1. Field of the Invention
The present invention relates to a printing apparatus that performs processing for removing fingerprints left on a printing medium, and a method of controlling the same.
2. Description of the Related Art
Grease and moisture from the human body causes a reduction in resistivity in portions of a sheet that come into contact with a fixer, and there are cases where, for example, they cause a transfer failure when toner is transferred to the sheet, thus resulting in fingerprint marks being left on the printing result as shown by reference sign 1601 in
In Japanese Patent Laid-Open No. 2007-286108, the fingerprint removal mode is set using the operation unit of the image forming apparatus when printing sheets have been fed to the manual paper feed tray. For this reason, when the fingerprint removal mode is set, printing is performed in the fingerprint removal mode until all of the sheets set in the manual paper feed tray are gone. Since the fingerprint removal mode involves operations in which printed matter is passed through the fixer one time before being printed on and then discharged, the printing speed is slower than that in normal printing.
Fingerprints left on a sheet actually gradually disappear as time passes. Although it depends on the type and thickness of the printing sheet, fingerprints on ordinary copy sheets disappear in approximately 30 minutes. Accordingly, there are cases where fingerprint removal does not need to be performed for printing sheets for which a long time has passed since being stored in the paper feed tray. Performing fingerprint removal in such case results in an unnecessary increase in the printing time.
An aspect of the present invention is to eliminate the above-mentioned problems with the conventional technology. The present invention provides a printing apparatus that shortens the printing time when employing the fingerprint removal mode, and a method of controlling the same.
The present invention in its first aspect provides a printing apparatus comprising: a printing unit configured to transfer an image to a sheet conveyed from a sheet storage unit and fix the transferred image to the sheet using a fixing unit; and a control unit configured to, if the elapsed time since the sheet was stored in the sheet storage unit is less than or equal to a threshold value, perform control such that the sheet is heated by the fixing unit before the image is transferred to the sheet, and if the elapsed time since the sheet was stored in the sheet storage unit exceeds the threshold value, perform control such that processing for heating the sheet with the fixing unit before the image is transferred to the sheet is not performed.
The present invention enables shortening the printing time when employing the fingerprint removal mode.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
Preferred embodiments of the present invention will now be described hereinafter in detail, with reference to the accompanying drawings. It is to be understood that the following embodiments are not intended to limit the claims of the present invention, and that not all of the combinations of the aspects that are described according to the following embodiments are necessarily required with respect to the means to solve the problems according to the present invention. Note that like constituent elements will be denoted by like reference signs, and redundant descriptions thereof will not be given.
Embodiment 1
Configuration of Image Forming System
The client PCs 101 to 103 all have the same configuration. Although the following description is given for the client PC 101, it similarly applies to the client PCs 102 and 103 as well. As modules, the client PC 101 implements a print driver 108 and a status display unit 107 that displays the status of the image forming apparatus 104. Although the status display unit 107 is implemented so as to be included in the print driver 108 in the following description, it may be implemented separately from the print driver 108 as shown in
The status display unit 107 displays a status indicating the apparatus status of the image forming apparatus 104 on a screen of the client PC 101 so as to notify the user. Here, the status display unit 107 displays statuses of the image forming apparatus 104 such as “idling”, “printing”, and “toner shortage”, as well as printer error statuses such as “no paper” and “paper jam”. The status display unit 107 can acquire the status of a registered image forming apparatus 104 at any time by requesting the status from that image forming apparatus 104 at a constant time interval. Also, the status display unit 107 periodically updates the display of the status of the image forming apparatus 104 based on the results of the status request. The user can therefore determine whether or not a print job can be input based on the up-to-date display of the status of the image forming apparatus 104.
Block Configuration of Image Forming Apparatus
A printing apparatus is described as an example of the image forming apparatus in the present embodiment. The image forming apparatus 104 may be, for example, an apparatus that has functions other than printing, such as a multi-function device in which multiple functions such as copy and scanning are integrated. A printing apparatus that has at least a printing configuration and a configuration for receiving user operations is used as the image forming apparatus 104 of the present embodiment. The image forming apparatus 104 receives a print job input by the client PC 101, and executes printing based on the print job. As shown in
Control Unit 112
The control unit 112 includes a CPU, a ROM, a RAM, and an HDD. The control unit 112 starts an operating system (OS) with a boot program stored in the ROM, and executes various types of processing by executing application programs saved in the HDD on the OS. The control unit 112 controls various units, and performs print processing while cooperating with other units based on a print job saved in the image saving unit 111. Information regarding a sheet size, a sheet type, a paper feed tray (sheet storage unit), and a paper discharge tray is described in a print job, and the control unit 112 executes the print job based on such information. The control unit 112 also saves PDL code described in the print job to the image saving unit 111.
