JP2003285955A - Ink jet recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink jet recording device capable of suppressing curl of a recording paper sheet and minimizing accidental contact of a recording surface after recording even when an interval between guide members faced for forming a conveying passage is small. <P>SOLUTION: The ink jet recording device performs recording onto the recording paper sheet by delivering ink drop from a nozzle disposed in a recording head. A plurality of air delivery ports are formed in one guide member forming the conveying passage of the recording paper sheet after recording and positioned on the recording surface side of the recording paper sheet, and the guide member is communicated with a blowing means via an air duct. At least while the recording paper sheet after the recording moves in a region having the guide member, a controlling means controls the blowing means to be driven. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus, and more particularly, to an ink jet recording apparatus having an improved recording paper transport system after recording. 2. Description of the Related Art An ink reservoir and a recording head are associated with each other so that a negative pressure is applied to an ink discharge port, and both are connected to each other by a flexible tube. An on-demand type ink jet recording apparatus configured to move a recording sheet in a direction orthogonal to a moving direction of the recording head with a timing while sequentially recording on the recording sheet is well known. In such an ink jet recording apparatus, after recording, the recording paper in which the ink is not dried must be conveyed, and on the way, the recording surface may come into contact with the guide member facing the recording medium. Or the printed image is damaged due to contact with the paper discharge roller. As a measure for preventing the above-mentioned inconveniences, there has been proposed a configuration in which the discharge roller is formed in a disk shape with a thin plate and the peripheral surface is formed in a sawtooth shape. [0005] The discharge roller having such a configuration can extremely reduce the contact area with the recording paper, and thus has the merit that the paper can be discharged without damaging the recorded image. However, the state of the recording paper, for example, the curl (curl), or the recording surface of the recording paper being transported, which is deformed due to environmental changes in the apparatus, may cause the transport of the recording paper after recording. May come into contact with the guide member forming the path,
There was still room for improvement in the transport system. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to suppress the curl of a recording sheet and to form a convey path in order to prevent the recording sheet from curling. It is an object of the present invention to provide an ink jet recording apparatus which can prevent careless contact of the recording surface after recording even if the distance between guide members provided is small. [0010] The object of the present invention can be achieved by the following constitutions. In an ink jet recording apparatus for recording on recording paper by discharging ink droplets from nozzles provided in a recording head, one guide member for forming a conveyance path of the recording paper after recording is provided, A plurality of air discharge holes are formed in the guide member positioned on the recording surface side, and the guide member and the blowing means are communicated via an air duct, and at least the recording paper after recording is located at the position of the guide member. An ink jet recording apparatus, wherein the control means controls the blowing means to be driven while moving the area. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the configuration and image recording by an ink jet recording apparatus will be briefly described. In the following description, the term “nozzle” refers to, for example, the inside of a print head or a print head (hereinafter, referred to as a “head”).
The ink supply passage communicates with an ink storage chamber provided integrally with the ink supply chamber and has a nozzle end at one end, in other words, a tube including an ink discharge port. The term "ink ejection port" refers to only the end of the nozzle, in other words, a fine hole (opening) formed on the nozzle surface. Further, "around the ink ejection port" or "around the ink ejection port" refers to a region on the nozzle surface corresponding to the vicinity of the ink ejection port formed on the nozzle surface. . However, the "ink ejection port" may be replaced by a "nozzle" for convenience of explanation. FIG. 1 is a perspective view showing a main part of the ink jet recording apparatus. In the figure, 1 is a carriage, 2
Is a head having a number of nozzles in the vertical direction, which is integrally formed with the carriage 1. Reference numeral 3 denotes a flexible cable which achieves electrical connection between the head 2 and a control board 9 provided on the apparatus main body side. The flexible cable 3 is connected to a control board 9
And a wiring pattern printed on a flexible film. Data is transmitted between the carriage 1 and the control board 9. Reference numeral 4 denotes a carriage driving mechanism, and a motor 40
0, a pulley 410, a toothed belt 420, two guide rails 430, and the like. The carriage 1 is provided with the toothed belt 42.
