Abstract:
An elongate hand-held printer device for printing on a medium when a user moves said device over the medium. The device includes an upper and a lower moulding configured to complementarily receive each other to define a housing, said housing defining an ink ejection slot along, and a printhead module housed in the housing. The module has a plurality of micro-electromechanical ejection devices for operatively ejecting ink via the ink ejection slot. The device also includes an ink supply cartridge housed in the housing, the cartridge for supplying the printhead module with ink, as well as an optical encoder wheel to facilitate regulation of a printing rate of the printhead module as the device is moved along the medium.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application is a Continuation of U.S. Ser. No. 10/503,900 filed on Aug. 9, 2004, now issued U.S. Pat. No. 7,426,050, which is a 371 of PCT/AU03/00150, filed Feb. 12, 2003, all of which are herein incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The following invention relates to improvements in printer and copier technology, more particularly to drop-on-demand printers and even more particularly to a combined printer-scanner having a print-width drop-on-demand fixed printhead system which can be swiped across a surface by a user to effect both scanning and printing operations. 
     BACKGROUND 
     Known prior art printers typically incorporate a supply of print media and employ a print media feed mechanism to transport the print media past the printhead(s) to effect printing onto the print media. It is essential during a printing operation to synchronise the speed of the print media with the printing rate of the printhead(s) to ensure a faithful reproduction of the image being printed. Heretofore, the synchronisation of the print media with the printhead(s) has been relatively simple to accomplish because the print media feed mechanism, including the supply of print media, forms an integral part of the printer or copier. The speed of the print media is therefore known and fixed, as is the speed at which the printhead(s) and print controller operate, with synchronisation between these features being accomplished using simple mechanical features such as gears, stepper motors and the like. 
     Such features however, in particular the need to have a supply of print media accommodated within the printers, have made these printers larger and heavier than they otherwise need be. Even in more compact printers and copiers employing a monolithic page-width drop-on-demand printhead arrangement, where the printhead is fixed, there is still a need to have a supply of print media and a print media drive mechanism integral to the printer to ensure proper synchronisation between ink ejection and print media transport. These requirements thus limit the minimum printer size possible. 
     Conventional photocopiers are a bulky, non-portable component. Modern personal computers can perform the basic functions of a bulky photocopier if a computer has a scanner and a printer communicating therewith. Photocopiers suffer the same problems noted above. That is, they must store a supply of print media and provide the necessary media transfer componentry to guide the media past the printing mechanism as copying occurs. 
     CO-PENDING APPLICATIONS 
     Various methods, systems and apparatus relating to the present invention are disclosed in the following co-pending applications filed by the applicant or assignee of the present invention simultaneously with the present application: 
     
       
         
               
               
               
               
               
             
           
               
                   
               
             
             
               
                 PCT/AU03/00154 
                 PCT/AU03/00151 
                 PCT/AU03/00150 
                 PCT/AU03/00145 
                 PCT/AU03/00153 
               
               
                 PCT/AU03/00152 
                 PCT/AU03/00168 
                 PCT/AU03/00169 
                 PCT/AU03/00170 
                 PCT/AU03/00162 
               
               
                 PCT/AU03/00146 
                 PCT/AU03/00159 
                 PCT/AU03/00171 
                 PCT/AU03/00149 
                 PCT/AU03/00167 
               
               
                 PCT/AU03/00158 
                 PCT/AU03/00147 
                 PCT/AU03/00166 
                 PCT/AU03/00164 
                 PCT/AU03/00163 
               
               
                 PCT/AU03/00165 
                 PCT/AU03/00160 
                 PCT/AU03/00157 
                 PCT/AU03/00148 
                 PCT/AU03/00156 
               
               
                 PCT/AU03/00155 
               
               
                   
               
             
          
         
       
     
     The disclosures of these co-pending applications are incorporated herein by cross-reference. 
     RELATED PATENT APPLICATIONS AND PATENTS 
     
       
         
               
               
               
               
               
             
           
               
                   
               
             
             
               
                 6,566,858 
                 6,331,946 
                 6,246,970 
                 6,442,525 
                 PCT/AU01/00141 
               
               
                 09/505,951 
                 PCT/AU01/00139 
                 6,816,968 
                 6,757,832 
                 PCT/AU01/00140 
               
               
                 PCT/AU00/00741 
                 6,238,044 
                 PCT/AU00/00742 
                 6,425,661 
                 6,227,652 
               