Job Interpretation Unit 109
A print job is described in a printer language called PDL code. Print jobs input from the client PC 101 via the network 100 are interpreted by the job interpretation unit 109 in the order of input. The job interpretation unit 109 interprets information such as a sheet size, a sheet type, a paper feed tray, and a paper discharge tray, and saves the interpreted information in the image saving unit 111 in association with the print job. A flag indicating whether the data to be output is character data or image data is also set in the print job. Although this will be described later, the job interpretation unit 109 reads this flag and selects the print mode in which print processing is to be executed.
Image Forming Unit 113
The image forming unit 113 generates image data based on the PDL code of an input print job. Processing for generating image data from PDL code is generally called rasterizing (or RIP). As described above, a flag indicating whether the data to be output is character data or image data is set in the print job. The image forming unit 113 performs edge filter processing on character data so that character edges have a good appearance. The image forming unit 113 performs smoothing filter processing on image data so as to obtain a smooth image compared to peripheral pixels.
Image Saving Unit 111
The image saving unit 111 is configured by a memory, an HDD, or the like, and temporarily saves rasterized image data generated by the image forming unit 113 until processing is performed by the fixing unit 114. The image saving unit 111 also saves interpretation results of the job interpretation unit 109 in association with rasterized image data in units of jobs. Also, the image saving unit 111 saves print jobs input from the client PC 101 as PDL code as well. The image saving unit 111 further saves a paper feed tray database 800 shown in
Operation Unit 110
Fixing Unit 114
In the present embodiment, sheets are supplied from a manual paper feed portion and three levels of POD decks included in a high capacity sheet feeding deck 513, via a conveyance path 509 to the right of the photosensitive drum. Note that the manual paper feed portion is mounted in place of the high capacity sheet feeding deck 513 when the high capacity sheet feeding deck 513 has been detached. Also, sheets are supplied from a built-in cassette via a conveyance path 510 below the photosensitive drum. A sheet with a toner image transferred thereon is conveyed to a pair of fixing rollers 505 by the driving of a conveyance belt. The pair of fixing rollers is configured as a pair made up of a heating roller and a pressing roller. The pair of fixing rollers 505 heats and presses the printing medium, thus fixing the toner image on to the sheet. After passing through the pair of fixing rollers 505, the sheet is discharged to a paper discharge accessory by a pair of paper discharge rollers 506. The paper discharge accessory is an apparatus that executes post-processing (also called “finishing”) such as sorting and stapling.
Here, in the case where the image forming apparatus 104 operates in a later-described fingerprint removal mode, fingerprints are removed by applying heat with the fixing unit 114 to a supplied sheet one time before printing (pre-print processing), and then the sheet subjected to fixing is turned back by a flapper 507 and guided to a paper re-feed conveyance path 508. On the other hand, in the case where double-sided printing in particular has been designated in a normal print mode, the sheet is guided by the flapper 507 to an inverting path 511. The sheet conveyed along the inverting path 511 is then guided by the flapper 512 to the paper re-feed conveyance path 508. The printing medium guided to the paper re-feed conveyance path 508 is then re-supplied between the photosensitive drum 503 and the transfer unit 504 at predetermined timing, and a toner image is transferred onto the underside of the sheet.
In this way, in the present embodiment, the conveyance path in the case of the fingerprint removal mode and the conveyance path in the case of the double-sided printing are switched by an instruction from the control unit 112.
Paper Discharge Unit 115
The paper discharge unit 115 discharges sheets subjected to fixing by the fixing unit 114 in the order set in the print job. The image forming apparatus 104 can apply various paper discharge accessories according to the finishing mode set in the print job. Also, the control unit 112 can reference various types of information on paper discharge accessories saved in the image forming apparatus 104, determine the paper discharge functions that can be performed, and display those finishing modes on the operation unit 110.
When a print job is input from the client PC 101, the job interpretation unit 109 references information on the various paper feed trays. The control unit 112 references the information on the various paper feed trays from the paper feed tray database 800 saved in the image saving unit 111. The control unit 112 can switch the fingerprint removal mode and the normal print mode according to the information on the various paper feed trays. This will be described in detail later.
Job Management Screen
In the case of performing job management, the user presses the jobs tab 405 in the bottom portion of the operation screen.
