JP2016016586A5 - - Google Patents

Description

According to a second aspect of the present invention, a plurality of droplet discharge heads of the head unit are fixed while fixing a head unit in which a plurality of droplet discharge heads for discharging droplets from nozzles are arranged in a predetermined arrangement and conveying a recording medium. In the image forming apparatus for forming an image by ejecting liquid droplets from the nozzles, the image forming apparatus includes support means for supporting the plurality of liquid droplet discharge heads so that their positions can be changed. There is performed the position changed to a desired position with respect to the direction you orthogonal to the conveyance direction of the recording medium, it is characterized in that an image is formed by ejecting liquid droplets while supporting in that position.

1 is a perspective view illustrating a configuration example of a serial type ink jet recording apparatus according to a first embodiment. The side view which shows the structural example of the mechanism part of the inkjet recording device of FIG. FIG. 3 is an external perspective view of the droplet discharge head as viewed from the nozzle surface side. The typical top view which looked at the droplet discharge head and the holding plate from the nozzle surface side. The typical top view which shows the structure which fixed the yoke part which is a structural member of a voice coil actuator to the base | substrate. The typical top view which shows the structure in the yoke part fixed to the base | substrate. Sectional drawing explaining the structure of the voice coil actuator which supports a droplet discharge head so that movement to a base | substrate is possible. Enlarged view schematically showing a driving coil C and a permanent magnet M for explaining the driving principle of the voice coil actuator G. FIG. 4 is an explanatory diagram of the movement of a droplet discharge head by two voice coil actuators G that support the droplet discharge head at its end. It is a figure for demonstrating arrangement | positioning of the voice coil actuator concerning a modification, and the typical top view which looked at the droplet discharge head and the holding plate from the nozzle surface side. It is a figure for demonstrating arrangement | positioning of the voice coil actuator concerning another modification, and the typical top view which looked at the droplet discharge head and the holding plate from the nozzle surface side. FIG. 3 is an explanatory diagram illustrating an example of a position change of a droplet discharge head during high resolution printing in a serial type ink jet recording apparatus. Sectional drawing which shows the structural example of the line-type inkjet recording device concerning 2nd embodiment. The top view which looked at the line type head from the nozzle surface side. The perspective view which looked at the array base which attaches a some droplet discharge head from the nozzle surface opposite side. Explanatory drawing of the position detection in the reference position adjustment of a droplet discharge head. It is explanatory drawing of an example of the position change of the droplet discharge head in a line type inkjet recording device, (a) is at the time of high-speed printing mode, (b) is at the time of high-resolution printing mode. Explanatory drawing of the flow of a reference position adjustment. Explanatory drawing of the position change with respect to linear expansion of a droplet discharge head.

Figure 8 is an enlarged view schematically showing a driving coil C and a permanent magnet M in order to explain the principle of driving the voice coil actuator G. The driving coil C is a planar coil parallel to the base 10 and has a spiral shape in which each side forms a straight line. The driving coil C includes a right side Ca, a left side Cb, an upper side Cc, and a lower side Cd. In FIG. 8, for the sake of convenience, the driving coil C is illustrated as being wound several times with an electric wire, but is actually wound several tens of times.

FIG. 11 shows a configuration in which driving coils C are disposed at the four corners of the holding plate 5 of the droplet discharge head 1 and voice coil actuators G are disposed at the four corners. In this configuration, the droplet discharge head 1 is moved by a smaller number of voice coil actuators G than in FIG.

In either configuration, adjusting the current supplied to the actuating coil C of a plurality of voice coil actuators G. Thereby, the droplet discharge head 1 can be moved to the base 10 in the X-axis direction, the Y-axis direction, or the rotation direction, and can be supported by being changed to a desired position.

On the other hand, during high-speed printing, the recording sheet 130 that has stopped, the forward carriage (not shown) is moved in the X-axis direction, recording a plurality rows corresponding to the arrangement number of Bruno nozzle. Thereafter, after the recording paper 130 is conveyed by a predetermined amount, the next plurality of lines are recorded on the return path in which the carriage 101 is moved in the X-axis direction. At this time, a voice coil actuator is provided by an actuator control means (not shown) so that the position of the nozzle 3 is the same with respect to the carriage base 10 in the forward path and the return path in which the carriage (not shown) moves in the X-axis direction. G is controlled.
As described above, the serial type ink jet recording apparatus 100 can perform high resolution printing and high speed printing.

