JP2013107221A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus which prevents a nozzle down of a recording head due to attachment of paper powder flown into the image forming apparatus, has no effect on image quality such as ink blurring or strike through, and can suppress troubles of paper such as paper wrinkles or paper tear.SOLUTION: The image forming apparatus forms an image on a printing paper by jetting ink droplets from a recording head, and includes: a paper feeding stand for loading the printing paper; a liquid applying means for applying the liquid on side surfaces of the printing paper loaded on the paper feeding stand; and a liquid applying means moving mechanism capable of changing the distance between the liquid applying means and the side surface of the printing paper loaded on the paper feeding stand. The liquid applying means is a lateral surface liquid applying means for applying the liquid on the lateral surface which is in parallel to a paper feeding direction among the side surfaces of the printing paper loaded on the paper feeding stand and/or a tip end surface liquid applying means for applying the liquid to the tip end surface in the paper feeding direction among the side surfaces of the printing paper loaded on the paper feeding stand.

Description

  The present invention relates to an image forming apparatus.

  In an image forming apparatus that ejects ink droplets from a recording head to form an image on printing paper, the printing paper is supplied to an image forming unit having a recording head, and after an image is formed on the surface of the printing paper, a paper discharge tray To be discharged.

  As described above, in the image forming apparatus, the printing paper passes through the image forming unit. At this time, paper dust may be generated from the cut surface or the like of the printing paper. Then, if the generated paper dust rises in the image forming apparatus and adheres to the nozzle portion of the recording head, there is a possibility that nozzle down occurs. When nozzle down occurs, there is a problem that white streaks occur in the image and image quality deteriorates.

  Various methods have been studied to solve such problems.

  In Patent Document 1, an edge regulating unit that is provided in an ejected medium accommodation unit and that regulates the position of the edge in contact with the edge of the ejected medium and a predetermined portion on the liquid ejecting unit side have the same potential forming unit. Discloses an ink jet printer set to the same potential.

  Patent Document 2 discloses an ink jet recording apparatus in which a liquid is uniformly applied to the entire surface of a recording sheet before printing, and is then heated and dried before being used for printing.

  Patent Document 3 discloses a paper surface wiping device for printing paper that presses a uniformly wiping sheet for wiping against the surface of a running printing paper prior to printing and removes paper dust and the like from the surface of the printing paper. Has been.

  However, since Patent Document 1 needs to be equipped with the same potential forming means, there are problems such as an increase in cost and an increase in power consumption.

  In Patent Documents 2 and 3, since moisture is applied to the printing surface, there are problems such as ink bleeding and back-through when an image is formed on printing paper. In addition, when water is applied or wiped over the entire surface of the paper, wrinkles and tears may occur depending on the paper type, and it is necessary to set and control the parameters for application and wiping depending on the paper type. It was the cause of up.

  In view of the above problems, the present invention prevents paper dust from being scattered in the image forming apparatus and causing the recording head to nozzle down due to paper dust adhesion, and does not affect image quality such as ink bleeding or back-through. An object of the present invention is to provide an image forming apparatus that suppresses defects in the sheet itself such as wrinkles and tears.

  In order to solve the above-described problems, the present invention provides an image forming apparatus that ejects ink droplets from a recording head to form an image on a printing paper, a paper feeding table on which the printing paper is loaded, and a paper feeding table that is loaded on the paper feeding table. Liquid application means for applying a liquid to the side surface of the printed paper, and a liquid application means moving mechanism capable of changing the distance between the liquid application means and the side surface of the print paper loaded on the paper feed table The liquid application means includes a lateral side surface liquid application means for applying a liquid to a lateral side surface parallel to the paper feeding direction among the side surfaces of the printing paper loaded on the paper feed table, and / or An image forming apparatus is provided that is a front end surface liquid applying unit that applies a liquid to a front end surface in a paper feeding direction among the side surfaces of the printing paper stacked on the paper supply table.

  According to the present invention, the paper powder adhering to the printing paper is absorbed by wetting a part of the side surface of the printing paper loaded on the paper feed tray, so that scattering of the paper powder in the image forming apparatus is suppressed. In addition, the nozzle down of the recording head can be prevented.

  Also, the recording surface (printing surface) of the printing paper is not coated with a liquid to prevent paper dust scattering, so it affects the image quality such as ink bleeding and back-through, and the printing paper itself such as paper wrinkles and tears. Can be prevented.

  In addition, wetting a part of the side of the printing paper can prevent static electricity generation in a low-humidity environment, thus preventing multiple sheets from being fed simultaneously (multiple feeding) when feeding printing paper to the image forming device. It is also possible to improve the paper alignment (paper discharge alignment) on the paper discharge table.

Explanatory drawing of the image forming apparatus which concerns on the 1st Embodiment of this invention. Explanatory drawing of the control part of the image forming apparatus which concerns on the 1st Embodiment of this invention. Explanatory drawing of the side surface part liquid application means which concerns on the 1st Embodiment of this invention. 1 is a control flow diagram of an image forming apparatus according to a first embodiment of the present invention. Explanatory drawing of the tip surface liquid application means based on the 2nd Embodiment of this invention. Control flow diagram of image forming apparatus according to second embodiment of present invention Explanatory drawing of the side surface part liquid application means and the side surface part liquid application means which concern on the 3rd Embodiment of this invention.

Hereinafter, modes for carrying out the invention will be described with reference to the drawings, but the present invention is not limited to these examples.
[First Embodiment]
In the present embodiment, a first configuration example of the image forming apparatus of the present invention will be described.

  The image forming apparatus according to the present embodiment includes the following configuration in an image forming apparatus that ejects ink droplets from a recording head to form an image on a printing paper.

  A sheet feeding table on which printing paper is stacked; a liquid application unit that applies liquid to a side surface of a printing sheet loaded on the sheet feeding table; and a liquid coating unit loaded on the sheet feeding table and the printing sheet loaded on the sheet feeding table. And a liquid application means moving mechanism capable of changing a distance between the side surface and the side surface. The liquid application means is a lateral side surface liquid application means for applying a liquid to a lateral side surface parallel to the paper feeding direction among the side surfaces of the printing paper loaded on the paper feed table. Image forming apparatus An image forming apparatus.

