JP2005164730A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of realizing operation to improve fixing performance to cardboard and rough paper by carrying paper through the straight carrying path of an ordinary image forming apparatus without using an image forming apparatus capable of automatic double-sided printing. <P>SOLUTION: The image forming apparatus is provided with one or more paper feeding devices for housing and feeding paper, an image forming part capable of forming the image on the paper, a fixing part for fixing the image by heating and pressuring the paper on which the image is formed, and an operation part for performing input and display related to the operation. In the case of feeding the paper from the specified paper feeding device (S2), the paper is made to pass in a state where the image is not formed in the image forming part (S3) and ejected after it is heated and pressured by the fixing part (S12 and S14), and then a message to urge to place the ejected paper on the prescribed paper feeding device is displayed on the operation part (S18). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus using thick recording paper.

  In an electrophotographic image forming apparatus, a charged photosensitive member is exposed to form an electrostatic latent image, and the electrostatic latent image is developed with toner to form a visible image. Then, after transferring the visible image to a sheet, a method of fixing the image by heating and pressurizing the sheet is generally performed.

However, there are various types of paper as recording paper, and various ideas have been devised so that a visible image of toner is fixed on these papers. For example, in order to cope with various types of paper, there are methods such as control of the fixing temperature, pressurization at the time of fixing, and control of the conveyance speed of the paper at the time of fixing. However, in any of these methods, the fixing property tends to be poor on thick paper with a large amount of weight, paper on a bag such as an envelope, or rough paper with a rough surface. Even in an image forming apparatus with improved fixing performance, generally, the upper limit is thick paper or an envelope having a weight of about 200 g / m ² .

  Patent Document 1 proposes to use an image forming apparatus capable of automatic double-sided printing in order to improve fixability with thick paper or rough paper in the image forming apparatus. FIG. 5 is a front cross-sectional view of an image forming apparatus disclosed in Patent Document 1 and capable of automatic double-sided printing. The paper is stored in the paper feed cassette 102 of the image forming apparatus 101. In this case, the paper is a thick paper with poor fixability. When such thick paper is fed from the paper feed cassette 102 by the paper feed roller 103, the direction is changed by the feed roller 104 and conveyed by the registration roller 105. Then, it passes through the gap between the photosensitive drum 107 and the transfer roller 108. In this case, unlike the normal image forming process, image formation is not performed.

  Thereafter, the sheet passes through the fixing unit 110 and the post-fixing roller pair 111 heated by the heater 110a. At this time, since the branching device 114 forms a downward conveying path in the drawing, the sheet is conveyed to the reversing unit 115 via the reversing roller 116 (the above conveying path is indicated by a broken line and a black arrow). . Since the reverse roller 116 rotates in the reverse direction when the paper is stored in the reversing unit 115 and the rear end is sandwiched between the reversing rollers 116, the paper passes through the transport rollers 117, 118, and 119, and the feed roller 104. Is redirected by.

  When the sheet reaches the registration roller 105 again, image formation is performed at this time, and therefore, the sheet is fed to the gap between the photosensitive drum 107 and the transfer roller 108 after the timing is adjusted. The toner image on the photosensitive drum 107 is transferred to a sheet by the transfer voltage applied to the transfer roller 108 and is fixed by the fixing unit 110. Thereafter, the branching device 114 is switched so as to guide the paper in the left direction, so that the paper that has passed through the post-fixing roller pair 111 is discharged onto the discharge tray 120 by the discharge roller pair 112 (the above transport path is (It is indicated by a dashed line and a white arrow). Note that components not related to the description of the developing device, the scanner, and the like are omitted.

