , Such a driver can, in turn, be driven by a motor (also not shown). Canopy  80  is constructed with internal channels  250 ,  260  to supply filtered or unused cleaning liquid to the print head surface  15  and to provide suction to remove used cleaning solution. In particular, cleaning liquid  300  may be delivered through channel  250  and suction applied through channel  260  by connection to circulation pump  36  as shown in FIG.  1 A and FIG.  1 B. Adjacent to vacuum slot  262  is a wiper blade  198  that squeezes used cleaning liquid from roller  190 . As a result of this arrangement, a flow of cleaning liquid  300  is set up on the roller  190  affording cleaning of contaminant from the print head surface  15  as well as nozzles  25 . The flow of the cleaning liquid  300  may be reversed if needed by switching the channels  250  and  260  and/or by reversing the direction of rotation of roller  190 . 
     In operation, upon receiving an electronic signal from micro-controller  24  via cleaning assembly control  40 , roller  190  and cleaning liquid pump  36  are activated causing roller  190  to rotate at a predetermined rate and cleaning liquid  300  to be sprayed onto the roller  190 . Micro-controller  24  also sends an electronic signal to print head transport control  42  which commands print head  16  to translate toward the roller  190  following arrow  44   a.  Preferably, the roller  190  is pre-aligned with surface  15  of print head  16  so that when print head  16  reaches roller  190 , the print head surface  15  and nozzles  25  are in contact with the roller  190 . 
     As print head  16  continues to travel along direction of arrow  44   a,  contaminant  55  on print head surface  15  and in nozzle  25  is removed by the roller  190 , which is rotating and thereby cleaning the print head surface  15  and nozzles  25 . Contaminated cleaning liquid on roller  190  is then squeezed from the roller  190  by blade  198  and removed by vacuum slots  262 . The process of spraying cleaning solution on to roller  190  and then removing it once it has been used ensures efficient cleaning of print head surface  15  and nozzles  25 . After print head surface  16  and nozzles  25  have been cleaned, print head  16  is translated back along direction of arrow  44   b  to its normal printing position. Note, that in printer systems  410  and  420 , the roller  190  is preferably cantilevered. If roller  190  were supported by struts at both ends, it is possible that strut closest to gutter would collide with gutter  17  during cleaning. 
     As can be appreciated by those of ordinary skill, the process of engaging roller  190  with print head surface  15  described above is one of many methods of using the cleaning mechanism  190  to clean the print head surface  15  and nozzles  25 . For example, rather than having print head surface  15  pre-aligned with the print head cleaning assembly  32 , the print head cleaning assembly  32  may be optionally equipped with its own translation capability. By way of example only, print head cleaning assembly  32  may be supported on an elevator and lifted in direction of arrow  46   b  to the appropriate location in order to engage the roller  190  with print head surface  15 . After print head surface  15  and nozzles  25  have been cleaned, the print head  16  is translated back along direction of arrow  44   b  to its normal printing position, and print head cleaning assembly  32  is lowered to its rest position along direction of arrow  46   a.    
     Note that in the arrangement shown in FIGS. 1A and 1B, the roller  190  crosses one of the nozzles  25  at a time, possibly pushing contaminant  55  toward another nozzle. In order to avoid pushing contaminant  55  toward other nozzles, it is advantageous to translate the print head cleaning assembly  32  in the direction of fifth arrow  70   a  as shown in FIG.  7 . Therefore, according to a third embodiment of the present invention, a self-cleaning ink jet printer system  430  is disclosed and equipped with a print head cleaning assembly  32  having a page width length roller  190  and canopy  80  that is translated in direction of fifth arrow  70   a.  Roller  190  is translated in direction  70   a  and  70   b  along a guide rail (not shown). The axis of rotation for roller  190  is parallel to the linear array of nozzles  25 . As shown, roller  190  has a page width length making it suitable for use with page width ink jet print heads or a scanning type print heads. 