  A specific example of the overall configuration of the image forming apparatus will be described with reference to FIG.

  The inkjet image forming apparatus shown in FIG. 1 is a line type image forming apparatus, and the overall configuration of the image forming apparatus will be described by taking this as an example. However, the image forming apparatus of the present invention is limited to such a form. It is not a thing.

  The image forming apparatus shown in FIG. 1 has an image forming apparatus main body 1, a paper feed tray 2 for loading printing paper 10 serving as a recording medium and feeding it to the image forming apparatus main body, and discharging the printed printing paper 10; And a paper discharge tray 3 to be stacked.

  The image forming apparatus main body 1 includes a transport unit 4 that transports the printing paper 10 from the paper feed tray 2 to the paper discharge tray 3, and an image forming unit 5 that forms an image on the printing paper 10 transported by the transport unit 4. The control means 500 is provided.

  The image forming apparatus main body 1 is provided with front and rear side plates, stays, and the like (not shown), and the printing paper 10 stacked on the paper feed tray 2 is conveyed one by one by a paper feed roller 21 and a paper feed roller 22. Paper is fed to the unit 4. As the printing paper is consumed by printing and the stacking amount is reduced, the paper feed table rises, and the uppermost portion thereof can always be in contact with the paper feed roller 21. In this case, when the paper feed roller 21 comes into contact with the top of the stacked printing paper, for example, a paper feed base upper limit sensor (not shown) is turned on so that the paper feed position can always be kept constant.

  The transport unit 4 includes a transport drive roller 41A, a transport driven roller 41B, and an endless transport belt 43 wound around these rollers 41A and 41B. A plurality of suction holes (not shown) are formed on the surface of the conveyor belt 43, and a suction fan 44 for adsorbing the printing paper 10 to the surface of the conveyor belt 43 can be disposed below the conveyor belt 43. The conveyance guide rollers 42A and 42B are held by guides (not shown) on the conveyance driving roller 41A and the conveyance driven roller 41B, respectively, and are in contact with the conveyance belt 43 by their own weight. A support member 148 is disposed on the back side of the conveyor belt 43. The transport belt 43 is supported by the support member 148 at a portion between the transport driving roller 41A and the transport driven roller 41B from the lower side. The conveyance belt 43 is rotated by the conveyance drive roller 41 </ b> A being rotated by a conveyance belt drive motor (not shown), and the printing paper 10 is adsorbed on the conveyance belt 43 by the action of the suction fan 44. Is conveyed by. The transport driven roller 41 </ b> B and the transport guide rollers 42 </ b> A and 42 </ b> B are driven by the transport belt 43 to rotate.

  An image forming unit 5 is disposed above the transport unit 4. The image forming unit 5 has a head for each color that ejects ink that becomes droplets to be printed on the printing paper 10. For example, two head modules, a black head array (hereinafter referred to as “black head portion”) 50a and a color head array (hereinafter referred to as “color head portion”) 50b, are provided.

  In the black head portion 50a, a plurality of nozzles 57 and 58 that eject ink droplets of one color (black K) to the printing paper 10 that is sucked and held on the conveyance belt 43 and conveyed are arranged in the paper width direction. It is configured as a line type recording head arranged in a line. For example, the color head unit 50b includes a plurality of nozzles 51 to 56 that eject droplets of ink of three colors (yellow Y, cyan C, and magenta M) on the printing paper 10 arranged in a line in the paper width direction. The line-type recording head can be used. The order of the colors is not particularly limited. For example, as shown in FIG. 1, the order of yellow Y, cyan C, magenta M, and black K from the downstream side in the recording medium conveyance direction indicated by arrow X (left side in FIG. 1). Can be arranged. Further, it is possible to use another secondary color, gray ink, or the like and increase the number of nozzles or the number of line type recording heads of the color head unit 50b.

  The black head portion 50a and the color head portion 50b are arranged adjacent to each other, and a printing position for ejecting ink onto the printing paper 10 on the conveyor belt 43 and an upper standby position in the drawing are independent by a head portion moving means (not shown). And can be configured to be movable. In this case, the head unit moving means is not particularly limited, and for example, the black head unit 50a and the color head unit 50b may be moved in the vertical direction by a cam mechanism. Further, the black head portion 50a and the color head portion 50b can be moved in the vertical direction by using a moving means composed of a belt and a pulley.

  Further, a black cap member (hereinafter referred to as “black cap”) 6a and a color cap member (hereinafter referred to as “black cap member”) that constitute the maintenance and recovery means for maintaining and recovering the black head portion 50a and the color head portion 50b of the image forming unit 5. 6b) (denoted as “color cap”). The black cap 6a and the color cap 6b occupy positions facing the respective head portions, and close the nozzles 51 to 58 by contacting the respective recording heads at the respective facing positions. A well-known flow path, suction means, pressure chamber, etc., connected to the black cap 6a and the color cap 6b, respectively, are arranged downstream of the black cap 6a and the color cap 6b and are in close contact with the recording head surface. Thus, a blade member for wiping can be provided.

  Furthermore, an ink supply system including a sub tank, a main tank, etc. (not shown) that supplies ink to the black head portion 50a and the color head portion 50b can be provided.

  A paper discharge tray 3 for storing the printing paper 10 is provided on the downstream side of the transport unit 4. The paper discharge tray 3 includes a pair of side fences 31 that regulate the width direction of the printing paper 10 and an end fence 32 that regulates the leading edge of the paper 10.

  The control unit 500 controls the entire image forming apparatus of the present invention, and a configuration example thereof will be described with reference to FIG. The control unit 500 is an information processing apparatus including a CPU 501, a ROM 502, a RAM 503, an NVRAM 504 that is a nonvolatile memory, a host interface (host I / F) 506, and the like.

  The control unit 500 further includes a control unit and a drive unit for controlling and driving each component of the image forming apparatus. For example, as shown in FIG. 2, the head drive control unit 508 and the head driver 509, the head unit movement motor drive units 511A and 511B, the liquid application means movement mechanism control unit 517, the transport belt drive unit 513, and the suction fan motor drive Part 514.

  Here, the head drive control unit 508 and the head driver 509 control the ink ejection operations of the recording heads of the black head unit 50a and the color head unit 50b.

