Abstract:
A method for improving human interaction with a printer and its hardcopy output. The method comprises printing a first page and placing it into an output bin followed with a pause to allow for full drying of the print. However, this pause will be interrupted if the page is removed from the output bin and thereby expedite any subsequent printing output that may be queued follow.

Description:
BACKGROUND OF THE INVENTION AND MATERIAL DISCLOSURE STATEMENT 
     The present invention relates to a methodology for expediting the handling of print job output in the output bin of a printer. In particular, the present invention relates to where ink drying time is a concern that must be considered, as found for example with ink jet printers. 
     Ink jet printers have become very popular particularly for providing color print output. This has much to do with the economy of their production and therefore end cost to the consumer. Much of this economy has to do with inks that are used allow a relatively inexpensive hardware configuration. However, the inks used typically have a finite drying time which is slower than other types of printers. Much effort has been expended in overcoming the problems that arise from this limitation including developing faster dry inks. One such early approach was to simply take advantage of a slower print rate which would allow sufficient drying time between pages of printout. Where faster output is demanded this is a limitation to throughput. One approach as practiced by Hewlett Packard in U.S. Pat. No. 4,728,963 to Rasmussen et al., and incorporated in its entirety for its teaching, involves using collapsible support rails which hold the most recent page of printout above the output stack. It then drops that most recent page prior to another page of printout arriving for the output bin. This effectively increases the drying time and helps avoid one page sticking to another. This also helps with offset problems, where ink from the front of one page is transferred to the back of another page. 
     Another approach which is taken to solve ink drying time problems is to put a pause in the printing of a subsequent page until there is sufficient time for the drying of the current page. This time varies depending upon the page material. For example, transparencies need a considerably longer drying time so it is common for long pauses to be utilized in their printing. This considerably slows output and can be particularly frustrating when last minute transparencies are needed for a meeting or presentation. 
     Therefore, as discussed above there exists a need for a methodology which will solve the problem of page delays due to drying concerns before which subsequent pages may print. Thus, it would be desirable to solve this and other deficiencies and disadvantages with an improved methodology. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a method for a printer of the liquid ink type requiring a finite drying time for the ink to provide printout to its output bin. The method comprises outputting a current page to the output bin and pausing the output of a subsequent page for a fixed period of time. The printer shall output the subsequent page if the current page is removed from the output bin before the fixed period of time has passed. 
     Further, the present invention relates to a method for a ink jet printer to provide printout to its output bin, comprising outputting a current page to the output bin and pausing the output of a subsequent page until at least one of the following two conditions has been met. A fixed period of time has elapsed or, the current page has been removed from the output bin. 
     More particularly, the present invention relates to a method for an ink jet printer to provide printout to its output bin, comprising outputting a current page to the output bin and setting a pause counter. This is followed by stepping the pause counter and then determining if the current page has been removed from the output bin. The last step is outputting the subsequent page if the current page has been removed from the output bin or, if not, stepping the pause counter if the current page has not been removed from the output bin. The determination and this last step are repeated until the counter times out or the page is removed, which ever comes first. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 depicts a typical printer with a output bin sensor. 
     FIG. 2 shows schematic block diagram of on possible hardware configuration for the present invention. 
     FIG. 3 depicts a simplified flow chart of a prior art approach to achieving acceptable drying times. 
     FIG. 4 depicts a flow chart for the present invention which makes allowance for an output bin sensor. 
    
    
     DESCRIPTION OF THE INVENTION 
     FIG. 1 provides an ink jet printer  10 . There, it will be observed that a paper input or supply tray  12  is provided in the front, or user-facing portion,  14  of the printer  10 . The paper input tray  12  is configured to handle a substantial quantity of paper  16   a  or other medium for printing thereon. Also in the front  14  of the printer  10  is provided a paper output or collection tray  18 . The paper output tray  18  is also configured to handle a substantial quantity of paper  16   b.    
     There are two features to be noticed with regard to the paper output tray  18 . First, an output bin sensor  20  is provided near the rear of the paper output tray  18 . Sensor  20  is provided for indication of whether the user has removed the previous page or output paper  16   b.  The operation of sensor  20  may be based for example upon sensing weight, light scattering or light reflectance effects from when paper  16   b  is present or not in collection tray bin  18 . In a preferred embodiment, an inexpensive simple LED detector pair is used that can detect either a reflectance or a scattering signal. Thus both transparencies and paper can be detected. Many other arrangements will be conceivable to those skilled in the art and as such are considered within the gambit of the present invention. It should be noted for instance that there are many arrangements for providing this sensor functionality including its placement location in the output bin. For example, many printer systems already have a sensor provided at the output for the purpose of tracking paper jams. Such arrangements may be utilized with the present invention with little or even no modification as would be evident to one skilled in the art. 