The current status of the image forming apparatus 104 is displayed as an item 401 in the top portion of the operation screen in
As previously described, the print driver 108 of the client PC 101 receives, from the image forming apparatus 104, printing errors and various types of information on paper feeding, paper discharge accessories, and the like. Information in the sheet type database 1100 (described later) in
Paper Feed Tray Setting
In the case where the user is to add or newly replenish sheets in a paper feed tray, the user selects a paper feed tray button 601 on the setting screen 600 by pressing it, and then presses an assign button 603. The paper feed tray button 601 and the accessories arranged in the image forming apparatus 104 are coordinated, and the control unit 112 opens the cassette of the paper feed accessory at the same position as the button pressed by the user. The user then adds or newly replenishes sheets to be used for printing in the open paper feed tray, and then closes the cassette. When the control unit 112 detects that the paper feed tray cassette was closed using a sensor or the like, the control unit 112 displays a sheet media setting screen on the operation unit 110.
If the user presses a paper feed tray button 601 and then presses an OK button 604, the control unit 112 opens the paper feed tray that corresponds to the paper feed tray button that was pressed (step S901). A sensor is disposed in each paper feed tray, and the control unit 112 can recognize that the paper feed trays have been opened or closed (one example of detection in replenishing). In order to store information indicating that the paper feed tray was opened, the control unit 112 sets a paper feed tray open item 806 in the paper feed tray database 800 to “Open”. When the paper feed tray is opened, that is to say, when sheet replenishing is performed, the control unit 112 detects the remaining sheet amount in the paper feed tray (step S902). For each paper feed tray other than the manual paper feed tray, the control unit 112 can detect the remaining sheet amount as a percentage based on the percentage of 100% for the full state (one example of remaining amount detection). In particular, for a paper feed tray in which sheets are loaded with the printing surface face-down, the control unit 112 can, based on the remaining sheet amounts when the user opened the paper feed tray and when the user closed the paper feed tray, approximately specify how many sheets down from the top a sheet likely to have fingerprints left thereon is in the current sheet bundle.
All of the items in the paper feed tray database 800 stored in the image saving unit 111 are updated each time the information on the paper feed trays changes, such as when printing is performed and when sheets are replaced in the paper feed trays. Accordingly, up-to-date information regarding the paper feed trays is always saved in the paper feed tray database 800. First, based on the items 802 in the paper feed tray database 800, the control unit 112 acquires the remaining sheet amount for the paper feed tray to which the user desires to input sheets. Then, when the user closes the paper feed tray, the control unit 112 again detects the remaining sheet amount, and determines an increase/decrease in the remaining sheet amount (step S903). Here, if it is determined that the remaining sheet amount increased, the control unit 112 saves the added sheet amount in an item 803 in the paper feed tray database 800. The control unit 112 also saves the time when the user closed the paper feed tray in an item 804 in the paper feed tray database 800 (step S904). The control unit 112 furthermore measures the elapsed time from that time, and saves the measured elapsed time in the item 804 as well. When the user presses the OK button 604 in the paper feed tray setting screen 600 or the trays tab screen, the processing of
Paper Feed Tray Selection, Mode Check
If the user presses the media information button 402 in the job list 403, the control unit 112 displays the paper feed tray setting screen 600. When the media information button 402 is pressed by the user, information on the sheets in the paper feed trays connected to the image forming apparatus 104 is displayed on the paper feed tray setting screen 600 along with images of the paper feed trays, based on the paper feed tray database 800. If the user selects a paper feed tray button 601 on the paper feed tray setting screen 600 and then presses the OK button 604, the control unit 112 associates that paper feed tray with the print job that is the current processing target. At this time, the control unit 112 can also select multiple paper feed trays and assign them to the print job.
The control unit 112 determines whether or not the fingerprint removal mode item 801 in the paper feed tray database 800 saved in the image saving unit 111 is “ON” for the paper feed tray to be used in the print job (step S1001). If it is determined that the fingerprint removal mode item in the paper feed tray database 800 is “ON”, the control unit 112 acquires the sheet type set in the paper feed tray selected by the user from among the sheet type items in the paper feed tray database 800.
Next, the control unit 112 searches for media information set for the paper feed tray in a table indicated as the sheet type database 1100 in
Based on the paper feed tray database 800, the control unit 112 compares the fingerprint removal time 1102 that corresponds to the sheet media set in the print job with the elapsed time since sheets were replenished, which is saved as the item 804 in the paper feed tray database 800 (step S1004). Here, if a certain time has not elapsed, that is to say, if the elapsed time is less than or equal to the threshold value, the control unit 112 selects the fingerprint removal mode as the print mode (step S1005). On the other hand, if a certain time has elapsed, it is determined that the fingerprints have disappeared, and the control unit 112 selects the normal print mode as the print mode (step S1006).