As apparent from the above description and FIG. 5, in order to improve the fixing property, the automatic duplex function of the image forming apparatus 101 is used, and the sheet is fixed without forming an image in the first process of automatic duplex. Heat at 110. Then, in the second process of automatic double-sided printing, an image is formed and transferred to a sheet, which is fixed by the fixing unit 110. That is, moisture contained in the paper is vaporized in the first process. Therefore, in the second process, the heat of the fixing unit 110 is given to the toner image and the paper without being taken away by the vaporization of moisture, so that the fixing property is improved.
JP 2000-132007 A

  The method proposed in Patent Document 1 is certainly effective in improving the fixability when using paper or rough paper with a large weight. However, for that purpose, it is a necessary condition to use an image forming apparatus capable of automatic duplex printing. Also, the automatic duplex mechanism often turns the paper to an acute angle. For example, the feeding roller 104 in the conveyance path indicated by the one-dot chain line shown in FIG. Here, curl and wrinkles occur on the paper because the cardboard and envelope are turned 180 degrees to an acute angle. In the worst case, there is an extremely high possibility that the paper will be jammed in the subsequent conveyance path due to the curl and wrinkle. In particular, in the case of bag-like paper, wrinkles deteriorate when curling occurs.

  The present invention has been made in view of such a situation, and without using an image forming apparatus capable of automatic double-sided printing, enables a sheet to be conveyed on a straight conveyance path of a normal image forming apparatus, An object of the present invention is to provide an image forming apparatus capable of performing an operation for improving the fixing performance for thick paper and rough paper.

  In order to achieve the above object, an image forming apparatus according to the present invention includes one or more sheet feeding apparatuses that store and feed a sheet, an image forming unit capable of forming an image on the sheet, and a sheet on which an image is formed. When a sheet is fed from a specific sheet feeding device, the image forming section includes an image forming section that has a fixing section that heats and pressurizes the image to fix the image and an operation section that performs input and display related to the operation. The sheet is passed without being formed, and the sheet is heated and pressurized by the fixing unit to be discharged, and a message prompting the user to place the discharged sheet on a predetermined sheet feeding device is displayed on the operation unit.

  The image forming apparatus according to the present invention includes a storage unit that stores setting data, and a specific paper feeding device to which paper is fed and a predetermined paper feeding device on which the discharged paper is placed are stored in advance. Registered in the storage unit.

  In the image forming apparatus according to the present invention, when the paper is heated in the fixing unit, the temperature of the fixing unit is controlled to be higher than the temperature in fixing the image.

  In addition, in the image forming apparatus according to the present invention, when an input is performed using a predetermined key of the operation unit after the message is displayed, a sheet placed on a predetermined sheet feeding device is fed, and an image is displayed on the sheet. Formation takes place.

  Furthermore, the image forming apparatus according to the present invention causes the notification device to ring together with the display of the message.

  According to the image forming apparatus of the present invention, an image can be printed on cardboard, envelope, and rough paper having poor fixability without using an image forming apparatus having an automatic duplex printing structure that is expensive, complicated, and unsuitable for transporting cardboard and envelopes. It can be formed and sufficiently fixed.

  In addition, according to the image forming apparatus of the present invention, a paper feeding device that stores special paper such as thick paper, envelope, and rough paper that has poor fixability and a paper feeding device that places heated paper are set in advance. It can be registered in the storage unit. Therefore, those settings can be easily changed, and it is possible to set the sheet feeding device in which a straight conveyance path is formed.

  Furthermore, according to the image forming apparatus of the present invention, when the special paper is heated, the temperature is set higher than the normal printing temperature, so that the water contained in the paper can be rapidly evaporated and overheated. Become.

  In addition, according to the image forming apparatus of the present invention, the sheet heated by the message is placed on the sheet feeding device, and when a predetermined key input is performed, printing is automatically performed thereafter. Even if the image forming apparatus does not have the function, the user does not need to perform a complicated operation.

  Further, since the notification device is sounded together with a message prompting the user to place the discharged paper, it is possible to call attention even if the user is located away from the image forming apparatus.