               
                 6,213,588 
                 6,213,589 
                 6,231,163 
                 6,247,795 
                 6,394,581 
               
               
                 6,244,691 
                 6,257,704 
                 6,416,168 
                 6,220,694 
                 6,257,705 
               
               
                 6,247,794 
                 6,234,610 
                 6,247,793 
                 6,264,306 
                 6,241,342 
               
               
                 6,247,792 
                 6,264,307 
                 6,254,220 
                 6,234,611 
                 6,302,528 
               
               
                 6,283,582 
                 6,239,821 
                 6,338,547 
                 6,247,796 
                 6,557,977 
               
               
                 6,390,603 
                 6,362,843 
                 6,293,653 
                 6,312,107 
                 6,227,653 
               
               
                 6,234,609 
                 6,238,040 
                 6,188,415 
                 6,227,654 
                 6,209,989 
               
               
                 6,247,791 
                 6,336,710 
                 6,217,153 
                 6,416,167 
                 6,243,113 
               
               
                 6,283,581 
                 6,247,790 
                 6,260,953 
                 6,267,469 
                 6,273,544 
               
               
                 6,309,048 
                 6,420,196 
                 6,443,558 
                 6,439,689 
                 6,378,989 
               
               
                 6,848,181 
                 6,634,735 
                 PCT/AU98/00550 
                 PCT/AU00/00095 
                 6,390,605 
               
               
                 6,322,195 
                 6,612,110 
                 6,480,089 
                 6,460,778 
                 6,305,788 
               
               
                 PCT/AU00/00172 
                 6,426,014 
                 PCT/AU00/00338 
                 6,364,453 
                 PCT/AU00/00339 
               
               
                 6,457,795 
                 PCT/AU00/00581 
                 6,315,399 
                 PCT/AU00/00580 
                 6,338,548 
               
               
                 PCT/AU00/00582 
                 6,540,319 
                 PCT/AU00/00587 
                 6,328,431 
                 PCT/AU00/00588 
               
               
                 6,328,425 
                 PCT/AU00/00589 
                 6,991,320 
                 PCT/AU00/00341 
                 6,595,624 
               
               
                 PCT/AU00/00340 
                 PCT/AU00/00749 
                 6,417,757 
                 PCT/AU01/01332 
                 7,095,309 
               
               
                 PCT/AU01/01318 
                 6,854,825 
                 PCT/AU00/00750 
                 7,075,677 
                 PCT/AU00/00751 
               
               
                 6,428,139 
                 PCT/AU00/00752 
                 6,575,549 
                 PCT/AU01/00502 
                 PCT/AU00/00583 
               
               
                 6,383,833 
                 PCT/AU02/01120 
                 PCT/AU00/00593 
                 6,464,332 
                 PCT/AU00/00333 
               
               
                 PCT/AU00/01513 
                 6,428,142 
                 PCT/AU00/00590 
                 6,390,591 
                 PCT/AU00/00591 
               
               
                 7,018,016 
                 PCT/AU00/00592 
                 6,328,417 
                 PCT/AU00/00584 
                 6,322,194 
               
               
                 PCT/AU00/00585 
                 6,382,779 
                 PCT/AU00/00586 
                 6,629,745 
                 PCT/AU00/01514 
               
               
                 6,565,193 
                 PCT/AU00/01515 
                 6,609,786 
                 PCT/AU00/01516 
                 6,609,787 
               
               
                 PCT/AU00/01517 
                 6,439,908 
                 PCT/AU00/01512 
                 6,684,503 
                 PCT/AU00/00753 
               
               
                 6,755,513 
                 PCT/AU00/00594 
                 6,409,323 
                 PCT/AU00/00595 
                 6,281,912 
               
               
                 PCT/AU00/00596 
                 6,604,810 
                 PCT/AU00/00597 
                 6,318,920 
                 PCT/AU00/00598 
               
               
                 6,488,422 
                 PCT/AU01/01321 
                 6,655,786 
                 PCT/AU01/01322 
                 6,457,810 
               
               
                 PCT/AU01/01323 
                 6,485,135 
                 PCT/AU00/00516 
                 6,795,215 
                 PCT/AU00/00517 
               
               
                 7,154,638 
                 PCT/AU00/00511 
                 6,859,289 
                 PCT/AU00/00754 
                 6,977,751 
               
               
                 PCT/AU00/00755 
                 6,398,332 
                 PCT/AU00/00756 
                 6,394,573 
                 PCT/AU00/00757 
               