In the present embodiment, if a sheet shortage occurs during printing, and furthermore there is a paper feed tray having the same type of sheets as the type of sheets being used in printing, the control unit 112 switches to the paper feed tray having the same sheets set therein. In this case as well, the control unit 112 selects the print mode based on the flowchart in
Printing Operations in Fingerprint Removal Mode
As was described with reference to
If the user touches a sheet bundle, fingerprints will be left on the upper surface of the sheet at the top of the sheet bundle and on the lower surface of the sheet at the bottom of the bundle. In the case of the conveyance path from the manual paper feed tray (first sheet storage unit) connected so as to supply sheets to the conveyance path 509 (“manual model”), sheets are not vertically inverted during conveyance in the image forming apparatus 104, and therefore the upper surface of the sheet at the top of the sheet bundle with fingerprints thereon comes into contact with the photosensitive drum 503 as the printing surface. Accordingly, if the selected paper feed tray is “manual model”, printing is performed in the fingerprint removal mode when printing on the first printing medium sheet. Printing is then performed in the normal print mode from the second sheet onward.
On the other hand, in the case of the conveyance path from the built-in cassette (second sheet storage unit) connected so as to feed sheets to the conveyance path 510 (“inversion cassette”), the sheet is vertically inverted during conveyance before coming into contact with the photosensitive drum 503. Accordingly, printing is performed in the normal print mode when printing on the first printing medium sheet. Also, since the lower surface of the sheet at the bottom of the added sheet bundle is inverted, the lower surface with fingerprints thereon comes into contact with the photosensitive drum 503 as the printing surface. Accordingly, the control unit 112 calculates, as an approximate calculation, the number of printed sheets until the surface with fingerprints thereon will come into contact with the photosensitive drum, based on the added sheet amount indicated by the item 803 in the paper feed tray database 800. This can be calculated based on, for example, the number of pages that can be printed in the case where the paper feed tray is full of sheets, and the current remaining sheet amount (%). In the vicinity of the surface with fingerprints thereon (e.g., at the 5th to 10th page from that surface), the control unit 112 performs printing in the fingerprint removal mode. In this way, the image forming apparatus 104 switches the print mode according to the paper feed tray.
Embodiment 2
In the present embodiment, the job interpretation unit 109 interprets the PDL code of a print job input from the client PC 101, and determines based on the interpretation result whether the print output information is character information or image information (one example of job determination). The result of this determination is used when the image forming unit 113 executes image forming processing. For example, if it is determined that the print output information is character information, filter processing is performed such that the character edges have a good appearance (edge processing). Also, if it is determined that the print output information is image information, filter processing is performed such that the image is smoother compared to peripheral pixels (smoothing processing).
Step S1301 in
Embodiment 3
In the present embodiment, the image saving unit 111 manages sheet types 1101 for the sheet media and the fingerprint removal times 1102 in the sheet type database 1100. Sheet types such as “normal paper” and “recycled paper” are set as the sheet types 1101 associated in the sheet type database 1100.
In the present embodiment, the image forming apparatus 104 can switch the print mode between the fingerprint removal mode and the normal print mode using the initial setting for each sheet type when performing printing. For example, a use mode is possible in which the fingerprint removal mode is not used in the case of performing printing with paper for which pre-printing is to be performed, such as recycled paper. In step S1501, the control unit 112 detects the sheet type of the printing medium set in the paper feed tray, and then moves to step S1003 in order to switch the print mode to the fingerprint removal mode depending on the sheet type.
Other Embodiments
Aspects of the present invention can also be realized by a computer of a system or apparatus (or devices such as a CPU or MPU) that reads out and executes a program recorded on a memory device to perform the functions of the above-described embodiments, and by a method, the steps of which are performed by a computer of a system or apparatus by, for example, reading out and executing a program recorded on a memory device to perform the functions of the above-described embodiments. For this purpose, the program is provided to the computer for example via a network or from a recording medium of various types serving as the memory device (e.g., computer-readable medium).
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application Nos. 2012-172301, filed Aug. 2, 2012, and 2012-172300, filed Aug. 2, 2012, which are hereby incorporated by reference herein in their entirety.
Number | Date | Country | Kind |
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2012-172300 | Aug 2012 | JP | national |
2012-172301 | Aug 2012 | JP | national |
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Number | Date | Country | |
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20140037301 A1 | Feb 2014 | US |