  The head unit moving motor drive control units 511A and 511B are for driving and controlling the head unit moving motors 512A and 512B which are driving units of the head unit moving unit that moves the black head unit 50a and the color head unit 50b.

  The liquid application means moving mechanism control unit 517 controls each liquid application means movement mechanism to be described later. In the case of this embodiment, the lateral side surface liquid application means movement for moving the lateral side surface liquid application means is performed. It becomes a lateral side surface liquid application means moving mechanism control unit for controlling the mechanism. Further, in the second embodiment to be described later, it becomes a front end surface liquid application means moving mechanism control unit for controlling the front end surface liquid application means movement mechanism, and in the third embodiment, the lateral side surface liquid application means movement mechanism control. And / or the tip surface liquid application means moving mechanism control unit.

  The conveyor belt drive unit 513 drives a conveyor belt drive motor 512 that is a drive source of the conveyor belt 43. The suction fan motor drive unit 514 drives a suction motor 515 that rotates the suction fan 44.

  In addition to this, for example, a maintenance control means for controlling the details of the maintenance execution operation based on the operation of the black cap 6a as a maintenance means and various maintenance conditions may be provided.

  Further, the control unit 500 is connected to an I / O port 516 for inputting detection signals from various sensors and an operation panel 520 for inputting and displaying information necessary for the image forming apparatus.

  The type of detection signal input to the I / O port 516 is not particularly limited. For example, the number-of-printing-counting means 521 for counting the number of printed sheets, the position detecting means 522 for detecting the position of the paper support member, the paper size determining means 523 for determining the size of the printing paper 10, and the environmental temperature and environmental humidity are detected. Various detection signals necessary for controlling the ambient temperature, humidity sensor 524, and the like.

  The ROM 502 can preliminarily define and store a control operation for the detection signal. For example, the relationship between the number of printed sheets and the control of the lateral side surface liquid application means moving mechanism can be created and stored as a sequence table at the time of design. This is to move the horizontal side surface liquid application means by the horizontal side surface liquid application means moving mechanism when the preset number of prints is reached based on the sequence table. The setting may be changed by input.

  The CPU 501 reads and analyzes the print data in the reception buffer included in the host I / F 506, performs data rearrangement processing and the like (some image processing in some cases) by the ASIC 505, and the head. The image data is transferred to the drive control unit 508. The conversion of the print data for image output into bitmap data (print raster data) is performed by developing the image data into bitmap data using a printer driver on the host side and converting the bitmap data (print raster data) of the print data. After the creation, the print raster data is transferred to this apparatus.

  When the host I / F 506 receives print raster data, the head drive control unit 508 sends the print raster data (dot pattern data) to the head driver 509 as serial data in synchronization with the clock signal. A latch signal is sent to the head driver 509 at a predetermined timing.

  The head drive control unit 508 includes a ROM (can also be configured by the ROM 502) that stores pattern data of drive waveforms (drive signals), and a D / A converter that D / A converts the drive waveform data read from the ROM. A waveform generation circuit including an A converter and a drive waveform generation circuit including an amplifier and the like are included.

  The head driver 509 receives a clock signal from the head drive control unit 508 and serial data as image data, and a latch circuit that latches the register value of the shift register using a latch signal from the head drive control unit 508. And a level conversion circuit (level shifter) for changing the output value of the latch circuit, an analog switch array (switch means) whose on / off is controlled by the level shifter, and the like. By controlling on / off of the analog switch array, a required driving waveform included in the driving waveform is selectively applied to the actuator means of the recording head of each of the head portions 50a and 50b to drive the recording head to obtain image data. Print to form a dot pattern.

  The head unit moving motor driving units 511A and 511B operate the head unit moving motors 512A and 512B during printing and nozzle recovery operation.

  Next, the lateral side surface liquid applying means will be described with reference to FIGS.

  3A is a top view of the paper feed table 2 portion, and FIGS. 3B and 3C are cross-sectional views taken along line AA ′ of FIG. 3A. .

  A printing paper 10 is stacked on the paper feed tray 2, and a lateral side surface liquid application for applying a liquid to a lateral side surface parallel to the paper feeding direction indicated by an arrow in the side of the stacked printing paper. The apparatus 11 (11a, 11b) is provided.

  Of the side surfaces of the stacked printing paper, there are two lateral side surfaces parallel to the paper feeding direction, and the lateral side surface liquid application device can be provided on only one of them, as shown in FIG. As shown, it is preferable to provide a lateral side surface liquid application device on each of the pair of lateral side surfaces. This is because paper powder can be more prevented from scattering when there are more portions to which the liquid is applied.

  The place for installing the lateral side surface liquid device is not particularly limited. However, since liquid can be applied to the entire lateral side surface of the printing paper when feeding, as shown in FIG. It is preferable to install at or near both ends of the leading end in the paper feeding direction of the printing paper.

The lateral side surface liquid applying device is a liquid capable of changing the distance between the lateral side surface liquid applying means (12a, 12b) for applying liquid to the printing paper and the lateral side surface liquid applying means and the printing paper. It is preferable to include an application means moving mechanism (15a, 15b). (In the following description, the liquid application means moving mechanism for the lateral side surface liquid application means is “the lateral side surface liquid application means movement mechanism”, and the liquid application means movement mechanism for the distal end surface liquid application means to be described later is “tip. "Surface liquid application means moving mechanism")
It is preferable that the lateral side surface liquid application means moving mechanism is controlled by the lateral side surface liquid application means moving mechanism control unit so that the lateral side surface liquid application means can be moved to a predetermined position.

  The lateral side surface liquid applying means is not limited as long as the liquid can be applied to the side surface of the printing paper, and its material, shape, and the like are not limited. For example, the surface in contact with the printing paper is preferably made of a material that can hold a certain amount of liquid on the surface, such as a sponge, a nonwoven fabric, or a cloth. Moreover, as a shape, it can be set as flat plate shape and a roller shape, for example. Further, in order to reduce friction with the printing paper, the surface in contact with the printing paper can be formed into an uneven shape such as a wave shape.

  And it is preferable that a liquid is supplied with a tube, a pump, etc. from the liquid tank 20 (20a, 20b) so that a side surface part liquid application means can be used continuously.

