Abstract:
A compact printer having a printhead, a powered roller and a novel capping mechanism. The printhead prints on printable media that is passed adjacent to the printhead by the powered rollers. The capping mechanism has a pair of spaced apart capping arms that are bridged by a cap. The cap is moved between a position that protects the printhead and a position that enables the printhead to print on the media. The powered roller causes the capping arms to be moved between these positions and also moves the printable media past the printhead between the cap and the printhead.

Description:
FIELD OF THE INVENTION 
     The invention relates to a compact printer system able to print full-color, business card size documents from a device about the size of a pen. The system includes various hot-connectable modules that provide a range of functions. In particular the invention relates to a capping mechanism to prevent ink drying in the printer. 
     Reference may be had to co-pending applications claiming priority from Australian Provisional Patent Application number PQ0560 dated May 25, 1999. The co-pending applications describe related modules and methods for implementing the compact printer system. The co-pending applications are as follows: 
     
       
         
               
               
               
             
           
               
                   
                   
               
               
                   
                 USSN 
                 Docket No. 
               
               
                   
                   
               
             
             
               
                   
                 09/575,182 
                 PP01 
               
               
                   
                 09/575,173 
                 PP02 
               
               
                   
                 09/575,136 
                 PP04 
               
               
                   
                 09/575,119 
                 PP07 
               
               
                   
                 09/575,135 
                 PP08 
               
               
                   
                 09/575,157 
                 PP09 
               
               
                   
                 09/575,166 
                 PP10 
               
               
                   
                 09/575,134 
                 PP11 
               
               
                   
                 09/575,121 
                 PP12 
               
               
                   
                 09/575,137 
                 PP13 
               
               
                   
                 09/575,167 
                 PP15 
               
               
                   
                 09/575,120 
                 PP16 
               
               
                   
                 09/575,122 
                 PP17 
               
               
                   
                   
               
             
          
         
       
     
     BACKGROUND OF THE INVENTION 
     Microelectronic manufacturing techniques have led to the miniaturization of numerous devices. Mobile phones, personal digital assistant devices, and digital cameras are very common examples of the miniaturization trend. 
     One device that has not seen the advantage of microelectronic manufacturing techniques is the printer. Commercially available printers are large compared to many of the devices they could support. For instance, it is impractical to carry a color printer for the purpose of instantly printing photographs taken with known compact digital cameras. 
     A compact printhead has been described in co-pending United States Patent Applications filed simultaneously to the present application and hereby incorporated by cross reference: 
     
       
         
               
               
               
             
           
               
                   
                   
               
               
                   
                 USSN 
                 Docket No. 
               
               
                   
                   
               
             
             
               
                   
                 09/575,152 
                 MJ62 
               
               
                   
                 09/575,141 
                 IJ52 
               
               
                   
                 09/575,125 
                 IJM52 
               
               
                   
                 09/575,176 
                 MJ63 
               
               
                   
                 09/575,147 
                 MJ58 
               
               
                   
                   
               
             
          
         
       
