JP2005173144A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus with which the saving of consumables, such as toners, and energy is insured and the possibility of the occurrence of a misprint is eliminated. <P>SOLUTION: The image forming apparatus is equipped with an image forming means for forming a toner image to print paper and a fixing means for thermally fixing the toner image formed by the image forming means to the print paper and is provided with an automatic print mode setting means which has a saving print mode for making the amount of the toner consumption in the image forming means lower than usual or executing an image formation operation by making the fixing temperature in the fixing means lower than usual and automatically sets the saving print mode or the ordinary print mode based on the kind of the print form fed to the apparatus. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention includes an image forming unit that forms a toner image on a print sheet, and a fixing unit that thermally fixes the toner image formed by the image forming unit to the print sheet. The present invention relates to an image forming apparatus provided with a saving print mode in which an image forming operation is executed by reducing the fixing temperature by the fixing unit or lowering the fixing temperature.

In image forming apparatuses that employ electrophotography such as laser printers, digital copiers, and facsimile machines that form images by attaching toner to paper according to image data, masking patterns in dot units are superimposed on the image data. For example, a method of reducing the number of pixels to be written to reduce toner consumption has been proposed. For example, Patent Document 1 describes a method of adjusting the density of a digital image to reduce the number of dots to be printed by adding a generated mask pattern to image data before printing, and Patent Document 2 describes toner consumption. An electrophotographic apparatus that has a toner consumption saving mode that saves toner and that saves toner consumption regardless of the remaining amount of toner in the toner consumption saving mode is disclosed. A laser beam exposure type electrophotographic apparatus that reduces the image density by reducing the development width per dot of the laser beam when it is detected that the following is satisfied is disclosed. A toner saving mode that suppresses toner consumption by superimposing the image and a high-quality image output mode that performs normal high-quality image formation. Control method according to the high-quality image output mode by releasing the toner saving mode is described in case of forming an image be constant reduced beyond a predetermined magnification.
JP-A-7-111588 JP-A-8-123257 Japanese Patent Laid-Open No. 1-133075 JP 2000-155504 A

  However, the above-described printing in the conventional saving mode causes a certain degree of image quality degradation and is not used for printing of important contents. Even important contents are used as official documents. Since it is not printed for the purpose of distribution to the outside, there is not much use of high-quality paper as print paper, and it is sufficient to use recycled paper or the back side of printed paper. However, it is complicated and difficult for the user to intentionally select such a print sheet and set the saving mode. For example, there are cases where printing is performed on high-quality paper by mistake while the saving mode is set, or printing on recycled paper is mistakenly performed while setting the normal mode.

  SUMMARY OF THE INVENTION In view of the above-described conventional drawbacks, the present invention is to provide an image forming apparatus that can reliably save consumables such as toner and energy and that does not cause erroneous printing.

  In order to achieve the above object, a first characteristic configuration of an image forming apparatus according to the present invention is an image forming unit that forms a toner image on a print sheet, as described in claim 1 of the document of claims. A fixing unit that heat-fixes the toner image formed by the image forming unit on a print sheet, and reduces a toner consumption amount in the image forming unit from a normal level or a fixing temperature by the fixing unit from a normal level; An image forming apparatus having a saving print mode for executing an image forming operation, and provided with a print mode automatic setting means for automatically setting the saving print mode or the normal print mode based on the type of printing paper supplied. In the point.

  According to the above configuration, when the supplied print paper uses recycled paper suitable for the save print mode or the reverse side of the printed paper, the save print mode is selected. When the supplied print paper is fine paper, the normal print mode is set. Since the automatic setting is performed, it is not necessary to make a troublesome operation and determination based on matching between the saving print mode and the paper, and it is possible to reliably prevent erroneous printing and to perform saving printing reliably.

  In the above-described configuration, the print mode automatic setting unit determines the type of print paper when a specific paper feed stage is selected, and automatically sets the normal print mode to the saving print mode, or starts from the saving print mode. It is preferable to automatically set the normal print mode. For example, a selection can be made by associating a plurality of paper feed stages with a saving print mode such as a paper feed stage for recycled paper or a paper feed stage for high-quality paper in advance. Either the saving print mode or the normal print mode can be automatically set depending on the paper feed stage.

  Further, the print mode automatic setting means determines the type of print paper by the type determination means provided in the paper feed path, and automatically sets the normal print mode to the saving print mode, or from the saving print mode to the normal print mode. Preferably, the mode is automatically set by detecting the type of print paper fed from an arbitrary paper feed stage by the type determination means provided on the paper feed path. Also free from complicated operations. For example, when an image sensor is provided in the paper feed path and an image is confirmed on the surface opposite to the print target surface, it is determined that the print job uses the back side of the used paper and the saving print mode is set. It can be set automatically.

  As described above, according to the present invention, it is possible to provide an image forming apparatus that can reliably save consumables such as toner and energy, and that does not cause the possibility of erroneous printing.