     Referring to FIGS. 8,  9  and  10 , therein is shown an example of a fourth embodiment self cleaning ink jet printer system, denoted generally as  440 , in which a print head cleaning assembly  32  is fixed to the same block as the print head  16 . In order to clean the print head surface  15 , roller  190  translates along guide rail  77 . As previously discussed, roller  190  is covered with roller covering and is provided with canopy  80 . Canopy  80  provides means for the delivery of cleaning liquid  300  and removal of used cleaning liquid  305 . A wiping pad  90  (shown in FIG. 9) is provided as an option for enhanced cleaning of the roller  190 . In this way, the roller  190  can be scrubbed by the wiping pad  90  when travelling in direction of arrows  75   a  and  75   b.  In FIGS. 8,  9 , and  10 , the roller  190  is oriented orthogonal to the nozzles  25 . 
     Referring to FIGS. 11 and 12, there is shown the self cleaning ink jet printer system  440  in which print head cleaning assembly  32  is provided on the same block of print head  16  with the roller  190  being at page width length. In particular, roller  190  is oriented along the axis of rotation parallel to nozzles  25  and incorporated on same block as print head  16 . In order to clean the print head surface  15 , roller  190  translates along guide rail  115  extending from the frame  110 . As previously discussed, the roller  190  is covered with a soft porous material and is provided with canopy  80  that facilitates cleaning of the roller  190 . In FIG. 11, the roller  190  and canopy  80  are represented as  630  for purpose of clarity of illustration. A wiping pad  90  is provided as an option for enhanced cleaning of the roller  190  then permits scrubbing by the wiping pad  90  when the  190  roller travels in direction of arrows  79   a  and  79   b.    
     FIG. 13 illustrates how cleaning liquid  300  can be supplied to the print head surface  15  through cleaning liquid supply channel  85  in modified gutter  17   a.  In this case, when roller  190  translates in direction of arrow  79   a,  cleaning of print head surface  15  and nozzles  25  will be enhanced due to cleaning solution  300  sprayed from modified gutter  17   a  onto the roller  190 . Similarly, if the cleaning solution  300  is ink, ink may be allowed to flow out of nozzle  25  onto print head surface  15  to provide cleaning solution  300  to the roller  190 . In either case, excess cleaning liquid  300  on surface of roller  190  may be removed through vacuum slot  262  and by wiper blade  198  in canopy  80 . 
     Referring to FIGS. 14 and 15, therein is shown a fifth embodiment self-cleaning ink jet printer system  450  of the present invention in which the roller  190  contacts print head surface  15  by a swing-arm mechanism  455  during cleaning. In this regard, upon receiving electronic information from micro-controller  24  via cleaning assembly control  40 , a motor  500  works with a swing-arm  502  to swing the roller  190  in direction of arrow  605  into cleaning position on print head  15 . 
     There are many arrangements for configuring the motor  500  and swing arm  502  as can be appreciated by those of ordinary skill. For example, as shown in FIG. 16, the print head body  16  may be modified to provide a recess to house roller  190  in either the resting or cleaning position. During roller cleaning, the roller  190  is activated to scrape against wiper blade  610 , causing used cleaning liquid  305  to be squeezed out of roller and drain into channel  615 . Since ink itself can be used as a cleaner, cleaning liquid  300  may be supplied through nozzles  25  if the cleaning liquid is ink, or through modified gutter  17   a.  Optionally, as shown in FIG. 17, the modified gutter  17   a  may also be provided with air channel  87  to direct air or gas to surface  15  following the direction of arrow  100  after cleaning operation. In another example of a fifth embodiment self-cleaning ink jet printer system  450 , the swing-arm roller mechanism  455  may be provided with a canopy  80  as shown in FIG.  18 . FIG. 18 shows swing arm roller mechanism  455  in both the cleaning position and in rest position (shown in phantom). FIG. 19 shows, roller  190  in rest position during printing in non-deflected ink drops  21  are captured by gutter  17  and deflected drops  23  proceed to mark a recording medium (not shown). 