It is fixed to 0, and reciprocates in the main scanning direction indicated by the arrow X while being supported by the guide rail 430 via drive rotation control for the motor 400. A box 100 shown on the carriage 1 is an ink cartridge detachably mounted on the head 2 and is configured so that, at a static pressure, the ink in the nozzles has a negative pressure at an ink discharge port. It is. More specifically, the head of this embodiment has a structure in which 128 nozzles are arranged in two rows in the vertical direction. Then, by energizing the piezo elements provided corresponding to the ink storage chambers communicating with the respective nozzles in accordance with the image signals via the flexible cable 3, the volume of the ink storage chamber is reduced. This volume reduction causes the ink to protrude from the ink ejection port at a predetermined speed, and then forms an ink droplet by the return speed of the ink at the time of volume restoration, and performs image recording using the ink droplet flying toward the recording paper ( (Print recording) can be performed, but is not shown in the figure because the configuration is publicly known. Reference numeral 5 denotes an encoder comprising scales provided at predetermined intervals on the transparent resin film. The scale is detected by an optical sensor (not shown) provided on the carriage 1.
The output information is used for controlling the moving speed of the carriage 1 to be constant. A paper transport mechanism 6 includes a transport motor 600 and transport roller pairs 610 and 620, and transports the recording paper P at a constant speed in the sub-scanning direction indicated by arrow Y. The recording paper P and the ink discharge port of the head 2 are opposed to each other, and the formation of ink droplets during the reciprocation of the head 2 in the main scanning direction and the conveyance of the recording paper P in the sub-scanning direction are combined. Thus, an image is formed on the recording paper P. FIG. 2 shows an image forming area, a cleaning area, and
It is a schematic diagram for explaining the relative positional relationship of the home position, and members (means) determined to be unnecessary in the description are omitted as appropriate. In the following drawings, the same members (means) as the members (means) already described or the members (means) having the same function are denoted by the same reference numerals. The moving range of the head 2 is the entire home position A, cleaning area B, and image forming area C at the left end in the figure. When cleaning is required, the head 2 is positioned in the cleaning area B, and then the cleaning mechanism is moved. 7 is operated to clean the nozzle surface 200 on which the ink discharge ports 201 and 203 are formed (the drawing lines are omitted because they are the same plane as the ink discharge ports 201 and 203). The cleaning mechanism 7 includes a rotation fulcrum 70
It includes a support plate 703 that rotates around 0, and a blade 705 fixed on the support plate. When power from an appropriate drive source such as a motor or a solenoid is applied to the support plate 703, the blade 705 rotates in the vertical direction (front and back on the paper) via the support plate 703, The edge (corner) slides on the nozzle surface 200 of the head 2 to perform cleaning. The head 2 having been cleaned as described above is moved to the start position of the image forming area C,
The image is formed as described above. When the image forming job is completed, the head 2 is moved to the home position A, and the ink in the nozzles is forcibly discharged by a predetermined amount through an appropriate method such as pressurization or suction. Is discharged. Thereafter, the head 2 is cleaned in the cleaning area B, moved to the home position A again,
Capped and prepared for the next image formation. FIG. 3 is a diagram schematically showing a main part of an ink jet recording apparatus provided with an improved transport system according to the present invention. In the figure, the uppermost recording paper P in the stacked state is fed rightward by the rotation of the paper feed roller 690 in accordance with the image recording process.