               
                 6,622,923 
               
               
                   
               
             
          
         
       
     
     SUMMARY OF THE INVENTION 
     According to a first aspect of the present invention there is disclosed a combined printer-scanner adapted to be movable by a user relative to a surface and being operable in a scanning mode and a printing mode, the printer-scanner comprising: 
     a speed sensor adapted to measure the speed at which the printer-scanner is moved relative to the surface by the user; 
     a scanning device synchronised with the speed sensor and being adapted, when the printer-scanner is in scanning mode, to capture image data representative of an image disposed on the surface as the printer-scanner is moved relative to the surface by the user; 
     a memory adapted to store the image data; 
     a printhead arrangement synchronised with the speed sensor and being adapted, when the printer-scanner is in printing mode, to effect printing of the image data onto a print media as the printer-scanner is moved relative to the print media by the user; and 
     a housing adapted to house the speed sensor, the scanning device, the memory and the printhead arrangement. 
     Preferably, the printhead arrangement comprises a plurality of ink ejection nozzles. 
     Preferably, the printer-scanner further comprises a print controller adapted to:
         (a) convert the image data stored in the memory into a plurality of drop ejection control signals;   (b) receive speed data from the speed sensor, the speed data being indicative of the speed at which the printer-scanner is moved relative to the print media by the user; and   (c) operate the ink ejection nozzles in the printhead arrangement in accordance with the drop ejection control signals at a rate determined using the speed data, to thereby effect printing of the image data onto the print media.       