  The type of liquid to be used is not particularly limited, and for example, water or an organic substance can be used. It is preferable to use water or ethanol so that it is easily available and does not harm health even if the user sucks it, and the printing paper does not change color.

  The width of the lateral side surface liquid application means is not limited, and may be the same length as one side of the lateral side surface of the printing paper to be contacted, or a part thereof as shown in FIG. Can also be provided so as to contact each other.

  The height of the lateral side surface liquid application means is not limited, and may be, for example, a height equal to or higher than the maximum loading height of printing paper. In addition, as will be described later, it is composed of liquid application means divided into a plurality of lateral sides in the height direction so that the combined height is equal to or higher than the maximum loading height of the printing paper. May be.

  And it is preferable to comprise so that the part which contacts the side surface of the printing paper loaded on the paper supply stand among the lateral side surface liquid application means can be changed according to the remaining amount of the printing paper on the paper supply stand.

  This is because when the lateral side surface liquid application means is simultaneously brought into contact with the entire lateral side surface portion of the printing paper, the printing paper on the lower stacking side has a longer contact time, so liquid is excessively supplied and the printing paper is wrinkled. There is a risk of tearing. However, by having the above-described configuration, it becomes possible to adjust the amount of liquid applied and supplied, and thus such a situation can be prevented.

  In addition, since the height of the printing paper on the paper feed tray fluctuates as a result of printing, the portion in contact with the printing paper can be changed according to the remaining amount of printing paper in the height direction of the lateral side surface liquid application means With this configuration, the liquid can be applied until the printing paper runs out.

  For this reason, it is preferable that the portion of the lateral side surface liquid application means that comes into contact with the printing paper is a portion corresponding to the printing paper on the upper portion of the printing paper loaded on the paper feed table, and is supplied to the image forming apparatus. It is preferable that the liquid is applied to the printing paper immediately before being printed.

  Specifically, for example, as shown in FIG. 3B, the lateral side surface liquid applying means is divided into a plurality of parts in the height direction (12a to 14a, 12b to 14b), and the lateral side surface liquid applying means is arranged. The moving mechanism (15a to 17a, 15b to 17b) can adjust the distance so that a desired portion of the lateral side surface liquid application unit comes into contact with the printing paper according to the height of the stacked printing paper. . In FIG. 3B, since the printing paper 10 is stacked up to the top, the top lateral side surface liquid application means 12a, 12b comes into contact with the printing paper and the other lateral side surface liquid application means (13a, 14a, 13b, 14b) are separated from the printing paper. Then, as the remaining amount of the printing paper decreases, the lateral side surface liquid application means that comes into contact with the printing paper can be changed to 13a and 13b, and then further changed to 14a and 14b. Here, although the example divided into three has been described, the present invention is not limited to this, and can be further divided into a large number.

  Further, as shown in FIG. 3 (c), the lateral side surface liquid applying means is provided with one lateral side surface liquid applying means (12a, 12b) in the height direction, and a desired one of the lateral side surface liquid applying means. It can also be set as the structure which adjusts distance by a horizontal side part liquid application means moving mechanism (15a-17a, 15b-17b) from a back surface, and contacts a height part.

  And, as the lateral side surface liquid application means moving mechanism, the stacked printing paper and the lateral side surface liquid application means are in contact with each other so that the state can be switched between and the separated state. It is not particularly limited as long as the distance can be adjusted. For example, as shown in FIG. 3A, there are a method of adjusting the distance by rotating the eccentric cams 15a and 15b by the shafts 19a and 19b, a method of configuring by a stepping motor and a rack and pinion mechanism, and the like. It is done.

  Further, while the image forming apparatus is in operation, if the state where the lateral side surface liquid application unit and the printing paper are in contact with each other is maintained, the amount of liquid supplied to the printing paper may be excessive. For this reason, it is preferable to switch between the state in which the lateral side surface liquid application means and the stacked printing paper are in contact with each other at a predetermined time and the separated state.

  The reference for switching between the state in which the lateral side surface liquid application unit and the printing paper are in contact with each other is not particularly limited, and is based on the operating time of the image forming apparatus, the number of printed sheets, and the like. Switching can be done.

  For example, when switching is performed based on the operation time (printing time) of the image forming apparatus, the image forming apparatus includes an operation time detecting unit that detects the operation time of the image forming apparatus. Then, based on the operating time detected by the operating time detecting means, the state in which the lateral side surface liquid applying means is in contact with the printing paper and the state of being separated are changed (switched) every predetermined time. Is preferred.

  Here, as a method of changing the state in which the lateral side surface liquid application unit is in contact with the printing paper and the separated state, the lateral side surface liquid application unit is moved by the lateral side surface liquid application unit moving mechanism. This can be done by moving and adjusting the distance between the stacked print sheets.

  In this way, by switching the contact / separation state between the lateral side surface liquid applying means and the printing paper every predetermined time, it becomes possible to adjust the amount of liquid supplied to the printing paper as described above, and the wrinkle on the paper is reduced. Or tearing is less likely to occur.

  The operating time here means the operating time (printing time) after the printing paper is loaded on the paper feed stand and the user issues a printing command.

  The predetermined time for switching the contact / separation state between the lateral side surface liquid application unit and the stacked printing paper is not limited. For example, it is possible for the user to arbitrarily define it, or it can be configured to determine from parameters such as the type of printing paper, environmental temperature, and environmental humidity.

  As described above, the image forming apparatus preferably includes a lateral side surface liquid application unit moving mechanism control unit that controls the lateral side surface liquid application unit moving mechanism. Furthermore, the lateral side surface liquid application means moving mechanism controller controls the lateral side surface liquid application means and the paper feed table according to the type and / or environmental temperature and humidity of the printing paper loaded on the paper feed table. It is preferable that the time for which the stacked printing paper is in contact is selected.

  This is because the degree of drying of the printing paper and the amount of liquid that can be absorbed vary depending on the type of printing paper and the environmental temperature and humidity (environmental temperature and environmental humidity).

  Specifically, for example, printing paper that has been surface-treated such as thin paper or coated paper as compared to thick paper or the like may have problems with the corrugation of the paper or the surface treatment agent when the liquid is applied excessively.