     
     Most color printers use ink for printing. The ink is selectively delivered through nozzles forming part of the printhead. Ink drying in the ink nozzles is a common problem with ink jet printers. It is, known to provide a cap for the nozzles to substantially prevent evaporation and thereby minimize the problems of dry ink blocking the nozzles. The problem causes particular difficulties in a compact printer due to the inaccessibility of the printhead. The known capping mechanisms obstruct the paper path in printers having a stationary printhead and moving paper. While cleaning remains an option, it is preferable to prevent the problem of dry ink as far as possible. 
     SUMMARY OF THE INVENTION 
     In one form, the invention resides in a nozzle capping mechanism for a printhead of a compact printer having a powered roller for moving printable media past said printhead, said mechanism comprising: 
     at least one capping arm operativy associated with the powered roller; and 
     a cap supported by said capping arm and movable with said capping arm between a position engaging the printhead and a position spaced from said printhead; 
     wherein said cap rests in contact with said printhead and the capping arm moves said cap away from said printhead when said powered roller rotates. 
     Further features of the invention will be evident from the following description. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order to assist with describing preferred embodiments of the invention, reference will be made to the following figures in which: 
     FIG. 1 is a printer module; 
     FIG. 2 is a camera module; 
     FIG. 3 is a memory module; 
     FIG. 4 is a communication module; 
     FIG. 5 is a flash module; 
     FIG. 6 is a timer module; 
     FIG. 7 is a laser module; 
     FIG. 8 is an effects module; 
     FIG. 9 is a characters module; 
     FIG. 10 is an adaptor module; 
     FIG. 11 is a pen module; 
     FIG. 12 is a dispenser module; 
     FIG. 13 is a first compact printer configuration; 
     FIG. 14 is a second compact printer configuration; 
     FIG. 15 is a third compact printer configuration; 
     FIG. 16 is a fourth compact printer configuration; 
     FIG. 17 is an exploded view of the Printer Module of FIG. 1; 
     FIG. 18 is a top view of the Printer Module with ink cartridge removed; 
     FIG. 19 is a cross-sectional view through AA in FIG. 18; 
     FIG. 20 is an embodiment of a nozzle capping mechanism; and 
     FIG. 21 shows the embodiment of FIG. 20 in an uncapped state; 
     FIG. 22 shows the underside of the drive assembly of the Printer Module of FIG. 1; and 
     FIG. 23 shows a top three quarter view of the drive assembly of FIG.  22 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIGS. 1 to  12 , there are shown various modules that together form a compact printer system. Individual modules can be attached and detached from the compact printer configuration to allow a user-definable solution to business-card sized printing. Images can also be transferred from one compact printer to another without the use of a secondary computer system. Modules have a minimal user-interface to allow straightforward interaction. 
     A compact printer system configuration consists of a number of compact printer modules connected together. Each compact printer module has a function that contributes to the overall functionality of the particular compact printer configuration. Each compact printer module is typically shaped like part of a pen, physically connecting with other compact printer modules to form the complete pen-shaped device. The length of the compact printer device depends on the number and type of compact printer modules connected. The functionality of a compact printer configuration depends on the compact printer modules in the given configuration. 
     The compact printer modules connect both physically and logically. The physical connection allows modules to be connected in any order, and the logical connection is taken care of by the compact printer Serial Bus—a bus that provides power, allows the modules to self configure and provides for the transfer of data. 
     In terms of physical connection, most compact printer modules consist of a central body, a male connector at one end, and a female connector at the other. Since most modules have both a male and female connector, the modules can typically be connected in any. order. Certain modules only have a male or a female connector, but this is determined by the function of the module. Adaptor modules allow these single-connector modules to be connected at either end of a given compact printer configuration. 
     A four wire physical connection between all the compact printer modules provides the logical connection between them in the form of the compact printer Serial Bus. The compact printer Serial Bus provides power to each module, and provides the means by which data is transferred between modules. Importantly, the compact printer Serial Bus and accompanying protocol provides the means by which the compact printer system auto-configures, reducing the user-interface burden on the end-user. 
     Compact printer modules can be grouped into three types: 
     image processing modules including a Printer Module (FIG.  1 ), a Camera Module (FIG.  2 ), and a Memory Module (FIG.  3 ). Image processing modules are primarily what sets the compact printer system apart from other pen-like devices. Image processing modules capture, print, store or manipulate photographic images; 
     housekeeping modules including an Adapter Module (FIG.  10 ), an Effects Module (FIG.  8 ), a Communications Module (FIG.  4 ), and a Timer Module (FIG.  6 ). Housekeeping modules provide services to other modules or extended functionality to other modules; and 
     isolated modules including a Pen Module (FIG. 11) and a Laser Module (FIG.  7 ). Isolated modules are those that attach to the compact printer system but are completely independent of any other module. They do not necessarily require power, and may even provide their own power. Isolated Modules are defined because the functionality they provide is typically incorporated into other pen-like devices. 