     Preferably, the speed sensor comprises an optical encoder wheel adapted to operate in contact with the surface and to rotate as the printer-scanner traverses the surface. More preferably, the optical encoder wheel comprises: 
     a series of circumferentially spaced markings; and 
     an optical sensor for detecting the markings as the markings pass the optical sensor during rotation of the optical encoder wheel. 
     Preferably, the printer-scanner further comprises a power supply housed within the housing, the power supply comprising a cartridge in which there is disposed a battery and an ink supply, the cartridge being removable from the housing to allow removal and replacement of the battery and the ink supply substantially simultaneously. 
     Preferably, the printer-scanner further comprises: 
     a capping arrangement moveable between a capped position in which the capping arrangement substantially obstructs the ejection of ink from the ink ejection nozzles and an un-capped position in which the capping arrangement does not substantially obstruct the ejection of ink from the ink ejection nozzles; and 
     a capping actuator disposed on the printer-scanner so as to be operable by a user as the user moves the printhead arrangement relative to the print media. 
     Preferably, the printer-scanner further comprises a biasing member adapted to bias the capping arrangement towards the capped position. 
     Preferably, the capping arrangement comprises a mounting portion pivotally mounted on the printer and a capping arm extending substantially perpendicularly from the mounting portion to a distal end, the distal end lying adjacent the ink ejection nozzles to substantially obstruct ink ejection from the ink ejection nozzles when the capping arrangement is mounted on the printer-scanner and is in the capped position. 
     Preferably, the printer-scanner further comprises a finger pad formed on the mounting portion of the capping arrangement. 
     Preferably, the memory is further adapted to store printable information and the printhead arrangement is adapted to effect printing of the printable information onto the print media as the printer-scanner is moved relative to the print media by the user. 
     Preferably, the printable information is received from a source external to the printer-scanner via a communications receiver. More preferably, the communications receiver is an infra-red receiver, the printer-scanner further comprising an infra-red window through which infra-red signals may pass to the infra-red receiver. 
     Preferably, the printer-scanner further comprises an ink supply adapted to store ink and to supply the ink to the printhead arrangement. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A preferred form of the present invention will now be described by way of example only with reference to the accompanying drawings wherein: 
         FIG. 1  is a perspective view of a printer-scanner shown in use to scan an image from a page; 
         FIG. 2  is a perspective view of the printer-scanner of  FIG. 1  in use in a printing operation; 
         FIG. 3  is an exploded view of the printer-scanner of  FIGS. 1 and 2 ; 
         FIG. 4  is a perspective end view of the printer-scanner; and 
         FIG. 5  is an inverted perspective view of the printer-scanner. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the figures, a preferred embodiment of the printer-scanner of the present invention is shown generally at  10  in  FIG. 1 . In this figure, the printer-scanner  10 , under guidance of a user, traverses a page  20  in the direction of the arrow  21  to scan an image  22  from the page  20 . 
     As shown in  FIG. 2 , the printer-scanner  10  also can be guided by a user to traverse a page  20 A in the direction of arrow  21  to print an image  22 A on the page  20 A. This printed image can be a reproduction of image  22  or could be any other image depending upon the way in which the printer-scanner is used. 
     An exploded view of the printer-scanner  10  is shown in  FIG. 3 . The printer-scanner  10  includes a lower moulding  11 , an upper moulding  12  and a removable end cap  13  each of which may be formed of any suitable plastics, metal or similar material. 
     The upper and lower mouldings each include media slides  14  formed at each end of the mouldings on the bottom surface thereof. The slides  14  protrude from the bottom surface of the mouldings and serve to elevate the printer-scanner as the printer-scanner traverses the print media. This results in minimal friction between the printhead and print media and prevents contact between the printer-scanner and freshly printed ink which could otherwise disturb the printed image. 
     When joined, the upper and lower mouldings reveal an ink ejection slot  15  ( FIG. 5 ) through which ink is ejected during printing. A capping device  50 , preferably of metal is received in a recess  17  formed in the upper moulding  12 . The capping device  50 , pivots about a pivot point from a capped position in which a capping arm  52  of the capping device  50  blocks the ink ejection slot  15  to an uncapped position wherein ink ejection is unrestricted. Operation of the capping device  50  occurs using a finger pad  55  formed integrally with the capper. 
     Internally, the printer-scanner  10  includes a printhead module  30  in which is disposed a plurality of ink distribution channels leading to an array of ink ejection nozzles  31  which are aligned with the ink ejection slot  15  formed between the upper and lower mouldings  12 ,  11 . An ink supply cartridge  32  stores inks, preferably in four colors namely cyan, magenta, yellow and black, to provide for full color printing. Alternatively, or in addition, infra-red ink may be provided. The ink cartridge  32  supplies ink to the ink distribution channels of the printhead module  30  through an ink connector  33 . 
     Any one of a number of known printhead modules and ink supply systems may be suitable for use with the present invention and thus further description of such features is omitted here. Details of printhead modules and ink supply systems suitable for use with the invention can be found in the co-pending applications listed at the start of this specification. 
     A scanner head  61  is incorporated into the lower molding  11  and receives power and transmits signal data via the flexible printed circuit board  34 . The scanner head  61  can be any conventional or new scanner head suitable for portable hand-held scanning. 
     A print controller  36  (not shown) includes a microprocessor that converts image data stored in a printer-scanner memory into a sequence of electrical “drop ejection” signals. The signals are communicated to the printhead module  30  in a known manner during a print operation to cause selective ejection of ink from the ink ejection nozzles  31 . 
     The printer-scanner memory would typically receive image data via the flexible printed circuit board  34  from the scanner head  61 . 