  For this reason, it is possible to obtain an optimum liquid application amount by selecting the time during which the lateral side surface liquid application means is in contact with the printing paper loaded on the basis of these parameters.

  The contact time between the lateral side surface liquid application means corresponding to the type and / or environmental temperature and humidity of the printing paper and the printing paper can be set in advance in the sequence table and stored in the ROM 502 of FIG. Then, the type and / or environmental temperature and humidity of the printing paper are detected by each detector, and based on the detection value from the detector, the lateral side surface liquid applying means according to the sequence table, the printing paper loaded on the paper feed table, , That is, the contact / separation state between the lateral side liquid applying means and the printing paper can be controlled.

  Further, it is possible to configure so that the user can set and change the contact time between the lateral side surface liquid applying means and the printing paper from the operation panel.

  The content of the control is not particularly limited, and the control may be performed so that an appropriate liquid application amount is obtained according to the above parameters. For example, a method in which the lateral side liquid application unit and the stacked printing paper are repeatedly contacted and separated, that is, after the lateral side liquid application unit and the printing paper have been in contact for a certain period of time and then separated to prevent excessive water absorption. In order to prevent the printing paper from drying, the two are brought into contact again.

  In FIG. 3 (a), side fences 7a and 7b for regulating the sheet position of the stacked printing paper are provided separately from the lateral side surface liquid applying means. However, as shown in FIG. The means may be integrated with the side fence.

  By integrating the side fence and the liquid application device, it is possible to share a moving mechanism and control for restricting the paper position and to have a simple configuration.

  An example of a control flow when printing using the image forming apparatus according to the present embodiment will be described with reference to FIG.

  First, when printing paper is set by the user on the paper feed stand and printing is instructed, the information in the sequence table is read according to the type of printing paper and the environmental temperature and humidity (temperature, humidity) information, and the lateral side liquid application means The contact / separation adjustment interval (the time interval between the contact state and the separation state) is set.

  Next, an initialization operation for setting the position of the liquid application unit is performed.

  In the initialization operation, for example, an operation of once moving to a width larger than the printing paper size width and then returning to the printing paper size width is performed to set the side fence position and the position of the lateral side surface liquid application means.

  Next, when the paper feed table is raised and the upper end portion of the printing paper loaded on the paper feed roller is pressed, the lateral side surface liquid application means is displaced to the contact position.

  Then, the printing operation is started. In the printing operation, the upper end of the stacked printing paper is detected so that the uppermost portion of the stacked printing paper is positioned in the paper feed roller unit, and the position control of the paper feed table is performed.

  A portion that is in contact with the printing paper loaded on the paper feed table of the lateral side surface liquid application means is detected, and it is determined whether or not the portion corresponding to the detected upper end of the printing paper is in contact. If it is determined that the portion of the lateral side surface liquid application unit that is in contact with the upper end of the printing paper is not the portion of the lateral side surface liquid application unit that is in contact with the printing paper, the detected printing paper Change to the part corresponding to the top edge of.

  Further, it calculates the contact or separation time of the lateral side surface liquid application unit and adjusts the contact / separation interval of the lateral side surface liquid application unit during printing, that is, contact or separation between the lateral side surface liquid application unit and the printing paper. It is determined whether the upper limit time of the current time has been reached. When the contact / separation adjustment interval has been reached, the contact / separation operation is performed when the two are in contact with each other and when they are in contact with each other, the contact is made.

  Here, the method for calculating the time during which the lateral side surface liquid application means is in contact with or separated from the printing paper is not particularly limited. For example, the time can be calculated based on the number of printed sheets, and the time is specifically measured. May be.

  Detection of the portion of the lateral side liquid application means that is in contact with the specified number of sheets until printing is completed, change operation to the part corresponding to the upper end of the printing paper, and horizontal side portion liquid application until the specified number of sheets are printed The contact / separation operation of means is repeated. Then, the operation is completed when the designated number of sheets is printed.

  According to the image forming apparatus of the present embodiment described above, the side surface parallel to the paper feeding direction out of the side surfaces of the printing paper stacked on the paper feeding table is wetted to adhere to the printing paper. Paper powder absorbs liquid. For this reason, scattering of paper dust in the image forming apparatus can be suppressed and occurrence of nozzle down of the recording head can be prevented.

  In addition, because the recording surface of the printing paper is not coated with a liquid to prevent paper dust scattering, it suppresses the effects on image quality such as ink bleeding and back-through, and defects in the printing paper itself such as paper wrinkles and tearing. It becomes possible to do.

Further, since the generation of static electricity in a low-humidity environment can be prevented by moistening the side surface of the printing paper, when feeding printing paper to the image forming apparatus, it is possible to prevent simultaneous supply (multiple feeding). It is also possible to improve paper alignment (discharge alignment) on the paper discharge table.
[Second Embodiment]
In the present embodiment, a second configuration example of the image forming apparatus will be described.

  The image forming apparatus according to the present embodiment includes the following configuration in an image forming apparatus that ejects ink droplets from a recording head to form an image on a printing paper.

  A sheet feeding table on which printing paper is stacked; a liquid application unit that applies liquid to a side surface of a printing sheet loaded on the sheet feeding table; and a liquid coating unit loaded on the sheet feeding table and the printing sheet loaded on the sheet feeding table. And a liquid application means moving mechanism capable of changing the distance between the side surfaces. The liquid application unit is a front end surface liquid application unit that applies a liquid to a front end surface in the paper feeding direction among the side surfaces of the printing paper loaded on the paper supply table. An image forming apparatus.

  Here, differences from the first embodiment will be described. Since the configuration example of the entire image forming apparatus and the control unit is the same as that described in the first embodiment, it is omitted here.

  With reference to FIG. 5, the configuration of the liquid applying unit and the peripheral portion thereof according to the present embodiment will be described.

  FIG. 5A is a cross-sectional view of the paper feed table and its peripheral portion, and FIG. 5B shows a top view of the paper feed table and its periphery. In FIG. 5B, the description of the paper supply roller 21, the paper supply roller 22, and the separation pad 23 is omitted so that the arrangement of the tip end surface liquid application means can be easily understood.

  Printing paper 10 is stacked on the paper feed tray 2, and the position of the printing paper 10 is regulated by the side fence 7.