     Second, a pair of opposed output rails  22  is provided above the output tray  18 . These output rails  22  along with the platen (not visible in this view) support a sheet of paper  16   c  during the printing operation to permit the ink on the sheet  16   b  underneath to dry. At the end of the printing cycle, when the sheet  16   c  is near the front  14   a  of the paper output tray  18 , the platen pivots down, eliminating the clamping of the sheet between the platen and paper guide  27 . The sheet  16   c  then drops into the paper output tray of its own weight. Up until the completion of the printing cycle, the rear end of the paper is supported by the paper drive roller and the platen. 
     The front portion  14  of the printer  10  is also provided with a control panel  28 , which is electrically associated with a microprocessor/controller  200  (FIG. 2) for selection of various options relating to the printing operation. Such control operations, provided by presently-available microprocessors, are well-known in the prior art. 
     Also shown in FIG. 1 is a printhead carriage  35 , which travels on a guide rail  34  and paper guide  27 , and printhead  32  which is connected by a flexible electrical flat ribbon  36  to the microprocessor/controller  200 . The microprocessor/controller  200  controls a motor, which provides movement of the printhead carriage  35 . The printhead  32  is specifically designed for this ink-jet printer, and utilizes thermal ink-jet printing technology. However, the printer could operate with other ink-jet printheads if the printhead carriage interfaces are compatible, or with other carriage configurations. Further, reconfiguration of the printhead carriage  32  would permit the use of other ink-jet technologies, such as piezoelectric. Such reconfiguration is within the capabilities of one skilled in the art. 
     FIG. 2 provides a concise schematical representation of a preferred embodiment. Controller  200  is coupled with output bin sensor  20 . In a preferred embodiment controller  200  polls for an indicator from sensor  20 . When sensor  20  indicates that the printout has been removed from the output bin the controller  200  executes a decision to end a counter/timer loop and proceed directly to the printing of the new page of hardcopy if any. As such the controller  200  may now direct the paper feeder  220  or platen to advance the present page and allow it to drop from rails  22 . 
     In an alternative embodiment, the signal indication of printout removal from output bin by sensor  20  is handled by the controller  200  as an interrupt. Those skilled in the art will understand what software changes are necessary for that scenario. Indeed, there are many other hardware and software specifics which will yield the same result, including for example custom logic circuits dedicated to implementing the logic flow discussed below. 
     FIG. 3 depicts one probable flow chart of the prior art approach taken in a typical ink jet printer. Block  300  represents the print page command. Typically when a print page command is made a determination of the printout type is made and there by the amount of pause time required. For example, when a transparency is to be generated, a greater pause time is required to allow for the ink drying on that media type. Paper may need little or no additional time for drying. This determination of the amount of pause then sets the delay in block  310 . This is typically a count-up or a count-down counter although other approaches may be taken such as executing different loops of no-ops (no operation micro-code instructions) as will be evident to those skilled in the art. 
     A preferred embodiment of the invention, as shown in FIG. 4, also starts with the same print page command  300  block. However, a determination of counter setting is made at block  400 . The counter in this embodiment is an incrementing type which counts up to a specified number before triggering for a new page. Block  410  increments the counter for each loop iteration. After action block  410  executes, the next logic step is decision block  420 . Here the sensor  20  signal is checked to see if there is indication that the hardcopy printout  16   b  has been removed from the output tray  18 . If it has then the increment counter  410  is bypassed and the next page is printed. If not then the counter is incremented and the decision block  420  addressed again until either the counter reaches the specified number and times out, or the printout  16   b  is removed, which ever happens first. The purpose here is that either a time out or pickup of printout will invoke a new print page  300 . Those skilled in the art will recognize there are any number of other approaches to achieve this same logic flow result. 
     In summary, practicing the methodology of the present invention reduces the amount of time required to generate hardcopy output when human attendance is available to intervene in the ink drying cycle. By providing a sensor at the output bin or making use of one already there, intelligence may be provided with a small amount of additional code in the controller. This allows a less frustrating experience for an end user who, if anxious for printout, is willing to remove the current printout and allow it to dry elsewhere. Furthermore, 
     While the embodiment disclosed herein is preferred, it will be appreciated from this teaching that various alternative, modifications, variations or improvements therein may be made by those skilled in the art, which are intended to be encompassed by the following claims.