40, 650 and an arc-shaped first guide member 800 and a second guide member 810 provided so as to face each other to form a conveyance path, and rise, while being conveyed to the left. Then, while being horizontally conveyed on the third guide member 820, image recording by the head 2 is executed according to the principle described with reference to FIG. The recording sheet P after recording is further horizontally conveyed to the left while receiving the action of the driving roller 660 and the driven roller 670 functioning as the first sheet discharging roller. Hereinafter, when both rollers 660 and 670 are collectively referred to as a first discharge roller. The specific configuration of the first paper discharge roller will be described separately. Downstream of the first paper discharge roller, a lower guide member 830 and an upper guide member G are horizontally provided facing each other, and a plurality of air discharge holes 850 are formed in the upper guide member. The member G is in communication with a blowing means F including a fan or the like via an air duct D. Here, the communication means that the path of the air flow generated when the air blowing means F is driven continues to the upper guide member G. More specifically, the air duct D hermetically seals the upper guide member G at one end, and hermetically seals the mounting frame (not shown) of the blower F at the other end. An air flow generated by the urging (driving) of the blowing means F is discharged onto the recording paper P through the air discharge holes 850. Accordingly, in this area, the recording paper P is conveyed to the left while being pressed against the lower guide member 830 by the discharged airflow. When viewed in the recording paper transport direction, the air duct D
Is located at a position close to both rollers so as to be able to act on the recording paper immediately after passing through the clamping point between the driving roller 660 and the driven roller 670. As described above, since the recording paper P is subjected to the action of the discharge airflow immediately after the image recording to suppress the deformation or correct the deformation, the recording surface of the recording paper comes into contact with the upper guide member G. Can be suppressed. The recording paper P conveyed while receiving the above-described action is eventually nipped by the second paper discharge roller 680 and discharged onto the paper discharge tray T. The drive control of the blowing means F is performed by control means S comprising a CPU. Specifically, the blowing means F
Is started by the control means S determining a change in output when the photo sensor 900 detects the leading edge of the recording paper P. The drive control is terminated, for example, by detecting the recording paper of the photo sensor 900. The signal is used as a trigger to operate the timer, and the count is increased by the timer selected in accordance with the size information in the recording paper conveyance direction. The size information of the recording paper P can be obtained by an appropriate sensor or by a key operation of the user. The operation time of the timer for turning off the blower F is determined by the recording time used. The time until the trailing edge of the paper passes through the second paper discharge roller 680 is set for each size. It is preferable that the air discharge holes 850 are provided so that the effect of the discharge air on the recording paper P is substantially the same everywhere. FIG. 4 is a schematic diagram for explaining the structure of the first paper discharge roller. The drive roller 660 is driven by a drive shaft J1.
A plurality of rubber rollers 661 having a short width and press-fitted thereon.
It is composed of The drive shaft J1 is connected to a power drive source composed of a motor via a gear train. However, this structure can be implemented by a known mechanism as appropriate and is not directly related to the present invention. The illustration is omitted. The driven roller 670 includes a driven shaft J2 and a pair of driven rollers 67 disposed on the driven shaft J2 at a predetermined interval.
1 and the rubber roller 66
1 is provided. The driven rollers 671 can rotate independently of the driven shaft J2, and each driven roller 671 is pressed by the rubber roller 661. Further, the driven roller 671 is made of a material having a high water repellency.
E (polytetrafluoroethylene resin) was used. The width of the outer peripheral portion of the driven roller 671 in contact with the recording paper was about 0.8 mm. FIG. 6 shows a side sectional shape of a driven roller. In the above-described embodiment, the attitude of the recording paper during the conveyance of the recording paper after recording is regulated by discharging the air flow pressurized from the atmospheric pressure to the recording surface side of the recording paper. A belt having a plurality of suction holes on its side may be provided rotatably, and the recording paper may be sucked and conveyed onto the belt via suction means. The second paper discharge roller 680 is also provided by the first paper discharge roller 680.
A configuration similar to that of the paper discharge roller may be employed. According to the present invention, the conveyance state or the conveyance posture of the recording paper after recording can be regulated with a simple configuration, and the recording image surface of the recording paper can be prevented from contacting the guide member or the like.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a main part of an ink jet recording apparatus. FIG. 2 is a schematic diagram for explaining a relative positional relationship between an image forming area, a cleaning area, and a home position. FIG. 3 is a diagram schematically showing a main part of an ink jet recording apparatus provided with an improved conveyance system according to the present invention. FIG. 4 is a schematic diagram for explaining a configuration of a first paper discharge roller. FIG. 5 is a diagram showing a side sectional shape of a driven roller. [Description of Signs] 1 Carriage 2 Recording head (head) 3 Flexible cable 4 Carriage drive mechanism 5 Encoder 6 Paper transport mechanism 660 Drive roller 670 Follower roller 830 Lower guide member 850 Air discharge hole D Air duct F Blower means G Upper guide Member P Recording paper S Control means

Claims (1)

Claims: 1. An ink-jet recording apparatus that performs recording on recording paper by discharging ink droplets from nozzles provided on a recording head, and one guide member that forms a conveyance path of the recording paper after recording. A guide member positioned on the recording surface side of the recording paper, a plurality of air discharge holes are formed, and the guide member and the blowing means are communicated via an air duct, and at least recording after recording is performed. An ink jet recording apparatus, wherein the control unit controls the air blowing unit while the paper is moving in the area where the guide member is located.