FIG. 16 is an explanatory diagram of position detection in the reference position adjustment of the droplet discharge head.
The ink jet recording apparatus includes a position detection sensor 50 used for reference position adjustment. In FIG. 16, a line-type sensor is illustrated as the position detection sensor, but a scan-type sensor may be used. The detection accuracy of the position detection sensor 50 is preferably at least twice the target resolution. For example, if an image is formed with a resolution of 600 dpi, a position detection sensor capable of obtaining a detection accuracy of 1200 dpi or higher and a detection accuracy of 2400 dpi or higher is preferable if an image formation with a resolution of 1200 dpi is performed.

As shown in FIG. 16A, ink droplets are ejected from the nozzle at the extreme end in the X-axis direction of the droplet ejection head 1 that performs reference position adjustment, and the position of the formed dots is detected on the recording paper by the position detection sensor 50. Detect with. Then, the voice coil actuator G is driven to change the position of the droplet discharge head 1 so that the ideal reference position shown in FIG. By selectively driving the plurality of voice coil actuators G, the position of the droplet discharge head 1 can be moved in the X-axis direction, the Y-axis direction, or the rotation direction. Therefore, adjustment is made to the reference position of the head so that the dot position, the width between dots, the parallelism, and the like are optimized.

(Aspect B)
A head unit such as a line-type head 420 in which a plurality of droplet discharge heads 1 that discharge droplets from the nozzle 3 are arranged in a predetermined arrangement is fixed, and liquid is discharged from the plurality of droplet discharge heads of the head unit while conveying a recording medium. In an image forming apparatus such as a line type ink jet recording apparatus 400 that ejects droplets to form an image,
A support means, such as a voice coil actuator G for supporting the plurality of the droplet discharge head repositionable respectively, nozzle positions of the plurality of droplet ejection heads with respect to the direction you orthogonal to the conveyance direction of the recording medium by the supporting means The position is changed to a desired position, and an image is formed by ejecting liquid droplets while supporting the position.

In (aspect B), as described in the above-described second embodiment, the support means, a plurality of droplet discharge heads 1 a - 1 f, repositionable in relation to the direction you orthogonal to the conveyance direction of the recording medium To support. This support means, by changing the position of the droplet discharge head so that with respect to the direction in which the position of the nozzles is orthogonal to the conveyance direction of the recording medium reaches a desired position, the liquid from the liquid droplet ejection head while supporting in that position Image formation is performed by discharging droplets.
For example, the position of each droplet discharge head with respect to the frame body such as the array base is changed by the support means so that the nozzle positions of the plurality of droplet discharge heads overlap with the conveyance direction of the recording medium. By discharging, high-speed printing becomes possible. In addition, the position of each droplet discharge head relative to the frame body such as the array base is changed by the support means so that the nozzle positions of the plurality of droplet discharge heads are shifted with respect to the conveyance direction of the recording medium. By discharging, high resolution printing becomes possible. Therefore, even if the number of nozzles of the droplet discharge head itself and the nozzle density are the same, high-speed printing or high-resolution printing is possible compared to a configuration in which the droplet discharge head is fixed to the frame. It becomes.

(Aspect C)
In (Aspect A) or (Aspect B), as support means, a yoke plate such as a pair of yoke portions E fixed to the apparatus main body side such as a base, an N pole and S fixed on one inner side of the yoke plate A voice coil motor type actuator such as a voice coil actuator G, which is composed of a magnetic field generating member such as a permanent magnet M having a pole and a driving coil C fixed to the droplet discharge head 1 and facing the magnetic field generating member, is used. .

(Aspect F)
In any one of (Aspect C 1 ) to (Aspect E), the movement distance of the droplet discharge head by the actuator of the voice coil motor system is in the range of 0 to 200 [μm]. According to this, as described in the above embodiment, the position of the droplet discharge head 1 can be changed within one pitch of the nozzle.