  Hereinafter, the details of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic front view showing a schematic configuration and structure of an image forming apparatus to which the present invention is applied. The image forming apparatus 1 serves as a recording medium, an image reading unit 2 that reads a placed document and converts it into image data, an operation unit 7 including a display unit 4, an operation input unit 5, and a notification device 6. A paper feeding unit 10 that houses the paper P and feeds it one by one, a feed roller pair 11 that continues to feed the fed paper P, and a registration roller that temporarily stops the paper P for timing adjustment with the image 12, an image forming unit 13 for forming an image, a transfer roller 15 for transferring the image to the paper P, a fixing unit 16 for fixing the image to the paper, a discharge tray 17 for discharging the paper, and all of these A control unit 19 that performs control is schematically configured.

  The sheet feeding unit 10 of the image forming apparatus 1 has one or a plurality of sheets P placed thereon, a so-called manual sheet feeding tray 21 that can perform manual sheet feeding, and a first sheet that can store a plurality of sheets P. The sheet feeding unit 22, the second sheet feeding unit 23, and the third sheet feeding unit 24 are configured to feed the sheet from the sheet feeding tray and the sheet feeding unit, respectively, by the sheet feeding rollers 21 a, 22 a, 23 a, 24 a. Is done by.

  The image forming unit 13 exposes the photosensitive member 30 that rotates in the direction of the arrow in the figure, a charging device 31 that charges the surface thereof, and the photosensitive member 30 that is charged according to the image data read by the image reading unit 2. An exposure device 32 (in this example, an LED head) that forms an electrostatic latent image, a developing device 33 that develops the electrostatic latent image into a visible image of toner, and the residual toner after transfer to the surface of the photoreceptor 30 And a cleaning device 34 for removing from the cleaning device 34.

  The fixing unit 16 is disposed concentrically with the heat roller 16a coated with a release material such as Teflon (R), a pressure roller 16b for pressing the paper P passing through the heat roller 16a, and the heat roller 16a. The heater 16c is overheated from the inner surface, and the temperature sensor 16d detects the temperature of the fixing unit 16.

  Next, a configuration relating to control of the image forming apparatus 1 will be described with reference to FIG. FIG. 2 is a block diagram for explaining the control of the image forming apparatus 1. Components having the same names and functions as those shown in FIG. 1 are denoted by the same reference numerals, and description thereof is simplified or omitted. The image reading unit 2, the operation unit 7, the paper feeding unit 10, the image forming unit 13, the fixing unit 16, and a driving unit serving as a driving source for the image forming apparatus 1 are connected to a control bus connected to the control unit 19. 40, a storage unit 41 in which various control parameters and setting data are stored, a printer controller 42 that performs image forming processing based on print data input from an external information processing apparatus (not shown), and transmission / reception with the outside Are connected to the communication control unit 43 that performs the communication control of the above, and are respectively controlled by the control unit 19.

  In the image forming apparatus 1 having such a configuration and control structure, cardboard, envelopes, or rough paper whose fixing properties are reduced by normal temperature control are used to suppress curling and wrinkles as much as possible, and there is a risk of paper jams. An embodiment in which image formation can be performed with reduced performance will be described. As described with respect to the prior art, in order to improve the fixability of a sheet having poor fixability without making a significant change to the image forming apparatus 1, the heat of the heating source is deprived in advance as the heat of vaporization during fixing. It is important to suppress moisture, that is, to keep the moisture content of the paper low. Furthermore, the smaller the amount of heat required to heat the sheet to the fixing temperature, the more effectively the heat source of the fixing unit 16 is used. Therefore, the initial temperature of the sheet during fixing may be increased. is important. In addition, since paper having a rough surface such as rough paper has poor adhesion of melted toner, it is important to increase the smoothness of the surface in advance.