  In the following, an embodiment of an image forming apparatus according to the present invention will be described by taking a multifunction digital copying machine as an example. However, the present invention is applicable to an image forming apparatus employing an electrophotographic system such as a printer apparatus or a facsimile apparatus. As shown in FIG. 1, the digital copying machine 1 has a main body in which an exposure mechanism 2 as image reading means for reading document image information, a printing mechanism 3 as image forming means, and a recording paper transport mechanism 4 including fixing means are arranged. A contact glass 5 for placing a document to be copied (a copy document) and an operation display unit 6 are provided on the upper surface of the paper, and an automatic document feeder 7 is disposed on the contact glass 5 and is fed to one side of the main body. A paper cassette 8 is arranged.

  The exposure mechanism 2 includes a first slider 2A including an exposure lamp 21 for exposing and scanning a document placed on the contact glass 5, and a first mirror 22 for reflecting reflected light from the document, and a first mirror. A second slider 2B having second and third mirrors 23 and 24 for guiding the light reflected by the lens 22 to the lens 25, and a CCD for converting the optical information obtained by the condenser lens 25 into an electrical signal. And the like, a control unit 27 to which image information obtained by the solid-state image sensor 26 is input, and a laser unit 28 that converts image data from the control unit 27 into an optical signal.

  The print mechanism 3 includes a photosensitive drum 31 that is driven to rotate in the direction of an arrow by a main drive motor (not shown). The photosensitive drum 31 has a photosensitive drum 31 around the photosensitive drum 31 in the order of the rotation direction. A charger 32 for charging the layer, a developing device 33 for visualizing the electrostatic latent image formed on the photosensitive layer as a toner visible image, and a transfer device for transferring the toner visible image formed on the photosensitive layer to recording paper Discharger 34, separation discharger 35 for separating the recording paper from the photosensitive drum 31, cleaning device 36 for removing toner remaining on the photosensitive drum 31 after transfer, and charge on the surface of the photosensitive drum 31 Each of the static eliminators 37 is disposed to irradiate the photosensitive layer uniformly charged by the charger 32 with the laser beam output from the laser unit 28, thereby forming an electrostatic latent image.

  The recording paper transport mechanism 4 is fed by paper feed rollers 41A, 41B, and 41C and paper feed rollers 41A, 41B, and 41C that feed the papers of the paper feed cassettes 8A, 8B, and 8C provided in three stages on the top and bottom. The registration roller 42 for conveying the received paper to the photosensitive drum 31 at a predetermined timing and the recording paper on which the toner visible image formed on the photosensitive drum 31 is transferred and peeled off from the photosensitive drum 31 are fixed to the fixing roller. A conveying belt 43 that conveys the toner to 44 is provided. The transfer paper subjected to the fixing process by the fixing roller 44 is discharged onto a discharge tray through a discharge mechanism (not shown).

  As shown in FIG. 2, the control unit 27 stores various operation programs of the digital copying machine 1, that is, control programs such as the exposure mechanism 2, the print mechanism 3, the recording paper transport mechanism 4, and the operation display unit 6 described above. ROM 103, CPU 101 for controlling the required operation of digital copying machine 1 based on the program stored in ROM 103, data necessary for processing by CPU 101, and image information read by the image reading means as a job The RAM 104 as an image storage unit that stores data in units, and the image information obtained by the solid-state imaging device 26 as the image processing unit that reads out the image information stored in the image storage unit and executes the predetermined process. And an image processing circuit 102 for generating output image information to the laser unit 28. That.

  Image data obtained by the image processing circuit 102 is temporarily stored in the RAM 104, read out, and sent to the laser unit 28. The RAM 104 stores image information in a predetermined job unit for a series of continuous document information, and the CPU 101 stores each element of a process processing unit including the exposure mechanism 2, the print mechanism 3, and the recording paper transport mechanism 4. Drive information is controlled at a predetermined timing, and the image information sent to the laser unit 28 is printed on a recording sheet and output.

  The above-described digital copying machine 1 is provided with a saving print mode, and either the saving print mode or the normal print mode can be set by operating a mode switching key (not shown) provided on the operation display unit. A display unit configured and capable of identifying the set print mode is provided. The saving print mode will be described in detail. A toner saving mode in which the toner consumption in the image forming unit is reduced than usual, and a power saving mode in which the fixing temperature by the fixing unit is lowered than usual. In addition, the toner saving mode prints image data obtained by superimposing a predetermined masking pattern on the image data developed in the form of a bitmap in the RAM 104, although the fixing performance is reduced but economical printing is obtained. A mode that suppresses toner consumption by outputting.