  Since the load amount of the printing paper 10 decreases with printing, the paper feed tray 2 rises according to the remaining amount of printing paper so that the uppermost portion of the stacked printing paper is always pressed against the paper feeding roller 21. Is controlled.

  The sheet fed by the sheet feeding roller 21 is provided with an image forming unit having a head for ejecting ink that becomes droplets to be printed on a printing sheet, not shown in FIG. Carried down.

  As shown in FIG. 5A, the front end surface liquid application unit 24 is provided in the image forming apparatus main body 1, and among the side surfaces of the printing paper 10 stacked on the paper supply table 2, the front end surface in the paper feeding direction. It is arranged so that the liquid can be applied in contact with the liquid.

  The front end surface liquid application unit 24 is not limited in its configuration such as material and shape as long as it can apply liquid to the front end surface in the paper feeding direction of the side surface of the printing paper. For example, the surface in contact with the printing paper is preferably made of a material that can hold a certain amount of liquid on its surface, such as sponge, nonwoven fabric, cloth, or the like. As a shape, it can be made into flat plate shape, for example. Further, the surface in contact with the printing paper can be formed into an uneven shape such as a wave shape.

  The tip end surface liquid application means 24 is supplied with liquid by a liquid tank, tube, pump, or the like (not shown) and is in a state of holding the liquid.

  The type of liquid to be used is not particularly limited, and for example, water or an organic substance can be used. In particular, it is preferable to use water or ethanol so that it is easy to obtain, does not harm health even if the operator sucks it, and the printing paper does not discolor.

  The size of the front end surface liquid applying means 24 is not limited, and as shown in FIG. 5B, the width of the front end surface liquid applying means 24 is such that the front end surface of the printing paper can be applied with liquid (front end). The length is preferably equal to or longer than one side of the surface, but may be provided so as to contact a part of the printing paper.

  The height of the front end surface liquid application unit 24, that is, the length in the stacking height direction of the printing paper is not particularly limited, and the liquid can be applied to the front end surface of the printing paper fed to the image forming apparatus main body. It is possible to select according to the paper feed speed and the load amount of printing paper.

  For example, the height may be the same as or longer than the maximum stack of print sheets so that the liquid can be applied simultaneously to all the stacked print sheets. Further, as shown in FIG. 5A, the height can be set so as to be able to contact a part of the stacked printing paper, that is, the height at which the liquid can be applied to the printing paper at least in the vicinity of the paper feeding roller of the stacked printing paper. it can.

  The front end surface liquid application unit is configured to be able to change the distance between the front end surface liquid application unit and the front end surface of the printing paper, that is, is configured to be able to contact and separate from the front end surface (side surface) of the printing paper. Preferably it is.

  This is because if the printing paper and the front end surface liquid application means are kept in contact for a long time, the liquid will be excessively supplied to the printing paper and the printing paper may be wrinkled or torn. Because.

  Although a specific configuration is not limited, for example, it is preferable to include a tip surface liquid application unit moving mechanism that moves the tip surface liquid application unit in the horizontal direction. The apparatus further includes a front end surface liquid application unit moving mechanism control unit that controls the front end surface liquid application unit movement mechanism, and based on various control conditions, between the front end surface liquid application unit and the loaded printing paper. It is preferable that the distance can be adjusted.

  The tip end surface liquid application means moving mechanism is not particularly limited. For example, a method of configuring the distance between the two by an eccentric cam as described in the first embodiment, a stepping motor 26, and the like. A method of configuring with the rack and pinion mechanism 25 is exemplified. When liquid is applied to the front end surface of the printing paper, the front end surface liquid applying means 24 moves to the contact position of the printing paper.

  In this case, in order to prevent the paper from being pushed out by the front end surface liquid application unit, the front end surface liquid application unit is moved to the contact position in a state where the paper feed base is raised and the paper is pressed against the paper supply roller 21. It is preferable to be controlled so as to contact the front end surface of the paper.

  While the image forming apparatus is in operation, if the state where the leading end surface liquid application unit and the printing paper are in contact with each other is maintained, the amount of liquid supplied to the printing paper may be excessive. For this reason, it is preferable to switch between the state in which the front end surface liquid application unit and the stacked printing paper are in contact with each other for a predetermined time and the separated state.

  The reference for switching the state where the front end surface liquid application unit and the printing paper are in contact with each other is not particularly limited, and the switching is based on the operating time of the image forming apparatus, the number of printed sheets, and the like. It can be performed.

  For example, when switching is performed based on the operation time (printing time) of the image forming apparatus, the image forming apparatus includes an operation time detecting unit that detects the operation time of the image forming apparatus. Then, based on the operation time detected by the operation time detection means, the state where the front end surface liquid application means is in contact with the printing paper loaded on the paper feed table and the state where they are separated at predetermined intervals Is preferably changed (switched).

  Here, as a method of changing the state where the front end surface liquid application unit is in contact with the printing paper and the separated state, the front end surface liquid application unit is moved by the front end surface liquid application unit moving mechanism, This can be done by adjusting the distance between the stacked printing sheets.

  Thus, by switching the contact / separation state between the front end surface liquid application means and the printing paper every predetermined time, it becomes possible to adjust the amount of liquid supplied to the printing paper as described above. This is preferable because tearing is less likely to occur.

  The operating time here means the operating time (printing time) after the printing paper is loaded on the paper feed stand and the user issues a printing command.

  Further, the predetermined time for switching the contact / separation state between the front end surface liquid application unit and the stacked printing paper is not limited. For example, it is possible for the user to arbitrarily define it, or it can be configured to determine from parameters such as paper type, environmental temperature, and environmental humidity.

  The image forming apparatus preferably includes a front end surface liquid applying unit moving mechanism control unit that controls the front end surface liquid applying unit moving mechanism. Further, the front end surface liquid application means moving mechanism control unit causes the front end surface liquid application means and the print paper to come into contact with each other according to the type and / or environmental temperature and humidity of the printing paper loaded on the paper feed table. It is preferable to be configured to select a certain time.