     Referring to FIG. 20 therein is shown an example of a sixth embodiment of the ink jet printer system  460  capable of simultaneously removing contaminant  55  from print head surface  15  and nozzles  25 . Sixth embodiment ink jet printer  460  is substantially similar to first, second, third, fourth and fifth embodiment ink jet printer systems  410 ,  420 ,  430 ,  440  and  450 , respectively, except that the roller  190  is vibrated by an ultrasonic transducer  470 . Electrical signals and power from cleaning assembly control  40  is delivered ultrasonic transducer  470  through electrical conduit  480 . Obviously, the transducer  470  may be coupled with the roller  190  in a variety of ways, although only one example is shown in FIG.  20 . Furthermore, ultrasonic transducer  470  may be coupled to cleaning liquid supply  270  to energize the cleaning liquid  300  for enhanced cleaning of print head surface  15  and nozzles  25 . 
     Therefore, what is provided and disclosed are variations and embodiments of self-cleaning printer system  410 ,  420 ,  430 ,  440 ,  450  and  460  with a corresponding cleaning mechanism  140  including variations of a print head cleaning assembly  32  with one or more versions of a roller  190  providing a mechanism and method of assembling corresponding self-cleaning printers with a cleaning mechanism  140  capable of cleaning the print head surface  15  and nozzles  25  of the printer. 
     While the invention has been described with particular reference to its preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements of the preferred embodiments without departing from the invention. In addition, many modifications may be made to adapt a particular situation and material to a teaching of the present invention without departing from the essential teachings of the invention. 
     PARTS LIST 
       10  . . . image source 
       12  . . . image processing unit 
       14  . . . heater control circuits 
       15  . . . front surface 
       16  . . . print head 
       17  . . . gutter 
       17   a  . . . modified gutter 
       18  . . . recording medium 
       19  . . . ink recycling unit 
       20  . . . recording medium transport system 
       21  . . . non-deflected ink drop 
       22  . . . recording medium transport control system 
       23  . . . deflected ink drop 
       24  . . . micro-controller 
       25  . . . nozzle 
       26  . . . ink pressure regulator 
       28  . . . ink reservoir 
       29  . . . ink 
       30  . . . ink channel device 
       31  . . . ink channel 
       32  . . . print head cleaning assembly 
       36  . . . circulation pump 
       38  . . . piping 
       40  . . . cleaning assembly control 
       42  . . . print head transport control 
       44   a  . . . first arrow 
       44   b  . . . second arrow 
       46   a  . . . third arrow 
       46   b  . . . fourth arrow 
       50  . . . nozzle heaters 
       55  . . . contaminant 
       60  . . . ink droplet 
       63  . . . first axis 
       65  . . . second axis 
       66  . . . third axis 
       70   a  . . . fifth arrow 
       70   b  . . . sixth arrow 
       75   a  . . . seventh arrow 
       75   b  . . . eighth arrow 
       77  . . . guide rail 
       79   a  . . . ninth arrow 
       79   b  . . . tenth arrow 
       80  . . . canopy 
       85  . . . cleaning liquid supply channel in modified gutter 
       87  . . . air channel in modified gutter  17   a    
       90  . . . wiping pad 
       100  . . . arrow for air flow in  450   
       110  . . . frame 
       115  . . . guide rail 
       140  . . . cleaning mechanism 
       190  . . . roller 
       191  . . . rotating shaft 
       198  . . . blade 
       250  . . . cleaning liquid channel in canopy 
       260  . . . suction channel in canopy 
       262  . . . vacuum slot in canopy  80   
       270  . . . cleaning liquid reservoir 
       280  . . . filter 
       300  . . . cleaning liquid 
       305  . . . used cleaning liquid 
       410  . . . first embodiment printer system 
       420  . . . second embodiment printer system 
       430  . . . third embodiment printer system 
       440  . . . fourth embodiment printer system 
       450  . . . fifth embodiment printer system 
       455  . . . swing arm mechanism 
       460  . . . sixth embodiment printer system with ultrasonic transducer 
       470  . . . ultrasonic transducer 
       480  . . . electrical conduit 
       500  . . . motor to drive swing-arm roller 
       502  . . . swing arm 
       604   a  . . . arrow 
       604   b  . . . arrow 
       605  . . . arrow 
       610  . . . wiper blade in fifth embodiment self-cleaning printer 
       615  . . . channel 
       630  . . . cobination of roller  190 , roller covering  195  and canopy  80