     Although housekeeping modules and isolated modules are useful components in a compact printer system, they are extras in a system dedicated to image processing and photographic manipulation. Life size (1:1) illustrations of the compact printer modules are shown in FIGS. 1 to  12 , and example configurations produced by connecting various modules together are shown in FIGS. 13 to  16 . 
     FIG. 1 shows a printer module that incorporates a compact printhead described in co-pending United States Patent Applications listed in the Background section of this application, incorporated herewith by reference, and referred to herewith as a Memjet printhead. The Memjet printhead is a drop-on-demand 1600 dpi inkjet printer that produces bi-level dots in up to 4 colors to produce a printed page of a particular width. Since the printhead prints dots at 1600 dpi, each dot is approximately 22.5 μm in diameter, and spaced 15.875 μm apart. Because the printing is bi-level, the input image should be dithered or error-diffused for best results. Typically a Memjet printhead for a particular application is page-width. This enables the printhead to be stationary and allows the paper to move past the printhead. A Memjet printhead is composed of a number of identical ½ inch Memjet segments. 
     The printer module  10  comprises a body  11  housing the Memjet printhead. Power is supplied by a three volt battery housed in battery compartment  12 . The printhead is activated to commence printing when a business card (or similar sized printable media) is inserted into slot  13 . Male connector  14  and female connector  15  facilitate connection of other modules to the printer module  10 . 
     FIG. 2 shows a camera module  20 . The camera module provides a point-and-shoot camera component to the compact printer system as a means of capturing images. The camera module comprises a body  21  having a female connector  22 . A lens  23  directs an image to an image sensor and specialized image processing chip within the camera  24 . A conventional view finder  25  is provided as well as a lens cap  26 . An image is captured when the Take button  27  is pushed. Captured images are transferred to the Printer Module  10  for subsequent printing, manipulation, or storage. The Camera Module also contains a self-timer mode similar to that found on regular cameras. 
     FIG. 3 shows a Memory Module  30  comprising a body  31 , LCD  32 , IN button  33 , OUT button  34  and SELECT button  35 . The Memory Module  30  is a standard module used for storing photographic images, captured by the Camera  20 . The memory module stores  48  images, each of which can be accessed either at full resolution or at thumbnail resolution. Full resolution provides read and write access to individual images, and thumbnail resolution provides read access to 16 images at once in thumbnail form. 
     The Memory Module  30  attaches to other modules via a female connector  36  or male connector  37 . The male and female connectors allow the module to be connected at either end of a configuration. Power is provided from the Printer Module  10  via the Serial Bus. 
     A Communications Module  40  is shown in FIG.  4 . The communications module  40  consists of a connector  41  and a cable  42  that terminates in an appropriate connector for a computer port, such as a USB port, RS232 serial port or parallel port. The Communications Module  40  allows the compact printer system to be connected to a computer. When so connected, images can be transferred between the computer and the various modules of the compact printer system. The communications module allows captured images to be downloaded to the computer, and new images for printing to be uploaded into the printer module  10 . 
     A Flash Module  50  is shown in FIG.  5 . The Flash Module  50  is used to generate a flash with flash cell  51  when taking photographs with the Camera Module  20 . The Flash Module attaches to other modules via female connector  52  and male connector  53 . It contains its own power source. The Flash Module is automatically selected by the Camera Module when required. A simple switch allows the Flash Module to be explicitly turned off to maximize battery life. 
     FIG. 6 shows a Timer Module  60  that is used to automate the taking of multiple photos with the Camera Module  20 , each photo separated by a specific time interval. The captured photos are stored in Memory Module  30 . Any flash requirements are handled by the Camera Module  20 , and can therefore be ignored by the Timer Module. The Timer Module  60  consists of a body  61  housing a LCD  62 , START/STOP button  63  and UNITS button  64 . A SELECT button  65  allows the user to select time units and the number of units are set by UNITS button  64 . The Timer Module  60  includes a male connector  66  and female connector  67 . The Timer Module takes its power from the Printer Module  10  via the Serial Bus. 
     A Laser Module  70  is shown in FIG.  7 . The Laser Module  70  consists of a body  71  containing a conventional laser pointer operated by button  72 . As the Laser Module is a terminal module it only has one connector, which in the example is a male connector  73 . The Laser Module is an isolated module, in that it does not perform any image capture, storage, or processing. It exists as a functional addition to the compact printer system. It is provided because laser pointer services are typically incorporated into other pen-like devices. The Laser Module contains its own power supply and does not appear as a device on the Serial Bus. 
     The Effects Module shown in FIG. 8 is an image processing module. It allows a user to select a number of effects and applies them to the current image stored in the Printer Module  10 . The effects include borders, clip-art, captions, warps, color changes, and painting styles. The Effects Module comprises a body  81  housing custom electronics and a LCD  82 . A CHOOSE button  83  allows a user to choose between a number of different types of effects. A SELECT button  84  allows the user to select one effect from the number of effects of the chosen type. Pressing the APPLY button  85  applies the effect to image stored in the Printer Module  10 . The Effects Module obtains power from the Serial Bus. Male connector  86  and female connector  87  allow the Effects Module to be connected to other compact printer system modules. 