  Depending on the type of printing paper and the ambient temperature and humidity, the required amount of liquid applied and the degree of liquid absorption vary. For this reason, by applying an amount of liquid corresponding to these parameters, it is possible to make the printing paper have an appropriate wetting condition, and it is possible to prevent the printing paper from being wrinkled or torn. Further, the effects of the present invention such as prevention of paper dust scattering in the image forming apparatus can be more appropriately exhibited.

  For example, paper that is surfaced like thin paper or coated paper compared to thick paper may shorten the contact time because liquid undulation or surface treatment agent may cause problems if excessive liquid is applied. Is preferred.

  Further, since the state of the printing paper changes depending on the environmental temperature and the environmental humidity, it is preferable to select the contact time so that the amount of liquid applied depends on these conditions.

  The contact time between the front end surface liquid application means and the printing paper according to the type of printing paper and / or the environmental temperature and humidity can be set in advance in the sequence table and stored in the ROM 502 of FIG. Then, according to the detection value from the detector of the type of printing paper and / or the environmental temperature and humidity, the distance between the front end surface liquid applying means and the printing paper loaded on the paper feed table according to the sequence table, that is, the front end surface The contact / separation state between the liquid applying means and the printing paper can be controlled. Information such as the type of the printing paper 10 may be configured to be automatically detected, but may be configured to be input by the user through the operation panel 520.

  Further, it can be configured such that the user can select and set the contact time between the front end surface liquid applying means and the printing paper from the operation panel 520 or the like.

  In order to prevent the paper from drying completely after the tip surface liquid application means has contacted for a certain period of time and separated according to the setting of the sequence table to prevent excessive water absorption, the application means is again applied to the printing paper after a certain period of time. It can also be contacted. Also, these operations can be repeated.

  An example of a control flow when printing using the image forming apparatus according to the present embodiment will be described with reference to FIG.

  First, when the user sets printing paper on the paper feed tray and instructs printing, the information in the sequence table is read according to the type of printing paper and the environmental temperature and humidity (temperature, humidity) information, and the tip surface liquid application means is connected. The separation adjustment interval (the time interval between the contact state and the separation state) is set.

  Next, an initialization operation for setting the position of the liquid application unit is performed.

  In the initialization operation, for example, the position setting of the tip surface liquid application unit is initialized and the home position is detected.

  Next, when the paper feed table is raised and the upper end portion of the printing paper loaded on the paper feed roller is pressed, the front end surface liquid application means is displaced to the contact position.

  Then, the printing operation is started. In the printing operation, the upper end of the stacked printing paper is detected so that the uppermost portion of the stacked printing paper is positioned in the paper feed roller unit, and the position control of the paper feed table is performed.

  Calculate the contact / separation time of the front surface liquid application means during the printing, and the contact / separation adjustment interval of the front surface liquid application means during printing, that is, the time of contact or separation between the front surface liquid application means and the printing paper. Judge whether the upper limit time has been reached. When the contact / separation adjustment interval has been reached, the contact / separation operation is performed when the two are in contact with each other and when they are in contact with each other, the contact is made.

  Here, the method for calculating the time during which the front end surface liquid applying means is in contact with or separated from the printing paper is not particularly limited. For example, the time can be calculated based on the number of printed sheets, or the time can be specifically measured. May be.

  The contact / separation operation of the front end surface liquid application unit is repeated until printing of the designated number of sheets is completed, and the operation is completed when the designated number of sheets is printed.

  According to the image forming apparatus of the present embodiment described above, the paper attached to the printing paper by wetting the front end surface in the paper feeding direction with liquid out of the side surfaces of the printing paper stacked on the paper feed table. The powder absorbs the liquid. For this reason, scattering of paper dust in the image forming apparatus can be suppressed and occurrence of nozzle down of the recording head can be prevented.

  In addition, because the recording surface of the printing paper is not coated with a liquid to prevent paper dust scattering, it suppresses the effects on image quality such as ink bleeding and back-through, and defects in the printing paper itself such as paper wrinkles and tearing. It becomes possible to do.

Furthermore, wetting the leading edge of the printing paper can prevent static electricity generation in a low-humidity environment, and therefore, when feeding printing paper to the image forming apparatus, it is possible to prevent simultaneous feeding (multiple feeding). In addition, the paper alignment (paper discharge alignment) on the paper discharge table can be improved.
[Third Embodiment]
In the present embodiment, a third configuration example of the image forming apparatus will be described.

  The image forming apparatus according to the present embodiment has the following configuration in an image forming apparatus that ejects ink droplets from a recording head to form an image on a printing paper.

  A paper feed tray on which the print paper is stacked, a liquid application means for applying a liquid to the side surface of the print paper stacked on the paper feed table, and a distance between the liquid application means and the side surface of the print paper is changed. And a liquid application means moving mechanism capable of moving. The liquid application unit includes a lateral side surface liquid application unit that applies a liquid to a lateral side surface parallel to the paper feeding direction among the side surfaces of the printing paper stacked on the paper feed table, and the liquid application unit. An image forming apparatus comprising: a front end surface liquid applying unit that applies a liquid to a front end surface in a paper feeding direction among side surfaces of a stacked printing paper.

  In other words, the image forming apparatus according to the present embodiment includes the lateral side surface liquid application device and the front end surface liquid application device described in the first embodiment and the second embodiment at the same time, and moves accompanying these liquid application devices. A mechanism is provided.

  Since the entire image forming apparatus and the configuration of the control unit are the same as those described in the first embodiment, they are omitted here.

  With reference to FIG. 7, the configuration of the liquid applying unit and the peripheral portion thereof according to this embodiment will be described.

  FIG. 7 shows a top view of the paper feed table and its peripheral part. In FIG. 7, the illustration of the paper supply roller 21, the paper supply roller 22, and the separation pad 23 is omitted so that the arrangement of the tip end surface liquid application means can be easily understood.

  As shown in FIG. 7, the image forming apparatus of the present invention includes the lateral side surface liquid applying means (12a, 12b) and the tip end surface liquid applying means 24 as the liquid applying means. In FIG. 7, the lateral side surface liquid applying means 12 a and 12 b and the side fence 7 are described as being integrated, but the present invention is not limited to such a form, and as described in the first embodiment. In addition, the lateral side surface liquid applying means and the side fence 7 may be arranged separately.