  When thick paper or rough paper is used, in order to satisfy all of the above conditions, an image forming apparatus having a straight paper conveyance path as much as possible is used, and the paper is preliminarily formed by the fixing unit 16 without forming an image. It is necessary to devise a way to guide the user to re-feed and form an image before heating and the temperature of the paper drops to ambient temperature. Such an operation of the image forming apparatus will be described with reference to FIGS. FIG. 3 is a flowchart for explaining the operation of the image forming apparatus 1 according to the present invention. FIG. 4 is an example of an operation explanation display displayed on the display unit 4 (FIG. 1) when a pre-registered paper feeding unit is selected.

  First, when copying or printing is performed in the image forming apparatus 1, in step S1 (hereinafter, “step” is omitted), the user manually selects a sheet to be used. In this case, since the types of paper stored in the manual paper feed tray 21, the first paper feed unit 22, the second paper feed unit 23, and the third paper feed unit 24 are determined in advance, the paper is selected. This is the same as selecting one of these paper feed units. When the image forming apparatus 1 is in the automatic paper selection mode, the paper is automatically selected according to the document size. In either case of manual paper selection or automatic paper selection, the image forming apparatus 1 can specify the selected paper feed unit.

  In S <b> 2, it is determined whether or not the selected and specified paper feeding unit is a paper feeding unit that stores special paper with inferior fixability, such as thick paper, envelope, and rough paper, registered in the storage unit 41. . If they are different, the process branches to S26 and a normal printing operation is performed. In the case of a paper feed unit that stores special paper, the process proceeds to S3, and control is performed to prevent image formation in the image forming unit 13, and at the same time, the temperature of the fixing unit 16 heats the paper P in S5. The heater 16c is controlled to increase the temperature so that the temperature of the contained water is sufficiently vaporized. The normal operating temperature for fixing the image on the paper P is, for example, usually in the range of 150 ° C. to 170 ° C., but since the moisture contained in the paper P is rapidly evaporated, the temperature is close to the upper limit temperature allowed for the fixing unit 16. Whether or not the temperature has increased to a predetermined temperature, for example, 200 ° C., is determined in S7.

  When the predetermined temperature is reached, the drive unit 40 is activated in S9. In step S10, paper is fed from the specified paper feeding unit. An image is not formed on the paper P and passes through the image forming unit 13, and in S <b> 16, when it passes through the fixing unit 16, it is rapidly heated at a predetermined temperature to evaporate water. In S <b> 14, the heated paper P is discharged onto the discharge tray 17. At the same time, in S15, the temperature control of the fixing unit 16 is returned from the predetermined temperature control to the operating temperature control during printing. Also, in S16, the notification device 6 is turned on and rings to prompt the user to perform the next operation.

  Further, in S18, the description of the operation illustrated in FIG. 4 is displayed on the display unit 4 of the image forming apparatus 1. When the image forming apparatus 1 is a printer, an operation description as shown in FIG. 4 is transmitted to the information processing apparatus that is the transmission source of the print data and displayed together with the display on the display unit 4. In accordance with this operation description, the user places the paper P discharged in S14 on the manual paper feed tray 21 and then a predetermined key (in this example, the Enter key on the operation input unit 5 of the image forming apparatus 1). push. When the input of the predetermined key is detected in S19, the display of the operation explanation is turned off in S20, and the notification device is also turned off in S22. At the same time, in S23, it is checked whether the temperature of the fixing unit 16 is lowered to the normal operating temperature (printing temperature). In the case of the operating temperature, the paper P placed on the manual paper feed tray 21 is fed in S25, and predetermined printing is performed in S26.

  If the input waiting for the predetermined key continues in S19, the process waits for the input because the process goes through S30. If the input waiting time is longer than the predetermined time, it is determined as a timeout in S30. This is because if the heated paper P is left in the discharge tray 17 for a long time, the paper P absorbs moisture when the surrounding humidity is high, and the temperature of the paper P itself also decreases. This is because it cannot be expected. Furthermore, if the user forgets to place the discharged paper P on the manual paper feed tray 21, copying or printing processing by another user cannot be performed. Therefore, if it is determined in S30 that the predetermined time has elapsed, the process proceeds to S31, the display of the operation explanation is deleted, the notification device is turned off in S32, and this process is terminated.