     FIG. 9 shows a Character Module  90  that is a special type of Effects Module (described above) that only contains character clip-art effects of a given topic or genre. Examples include The Simpsons®, Star Wars®, Batman®, and Dilbert® as well as company specific modules for McDonalds® etc. As such it is an image processing module. It consists of a body  91  housing custom electronics and a LCD  92 . SELECT button  93  allows the user to choose the effect that is to be applied with APPLY button  94 . The Character Module obtains power from the Serial Bus through male connector  95  and female connector  96 . 
     The Adaptor Module  100 , shown in FIG. 10, is a female/female connector that allows connection between two modules that terminate in male connectors. A male/male connector (not shown) allows connection between two modules that terminate in female connectors. The Adaptor Module is a housekeeping module, in that it facilitates the use of other modules, and does not perform any specific processing of its own. 
     All “through” modules have a male connector at one end, and a female connector at the other end. The modules can therefore be chained together, with each module connected at either end of the chain. However some modules, such as the Laser Module  70 , are terminating modules, and therefore have either a male or female connector only. Such single-connector modules can only be connected at one end of the chain. If two such modules are to be connected at the one time, an Adaptor Module  100  is required. 
     FIG. 11 shows a Pen Module  110  which is a pen in a module form. It is an isolated module in that it attaches to the compact printer system but is completely independent of any other module. It does not consume or require any power. The Pen Module is defined because it is a convenient extension of a pen shaped, pen sized device. It may also come with a cap  111 . The cap may be used to keep terminating connectors clean in the case where the chain ends with a connector rather than a terminating module. 
     To assist with accurately feeding a business card sized print media into slot  13  of the printer module  10 , a dispenser module  120  is provided as shown in FIG.  12 . The dispenser module  120  comprises a body  121  that holds a store of business card sized print media. A Printer Module  10  locates into socket  122  on the dispenser module  120 . When correctly aligned, a card dispensed from the dispenser module by slider  123  enters slot  13  and is printed. 
     In the sense that a minimum configuration compact printer system must be able to print out photos, a minimum compact printer configuration contains at least a Printer Module  10 . The Printer Module holds a single photographic image that can be printed out via its Memjet printer. It also contains the 3V battery required to power the compact printer system. 
     In this minimum configuration, the user is only able to print out photos. Each time a user inserts a business card  130  into the slot in the Printer Module, the image in the Printer Module is printed onto the card. The same image is printed each time a business card is inserted into the printer. In this minimum configuration there is no way for a user to change the image that is printed. The dispenser module  120  can be used to feed cards  130  into the Printer Module with a minimum of fuss, as shown in FIG.  13 . 
     By connecting a Camera Module  20  to the minimum configuration compact printer system the user now has an instant printing digital camera in a pen, as shown in FIG.  14 . The Camera Module  20  provides the mechanism for capturing images and the Printer Module  10  provides the mechanism for printing them out. The battery in the Printer Module provides power for both the camera and the printer. 
     When the user presses the “Take” button  27  on the Camera Module  20 , the image is captured by the camera  24  and transferred to the Printer Module  10 . Each time a business card is inserted into the printer the captured image is printed out. If the user presses “Take” on the Camera Module again, the old image in the Printer Module is replaced by the new image. 
     If the Camera Module is subsequently detached from the compact printer system, the captured image remains in the Printer Module, and can be printed out as many times as desired. The Camera Module is simply there to capture images to be placed in the Printer Module. 
     FIG. 15 shows a further configuration in which a Memory Module  30  is connected to the configuration of FIG.  14 . In the embodiment of FIG. 15, the user has the ability to transfer images between the Printer Module  10  and a storage area contained in the Memory Module  30 . The user selects the image number on the Memory Module, and then either sends that image to the Printer Module (replacing whatever image was already stored there), or brings the current image from the Printer Module to the specified image number in the Memory Module. The Memory Module also provides a way of sending sets of thumbnail images to the Printer Module. 
     Multiple Memory Modules can be included in a given system, extending the number of images that can be stored. A given Memory Module can be disconnected from one compact printer system and connected to another for subsequent image printing. 
     With the Camera Module  20  attached to a Memory Module/Printer Module compact printer system, as shown in FIG. 15, the user can “Take” an image with the Camera Module, then transfer it to the specified image number in the Memory Module. The captured images can then be printed out in any order. 