  Further, as described in the first embodiment, among the side surfaces of the printing paper, there are two lateral side surfaces parallel to the paper feeding direction, and only one of them may be used, but as shown in FIG. It is preferable to have a lateral side surface liquid application means on both lateral sides so that the liquid can be applied to both lateral sides.

  The configuration of each liquid coating apparatus and the moving mechanism attached thereto and, in some cases, the control means are the same as those described in the first embodiment and the second embodiment, and are therefore omitted here.

  Thus, by providing the lateral side surface liquid applying unit and the front end surface liquid applying unit at the same time, it becomes possible to apply the liquid to a plurality of side surfaces of the printing paper. For this reason, it is possible to further suppress the scattering of paper dust in the image forming apparatus, and it is possible to prevent occurrence of nozzle down of the recording head.

  In addition, because the recording surface of the printing paper is not coated with a liquid to prevent paper dust scattering, it suppresses the effects on image quality such as ink bleeding and back-through, and defects in the printing paper itself such as paper wrinkles and tearing. It becomes possible to do.

  Further, since the side surface of the printing paper is moistened to prevent generation of static electricity in a low-humidity environment, when feeding printing paper to the image forming apparatus, it is possible to prevent simultaneous feeding (multiple feeding). It is also possible to improve paper alignment (discharge alignment) on the paper discharge table.

  Then, as described in the first embodiment, the portion of the lateral side surface liquid application means that contacts the side surface of the printing paper stacked on the paper feed table is set according to the remaining amount of printing paper on the paper feed table. It is preferable that it can be changed.

  As described in the first embodiment, when the lateral side surface liquid application unit is uniformly in contact with the printing paper, the liquid is excessively supplied to the printing paper on the lower stacking side, There is a risk of tearing. However, by having the above configuration, it becomes possible to adjust the application and supply amount of the liquid, so that such a situation can be prevented.

  Further, by configuring the side surface portion liquid application means in the height direction so that the portion in contact with the printing paper can be changed according to the remaining amount of printing paper, the liquid is applied to the edge of the paper until the printing paper runs out. It becomes possible.

  As described in the first and second embodiments, the image forming apparatus preferably includes an operation time detecting unit that detects an operation time of the image forming apparatus. Then, based on the operation time detected by the operation time detection means, a state in which the liquid application means is in contact with the printing paper loaded on the paper feed table and a state in which the liquid application means is separated at predetermined time intervals ( It is preferable to be configured so that it can be changed.

  Here, the liquid application means for changing the contact / separation state based on the operating time may be either the lateral side surface liquid application means or the front end surface liquid application means. It is preferable because the occurrence of wrinkles and tears can be further suppressed.

  In this way, by switching the contact / separation state between the liquid application unit and the printing paper every predetermined time, an appropriate amount of liquid can be supplied to the printing paper immediately before feeding, and the printing paper is not wrinkled or torn. It becomes difficult to occur. The contact / separation state can be switched by the liquid application means moving mechanism as described in the first and second embodiments.

  Further, the image forming apparatus controls the liquid application means moving mechanism control unit, that is, the lateral side surface liquid application means moving mechanism control unit that controls the lateral side surface liquid application means movement mechanism, and the tip surface liquid application means movement mechanism. It is preferable to provide a tip surface liquid application means moving mechanism control unit. Then, the liquid application means moving mechanism controller controls the liquid application means and the print paper loaded on the paper feed table according to the type and / or environmental temperature and humidity of the print paper loaded on the paper feed table. It is preferable to be configured so as to select the time during which the contact is made.

  Note that the liquid application means moving mechanism control unit may control the contact time with the printing paper for only one of the lateral side surface liquid application means and the tip surface liquid application means, but it is better to control both of the printing paper. This is preferable because the occurrence of wrinkles and tears can be further prevented.

  As described in the first and second embodiments, the required liquid application amount and the degree of liquid absorption vary depending on the type of printing paper and the environmental temperature and humidity. For this reason, by applying an amount of liquid corresponding to these parameters, it is possible to make the printing paper have an appropriate wetting condition, and it is possible to prevent the printing paper from being wrinkled or torn. Further, the effects of the present invention such as prevention of paper dust scattering in the image forming apparatus can be more appropriately exhibited.

  As a control flow when printing using the image forming apparatus according to the present embodiment, for example, the same flow as in FIG. 4 described in the first embodiment and FIG. 6 described in the second embodiment is used. It can be carried out by carrying out simultaneously.

2 Feeding base 10 Printing paper 12a-14a, 12b-14b Lateral side surface liquid application means 15a-17a, 15b-17b Lateral side surface liquid application means moving mechanism 24 Front end surface liquid application means

JP 2011-105476 A JP 2003-165203 A JP-A-11-170484

Claims (4)

In an image forming apparatus that ejects ink droplets from a recording head and forms an image on a printing paper,
A paper tray for loading printing paper;
A liquid application means for applying a liquid to the side surface of the printing paper loaded on the paper supply table;
A liquid application means moving mechanism capable of changing a distance between the liquid application means and a side surface of the printing paper loaded on the paper feed table;
The liquid application unit is configured to apply a liquid to a lateral side surface parallel to the paper feeding direction among the side surfaces of the printing paper stacked on the paper feed table and / or on the paper feed table. An image forming apparatus, comprising: a front end surface liquid applying unit that applies liquid to a front end surface in a paper feeding direction among side surfaces of a stacked printing paper.   The portion of the lateral side surface liquid application means that contacts the side surface of the printing paper stacked on the paper feed table is changed according to the remaining amount of printing paper on the paper feed table. The image forming apparatus according to 1. The image forming apparatus includes a liquid application unit moving mechanism control unit that controls the liquid application unit movement mechanism,
The liquid application means moving mechanism control unit is configured to print the liquid application means and the prints stacked on the paper feed table according to the type and / or environmental temperature and humidity of the print paper loaded on the paper feed table. The image forming apparatus according to claim 1, wherein a time during which the sheet is in contact is selected. The image forming apparatus includes an operation time detecting unit that detects an operation time of the image forming apparatus,
Based on the operating time detected by the operating time detecting means, the state where the liquid application means is in contact with the printing paper loaded on the paper feed table and the state where they are separated are changed at predetermined time intervals. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus.

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