     The print controller  36  can also communicate with external devices to receive print instructions, in particular digital image data. In the embodiment shown, digital image data may be provided to the print controller  36  as an infra-red (IR) signal through an IR receiver window  37  formed in one end panel of the printer-scanner  10 . The IR receiver  37  which is electrically connected to the print controller microprocessor  36  receives the data which is then stored in the memory. In alternative embodiments (not shown), the print controller microprocessor may communicate through any other suitable connection for example, hard wire connections to other electronic devices (such as computers, scanners, copiers, digital cameras and the like), wireless telecommunications (such as WAP and the like) or through a plug and socket connection or data port. Other information, for example print control instructions, may also be provided to the printer-scanner from external devices using the above systems. In a further embodiment, the print controller microprocessor may have its own graphics generating capabilities. 
     The upper and lower mouldings provide a recess in which to receive batteries  42 , for example two 1.5 V “AAA” batteries. A flexible printed circuit board (PCB)  34  has busbars (not shown) thereon that convey power from the batteries  42  to the printhead module  30 , the print controller microprocessor  36  and any other powered components. 
     A power switch  43  formed in an end panel of the printer-scanner  10  is operated by a user to actuate the printer-scanner between powered and unpowered modes. 
     The batteries  42  are removable from the printer-scanner  10  through an aperture  46  formed between the upper and lower mouldings. The ink cartridge may be removed and replaced through a similar aperture  47 . As illustrated in  FIG. 3 , the end cap  13  is first removed from the printer-scanner  10  to reveal the apertures  46 ,  47  after which the batteries and/or ink cartridge may be replaced. In a further embodiment not illustrated here, the batteries and ink cartridge may be provided as an integral unit within a removable housing with only one aperture being formed in the end of the printer-scanner  10  to receive the housing. 
     A plurality of status indicating light emitting diodes (LEDs)  49   a ,  49   b ,  49   c  ( FIG. 4 ) are electrically connected to the microprocessor and are disposed in an outer surface of the printer-scanner  10 . The separate LEDs can be used for indicating error conditions such as low battery, low ink or general printer-scanner operation error conditions as well as a general printer-scanner ON/OFF condition. 
     To form the scanning operation, a user first switches the device on using the power switch  43 . A “scan” button can then be depressed or the device manipulated in some other way so as to switch it into a scanning mode. It can then be drawn over an image as shown in  FIG. 1  such that the scanning head  61  scans the pre-printed image  22  for storage in an on-board memory chip or the like. 
     To perform printing, a user first actuates the capping device  50 , in a manner described below, to expose the printhead chip  31  ( FIG. 5 ) to the print media. The print media may be any suitable textile for receiving the type of ink stored in the printer-scanner and may include inter alia paper, cardboard, wood, fabric and plastics. The printer-scanner  10  may include further control buttons depressed by the user to initiate printing, i.e. to commence the ejection of ink from the printhead under the control of the print control microprocessor. Alternatively, actuation of the capper  16  may be detected as a signal that the user is ready for the printing to commence. The user then traverses the print media  20  with the printer-scanner  10  as illustrated in  FIG. 2 . 
     To control the printing rate, the printer-scanner  10  includes an optical encoder wheel  39  ( FIG. 3 ) attached to the printhead module  30  at one end thereof. The optical encoder wheel  39  is received in slots  41   a ,  41   b  formed in the upper and lower mouldings respectively and extends from the mouldings to the point where the rim of the wheel  39  is level with the media slides  14  (see  FIG. 5 ). Circumferentially spaced markings on the optical encoder wheel  39  are read by an optical sensor as the wheel  39  rotates. 
     The optical sensor includes a light source, eg. an LED, and a photo-detector that produces an electrical response dependant on the amount of light incident upon the detector. The light reflection characteristics of the encoder wheel  39  vary between the marked and un-marked areas and thus as the markings rotate past the detector, a change in the detector response occurs. The frequency at which the detector responds provides a measurement of the speed at which the encoder wheel is rotating. The detector response is communicated to the print control microprocessor  36  which uses the signal to calculate the speed at which the printhead module is being moved across the print media. The print controller then synchronises the rate at which the drop ejection control signals are passed to the ink ejection nozzles with the measured speed at which the printer-scanner is moving. The printer-scanner  10  is therefore able to ensure appropriate print dot spacing of successive lines of print and thus create a faithful reproduction of the printed image even though the printer-scanner does not control the speed at which the print media moves relative to the printhead. 
     Furthermore, if the number of markings on the encoder wheel  39  is high enough, the microprocessor  36  is able to quickly adapt to the variations in the speed at which a user may move the printer-scanner across the print media thereby achieving a higher quality image. 
     In a similar way, the optical encoder wheel  39  may be functionally associated with the scanner head  61  if necessary to synchronise the rate of scanning with the rate at which the device is drawn over the pre-printed image. 
     An idler wheel  44  is attached to the opposite end of the printhead module  30  to allow stability and directional control of the printer-scanner. A shaft may connect the idler wheel  44  with the encoder wheel  39  to synchronise the rotation speeds of each wheel and therefore maintain a correct and straight-line tracking of the device over a page. 
     The optical encoder wheel  39  or idler wheel  44  may have a speed limiter such as a friction clutch that prevents a user from moving the printer-scanner along the print media at a rate faster than the maximum rate of operation of the printhead module  30 . Furthermore, either or both wheels may have a system such as a ratchet for preventing the printer-scanner from being moved in reverse to the direction of printing. 
     Operation of the capping mechanism  50  is described in our co-pending application having docket No. AP44 filed concurrently herewith and entitled “Printer with Capping Device”. 
     A contact sensor (not shown) may detect when the capper  50  is moved to the uncapped position and communicate the state of the capper to the print control microprocessor  36  so that printing is only attempted when the capper  50  is in the uncapped position. 
     The printer-scanner  10  of the present invention may include keys for controlling the microprocessor to perform such printer-scanner operations as downloading image data from an external device, resetting an incomplete print operation so that the printer-scanner commences printing at the start of an image and the like. Alternatively, these functions may be communicated to the printer-scanner through the IR data port described previously.