     By connecting a Communications Module  40  to the minimum configuration compact printer system, the user gains the ability to transfer images between a PC and the compact printer system. FIG. 16 shows the configuration of FIG. 15 with the addition of a Communications Module  40 . The Communications Module makes the Printer Module  10  and any Memory Modules  30  visible to an external computer system. This allows the download or uploading of images. The communications module also allows computer control of any connected compact printer modules, such as the Camera Module  20 . 
     In the general case, the Printer Module holds the “current” image, and the other modules function with respect to this central repository of the current image. The Printer Module is therefore the central location for image interchange in the compact printer system, and the Printer Module provides a service to other modules as specified by user interaction. 
     A given module may act as an image source. It therefore has the ability to transfer an image to the Printer Module. A different module may act as an image store. It therefore has the ability to read the image from the Printer Module. Some modules act as both image store and image source. These modules can both read images from and write images to the Printer Module&#39;s current image. 
     Detailed views of the Printer Module  10  are shown in FIGS. 17 and 18. The Printer Module  10  is the central. module in the compact printer system. It contains a 2-inch Memjet printhead  16 , a Cyan/Magenta/Yellow ink cartridge  17 , the current image, stored in flash memory on the printhead and a power source in the form of a 3V battery  12   a  in the battery compartment  12 . With regards to processing, the Printer Module  10  contains a controller  101  that incorporates an image processing chip to print the stored image in high quality, and a QA chip for ensuring the ink cartridge  17  does not run dry. 
     The Printer Module  10  can, be used as a stand-alone printer of a single image (such as business cards), or can be used in conjunction with other modules to print a variety of images. 
     Looking in detail at FIG. 17, the body  11  of the printer module is in three parts being a lid  11   a , base  11   b  and chassis  11   c . Printhead  16  with filter  16   a  fits into the chassis  11   c . Powered rollers  18   a  are driven by motor and gearbox  103 . Neutral rollers  18   b  fit into ink cartridge  17  and guide a card past the printhead  16 . Springs  18   c  (FIG. 19) urge the neutral rollers  18   b  towards the powered rollers  18   a . The ink cartridge  17  is located beyond the rollers  18  so that the card passes between the printhead  16  and the ink cartridge  17 . Ink inlets  105  provide communication between the ink cartridge  17  and the printhead  16 . Micro-moulded channels  106  in the chassis  11   c  distribute the ink from the ink inlets  105  to the length of the printhead  16 . 
     Serial bus  104  provides power and data between the printer module  10  and other modules connected to male connector  14  and female connector  15 . The serial bus  104  picks up power from the battery  12   a  and signals from the controller  101 . 
     Looking at FIG. 19, to print an image, a user simply inserts a business card into the input slot  13  of the Printer Module. Sensor  102  detects the insertion and the motor and gearbox  103  activates powered rollers  18   a  to carry the card through the module with neutral rollers  18   b . A tab film  107  provides signal connection from the sensor  102  to the controller  101  and hence to the motor and gearbox  103 . A wedge  108  holds the tab film  107  against the controller  101  to make a signal connection. 
     The printed card is ejected from the output slot  13   a  of the module over a time period of 1 second. There is no on/off switch—the act of inserting the card is the effective “on” switch for the duration of a print. 
     To reduce the chance of ink drying in the printhead  16  a capping mechanism  19  is provided to cap the ink nozzles in the printhead. The capping mechanism  19  comprises a capping arm  191  supporting a cap in the form of adjacent elastomeric seals  193 . The elastomeric seals are suitably formed as a continuous elastomeric ring that is glued to the end of the capping arm. A blotter  192  is located at the end of the capping arm between the seals. The blotter soaks up ink ejected from the printhead during cleaning. 
     As shown in FIGS. 20 to  23 , a drive gear  194  is operatively associated with both of the powered rollers  18   a  to move the capping arm.  191  out of the path of the card for printing. The drive gear  194  is driven directly by the motor  103   a  and powers both drive rollers  18   a . The capping arm  191  is moved away from the printhead  16  when a reversing gear assembly  203  is activated. The reversing gear assembly consists plastic molded housing  204  and two gears. The longer transmission gear  205  engages with the main drive gear  194  and in one direction powers the second smaller reversing gear  206  around to make contact with gear on the end of the capping arm  201 . These act together to pivot the capping arm away and uncap the printhead  16 . When printing is finished, the main gear  194  is reversed, which reverses the drive rollers and pivots the capping arm  191  to the home position after it is engaged by the reversing gear assembly  203 . It rotates back towards the printhead  16  until the elastomeric seals  193  seal either side of the printhead  16 . The elastomeric seals  193  maintain a moist environment in the vicinity of the printhead. 
     As shown in FIGS. 20 to  23 , the ink cartridge  17  is shaped to receive the capping arm  191  out of the path of the printable media. There is a capping arm at each end of the printhead with the cap extending between the capping arms. Each capping arm is separated by a space sufficient to allow the passage of the card being printed. 
     Throughout the specification the aim has been to describe the preferred embodiments of the invention without limiting the invention to any one embodiment or specific collection of features. Persons skilled in the relevant art may realize variations from the specific embodiments that will nonetheless fall within the scope of the invention.