  Each of the cassettes 8A, 8B, and 8C has a combination of a plurality of magnets and a reed switch, and a type determination unit 9 that can determine the size of the stored paper and whether the paper is used in the saving print mode ( 9A, 9B, 9C) are provided, the corresponding cassette detected by the type determining unit is automatically selected when the saving print mode is selected, and the response detected by the type determining unit 9 is selected when the normal print mode is selected. The control program is configured so that the cassette to be automatically selected. As a result, in the normal print mode, a cassette containing high-quality paper is automatically selected, and in the saving print mode, a cassette containing recycled paper or recycled paper using the used back side is automatically selected. ing.

  When performing print processing in the saving print mode set by the mode switching key described above, the user switches to a cassette that does not support the saving print mode by operating the cassette selection key or the paper size key on the operation display unit. May occur. Similarly, when performing the printing process in the normal print mode, the cassette may be switched to a cassette that does not support the normal print mode. Therefore, print mode automatic setting means 101A for automatically setting the saving print mode or the normal print mode based on the type of print paper supplied is provided. The print mode automatic setting unit 101A determines the type of print paper by detecting whether or not the type determination unit 9 is a cassette corresponding to the print mode when the cassette is switched, and the normal print mode is selected. When the printer is switched to the cassette for the saving print mode, the saving printing mode is automatically set. When the saving printing mode is selected, the cassette is automatically set to the normal printing mode when the cassette is switched to the normal printing mode.

  As described above, as shown in FIG. 1, paper feeding is performed in the case where a cassette is not associated with the print mode or a sheet different from the associated paper is accommodated. Type determination means 9D made of a solid-state image sensor is provided immediately before the registration roller 42 provided in the path. The type determination unit 9D can determine whether or not to print on the back side of the used paper by, for example, imaging the back side of the paper stopped by the registration roller 42 and detecting the presence or absence of some printing information. When the back side of the used paper is detected in the normal print mode, the print mode automatic setting unit 101A automatically sets the normal print mode to the saving print mode, and uses the high-quality paper (print information by the type determination unit 9D) in the saving print mode. Is detected, it is determined that the paper is a high-quality paper), and the saving print mode is automatically set to the normal print mode.

  Such an automatic setting operation is realized by a control program stored in the ROM 103 and a CPU that executes the control program, and the procedure is shown in the flowcharts of FIGS. FIG. 3A shows the case where the normal print mode is selected and the print key is turned on, and FIG. 3B shows the case where the cassette is switched after the normal print mode is selected. FIG. 4A shows a case where the saving print mode is automatically switched, and FIG. 4A shows a case where the cassette is inserted after the saving print mode is selected. This shows a case where, when switching is performed, the mode is automatically switched from the saving print mode to the normal print mode.

  Here, the type determining means 9 is not limited to one constituted by a magnet and a reed switch provided in the cassette, but based on an operation input for associating each cassette so as to correspond to each print mode from the operation display unit 6. The association information may be stored in the RAM 104.

  In the above-described embodiment, the saving print mode includes the toner saving mode in which the toner consumption in the image forming unit is reduced by using a masking pattern than normal, and the power saving mode in which the fixing temperature by the fixing unit is reduced from normal. In addition, when the document is a photographic image, the output resolution is set to be coarse, the dot density is printed when characters are printed in a dot pattern, and a plurality of originals are combined. Any saving print mode that combines the aggregate print mode or the reduced print mode for consolidating on a sheet of paper can be used. It is also possible to configure which of these is adopted as the saving print mode so that the initial setting can be made via the operation display unit 6. For example, the operation display unit 6 is provided with a setting mode for setting and inputting the contents of the saving print mode so that the user can individually select whether or not to adopt based on a list of settable modes displayed in the setting mode. Is. At this time, a corresponding cassette may be selected.

Schematic explanatory diagram of the image forming apparatus FIG. 3 is a control block diagram of the image forming apparatus. flowchart flowchart

Explanation of symbols

3: Image forming means 44: Fixing means (fixing roller)
101A: Print mode automatic setting means 9 (9A, 9B, 9C, 9D): Type determination means

Claims (3)

An image forming unit that forms a toner image on a print sheet, and a fixing unit that thermally fixes the toner image formed by the image forming unit to the print sheet, and the toner consumption in the image forming unit is reduced more than usual, or An image forming apparatus having a saving print mode for performing an image forming operation by lowering a fixing temperature by the fixing unit than usual;
An image forming apparatus provided with automatic print mode setting means for automatically setting the saving print mode or the normal print mode based on the type of print paper supplied. The print mode automatic setting means determines the type of print paper when a specific paper feed stage is selected, automatically sets the normal print mode to the saving print mode, or automatically changes from the saving print mode to the normal print mode. The image forming apparatus according to claim 1, wherein the image forming apparatus is set. The print mode automatic setting unit determines the type of print paper by a type determination unit provided in the paper feed path, and automatically sets the normal print mode to the saving print mode, or automatically sets the save print mode to the normal print mode. The image forming apparatus according to claim 1.

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