  In the above description, the example in which the heated paper P is placed on the manual paper feed tray 21 has been described. However, as is apparent from the structure of the image forming apparatus 1 in FIG. This is because when the tray 21 is used, a straight conveyance path in which special paper is difficult to curl is formed. Therefore, it is preferable to determine a paper feed tray or a paper feed unit on which heated paper is placed for refeeding according to the structure of the actual image forming apparatus to which the present invention is applied. Needless to say, the present invention is not limited to the differential feed tray.

  Although the embodiments of the invention have been described based on the specific configuration of the image forming apparatus 1, it is needless to say that the present invention is not limited to the illustrated configuration. Further, the copying machine has been described as an example of the image forming apparatus 1. However, a printer, a facsimile apparatus, or a so-called multifunction machine having a copying function, a printing function, a fax function, a network function, and an e-mail function. Even so, it is clear that it can be implemented.

  As described above, when the present invention is carried out, it is possible to use special paper with poor fixability even without an automatic duplex printing function, and it is possible to reduce the occurrence of curling and wrinkles. .

1 is a schematic front view illustrating a schematic configuration and structure of an image forming apparatus to which the present invention is applied. 3 is a block diagram for explaining control of the image forming apparatus 1. FIG. 3 is a flowchart for explaining an operation of the image forming apparatus 1 according to the present invention. It is an example of an operation explanation display displayed on the display unit 4 when a pre-registered paper feed unit is selected. It is front sectional drawing of the image forming apparatus in which the conventional automatic double-sided printing is possible.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Image reading part 4 Display part 5 Operation input part 6 Notification apparatus 7 Operation part 10 Paper feed part 11 Feed roller pair 12 Registration roller 13 Image forming part 15 Transfer roller 16 Fixing part 16a Heat roller 16b Pressure roller 16c Heater 16d Temperature sensor 17 Discharge tray 19 Controllers 21a, 22a, 23a, 24a Paper feed roller 21 Manual paper feed tray 22 First paper feed unit 23 Second paper feed unit 24 Third paper feed unit 30 Photoconductor 31 Charging Device 32 Exposure device 33 Developing device 34 Cleaning device 40 Drive unit 41 Storage unit 42 Printer controller 43 Communication control unit 101 Image forming apparatus 102 Paper feed cassette 103 Paper feed roller 104 Feed roller 105 Registration roller 107 Photosensitive drum 108 Transfer roller 110a Heater 110 Fixing portion 111 Roller after fixing 112 discharge roller pair 114 branching unit 115 inverting portion 116 reversing rollers 117, 118 and 119 conveying rollers 120 discharge tray P Paper

Claims (5)

One or more paper feeding devices for storing and feeding paper, an image forming unit capable of forming an image on the paper, a fixing unit for fixing the image by heating and pressurizing the paper on which the image is formed, and an operation Input and display related to the operation unit,
When a sheet is fed from a specific sheet feeding device, the sheet is allowed to pass without forming an image in the image forming unit, and the sheet is discharged by being heated and pressurized by the fixing unit, and the discharged sheet An image forming apparatus, wherein a message prompting the user to place the image on the predetermined sheet feeding device is displayed on the operation unit.   The image forming apparatus according to claim 1, further comprising a storage unit that stores setting data, wherein the specific sheet feeding device and the predetermined sheet feeding device are registered in the storage unit in advance.   3. The image forming apparatus according to claim 1, wherein when the sheet is heated by the fixing unit, a temperature of the fixing unit is higher than a temperature when the image is fixed.   When an input is performed by a predetermined key of the operation unit after the message is displayed, a sheet placed on the predetermined sheet feeding device is fed and an image is formed on the sheet. The image forming apparatus according to any one of claims 1 to 3.   The image forming apparatus according to claim 1, wherein the notification device is caused to ring together with the display of the message.

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