METHOD AND APPARATUS FOR CALIBRATING A PAPER SENSOR TO ACCOUNT FOR MEDIA HOLES

The image forming device includes an image forming section in which an image is formed on the prepunched paper; a paper feed path through which paper is fed to and from the image forming section during a process in which an image is formed on the paper; one or more sensors arranged along the paper feed path to monitor a flow of the prepunched paper as it is fed through the paper feed path; and a processor for receiving signals from the sensors and map data of the prepunched paper, and for analyzing the signals and the map data to determine if there is a paper jam along the paper feed path, wherein the map data indicates locations of all holes, cut-outs, and notches formed in the prepunched paper. A method of using the image forming device is also disclosed.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A system has now been developed to avoid or minimize the aforementioned issues concerning the use of sensors with a paper30or recording medium having holes40, notches, or cut-outs formed therein, hereinafter referred to as prepunched paper.

FIG. 5is a flowchart that illustrates the basic mapping operation of an embodiment of the present invention. According to the embodiment ofFIG. 5, prior to running a print job using prepunched paper on an MFP20, an exemplary sheet of the prepunched paper30is scanned by the scanner10of the MFP20(step S110). The scanned prepunched paper is then mapped by the MFP20to identify the location of all such holes40, notches, and cut-outs formed in the prepunched paper (step S120). Further details of the mapping process are shown inFIG. 6. The map of the prepunched paper is then saved in a memory50in the MFP20(step S130). A label, such as “3 hole punch paper” is then assigned to the map (step S130) and saved with the map. If desired, the user can also assign a paper tray to the stored map and save the paper tray information together with the map name and data (step S140).

Mapping of the paper is illustrated inFIGS. 4 and 6. According to one embodiment, after the paper30is scanned in step S110, a first hole40is identified in the sheet of prepunched paper (step S210). Then, a smallest possible rectangular boundary60that can include all portions of the particular hole40is created (step S220). SeeFIG. 4.

Coordinates are then assigned to the rectangular boundary, e.g., (x1-x2; y1-y2) and saved (S230). The system then determines if there is another hole that has not yet been mapped (S240). If so, the process of identifying the hole, creating a boundary, assigning coordinates to such boundary, and saving the data is repeated for each hole or opening in the paper (YES at block S240). If all holes have been mapped (NO at block S240), the data is then saved to a memory. As indicated above with respect to the flowchart inFIG. 5, each map may then be labeled (S130) and, if desired, assigned to a specific paper tray (S140).

The map data can also include the overall dimensions of the paper, such as 8½ by 11 inches, or A4 size.

As an alternative, to creating the map on the MFP20, the map can be created by an external device and sent to the MFP20. Furthermore, for commonly used prepunched papers, such as that which is punched for a three ring binder, one or more maps can be made in advance and stored. For such common prepunched papers, the maps could be made in any manner and programmed into a memory. In such a case, it would not be necessary to scan the prepunched paper to determine the location of such holes.

Each of the individual steps or processes identified above, e.g., identifying the holes, creating boundaries for each hole, and assigning coordinates to the boundaries, can be done by any number of ways that would be readily known to one of ordinary skill in the art. Accordingly, detailed descriptions thereof are omitted.

Once the mapping process has been completed, the user can then run a print job using the mapped prepunched paper as illustrated inFIG. 7.

The first step for running the print job according is to load the image to be printed (S310). The image can be loaded in any number of conventional ways. For example, image data that is prestored in a memory70in the MFP20can be selected, for example using a display80on the MFP20. SeeFIG. 8. In an image selection box82, using selector84, the user can select from a drop down menu, which device is holding the image data to be printed. The selection of devices could include a number of external devices, the MFP scanner10, or a memory70in the MFP20. If the scanner10is selected, the image data can be created by scanning an original document using the scanner10of the MFP20. Once the device is selected, the user can select, using drop down menu86, the name of the file for the image data. One of ordinary skill in the art could create and use alternative methods of selecting and/or loading the device and/or image data.

Once the image data is identified and selected, the user then selects copy conditions from menus found in the copy conditions section88of the display80(step S320). Such copy conditions can include any number of known options, including but not limited to the number of pages, two-sided copying, magnification/reduction, etc. Because such features are all well known, details of the copy conditions section88are omitted.

Once the image data has been selected, and the copy conditions have been set, the user can then load a map from the map loading section90of the display80. For example, the map loading section90may include a drop down menu92from which the user can select a preloaded map of prepunched paper. The maps could include maps created according to the methods set forth above. According to one embodiment, the drop down menu92could include one option for whole paper, i.e., paper that is not prepunched.

As explained above, the mapped data could be stored and identified by reference to a particular paper tray in the MFP20. In that case, the user would simply identify the desired paper tray from the drop down menu92.

After the image data has been selected (step S310), the copy conditions have been set (S320), and the map data has been loaded (S330), the user may initiate the process using the start button94on the MFP display80. Once the start button94is pressed, the printer driver will send the print job, together with the map of the paper being used.

FIG. 9illustrates an embodiment of the present invention showing how the sensors use the paper map to avoid an inadvertent indication of a paper jam. In particular,FIG. 9shows how the sensors determine whether or not there is a paper jam. The flowchart ofFIG. 9relates to only one sensor74in the MFP20. However, the process is repeated for each sensor along the paper feed path76in the MFP20.

As the paper30begins moving through the paper feed path76, the light receiving portion of the sensor74is receiving light. As the leading edge of the paper30reaches the sensor74, the light receiving portion stops receiving light, thus forming the OFF EDGE of the sensor output (Step S410). If YES at S410, the sensor74detects the leading edge of the paper, and stores time T1(Step S420). When the trailing edge of the paper30passes the sensor74, the light receiving portion of the sensor again receives light (YES at S430), thus forming the ON EDGE of the sensor output, and time T2is stored (Step440). The system then calculates the difference between T2and T1, i.e., T2−T1=T3(Step S450). If T3matches with the expected time for the known paper size (YES at S460) then, it is determined that there is no paper jam, and the sensor74awaits the next shhet of paper. If T3does not match with the expected time for the known paper size (NO at S460) then, a check is made to see if T3matches with any openings in the paper that have been identified with the paper map (S480). If NO at S480, then it is determined that a paper jam exists. If YES at S480, the time T2is reset, and the sensor continues to wait for the next time the trailing edge passes the sensor (S490).

In this way, the aforementioned sensors can anticipate and account for holes, cut-outs, and/or notches in the paper being fed so as to minimize the likelihood of an erroneous indication of a paper jam during the printing process.

A CPU72in the MFP20can control the aforedescribed processes.

While the present invention may be embodied in many different forms, a number of illustrative embodiments are described herein with the understanding that the present disclosure is to be considered as providing examples of the principles of the invention and such examples are not intended to limit the invention to preferred embodiments described herein and/or illustrated herein. The present invention includes any and all embodiments having equivalent elements, modifications, omissions, combinations (e.g. of aspects across various embodiments), adaptations and/or alterations as would be appreciated by those in the art based on the present disclosure. The limitations in the claims are to be interpreted broadly based on the language employed in the claims and not limited to examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive. For example, in the present disclosure, the term “preferably” is non-exclusive and means “preferably, but not limited to”.