DESCRIPTION OF SYMBOLS 1 Droplet discharge head 2 Nozzle plate 3 Nozzle 4 Frame member 5 Holding plate 6 Ball bearing 7 Head pressing part 8 Screw 10 Base body (frame body)
10a Opening 50 Position detection sensor
DESCRIPTION OF SYMBOLS 100 Serial type inkjet recording device 400 Line type inkjet recording device 411 Droplet discharge device 413 Head holder 420 Line type head 442 Array base (frame body)
462 Opening G Voice coil actuator C Coil E Yoke part M Permanent magnet

Claims (10)

In an image forming apparatus that performs image formation by ejecting liquid droplets while moving a liquid droplet ejection head that ejects liquid droplets from a nozzle in a direction orthogonal to the conveyance direction of the recording medium.
A support means for supporting the droplet discharge head so that the position of the droplet discharge head can be changed is provided, and the position of the nozzle of the droplet discharge head is changed to a desired position in the transport direction by the support means, and the position is supported at that position. An image forming apparatus for forming an image by discharging droplets in a state. Forming an image by fixing a head unit in which a plurality of droplet discharge heads that discharge droplets from the nozzles are arranged in a predetermined arrangement, and discharging the droplets from the plurality of droplet discharge heads of the head unit while conveying the recording medium In an image forming apparatus that performs
A support means for supporting the plurality of the droplet discharge head repositionable respectively desired position nozzle positions of the plurality of droplet ejection heads with respect to the direction you orthogonal to the conveyance direction of the recording medium by said support means The image forming apparatus is characterized in that the position is changed so that the image is formed and the liquid droplets are ejected while being supported at the position to form an image. 3. The image forming apparatus according to claim 1, wherein a pair of yoke plates fixed to a frame body on which the droplet discharge head is mounted on the apparatus main body and one inner side of the yoke plate are fixed as the support means. a magnetic field generating member having N and S poles that are fixed to the liquid droplet ejection head, a voice coil comprising a drive coil opposite to the magnetic field generating member in space between the said pair of yoke plates An image forming apparatus using a motor type actuator.   4. The image forming apparatus according to claim 3, wherein an end portion of the droplet discharge head in the transport direction of the recording medium and an end portion in a direction perpendicular to the transport direction are supported by the voice coil motor type actuator. An image forming apparatus, wherein at least one of an end portion in the transport direction or an end portion in a direction orthogonal to the transport direction is supported by a plurality of voice coil motor type actuators.   5. The image forming apparatus according to claim 3, wherein the droplet discharge head is supported by the frame body via a ball bearing. 6. The image forming apparatus according to claim 3, wherein a moving distance of the droplet discharge head by the voice coil motor type actuator is in a range of 0 to 200 [μm]. apparatus.   7. The image forming apparatus according to claim 2, wherein the support means changes the position of the plurality of droplet discharge heads so that the nozzle positions of the plurality of droplet discharge heads overlap with each other in the transport direction. The high-speed printing mode for supporting each droplet discharge head and the support means change the position of the plurality of droplet discharge heads so that the nozzle positions of the plurality of droplet discharge heads are shifted with respect to the transport direction. And an image forming apparatus characterized by having a high resolution printing mode for supporting the image forming apparatus.   8. The image forming apparatus according to claim 1, further comprising a position detection unit that detects a position of a droplet ejected from a nozzle of the droplet ejection head, based on a detection result of the position detection unit. An image forming apparatus characterized in that the position of the droplet discharge head is changed by the supporting means to adjust the droplet discharge head to a predetermined reference position.   9. The image forming apparatus according to claim 8, wherein a history of detection results of the position detection unit is accumulated, a change in the position of the droplet discharge head is predicted based on the history of the detection results, and based on the prediction. An image forming apparatus characterized in that the position of the droplet discharge head is changed by the supporting means to adjust the droplet discharge head to a predetermined reference position.   10. The image forming apparatus according to claim 8, wherein information on characteristics or temperature of the liquid ejected from the nozzle is acquired, and the liquid droplet ejection head is positioned by the support unit based on the information on the characteristics or temperature of the liquid. An image forming apparatus characterized by changing the liquid droplet ejection head to a predetermined reference position.

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