JPH0825315B2 - Image printer head - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head of an image printing apparatus that performs gradation expression of a pixel, which is the minimum unit of an image, by changing a recording area in the pixel. It is a thing.

[Conventional technology]

In an image printing apparatus in which an image is composed of a set of pixels, which is the minimum unit, and each pixel is recorded and transferred based on the image information of each pixel, in order to perform gradation expression in each pixel, printing in the pixel is performed. A method of changing the area or changing the print density of pixels is adopted.

FIG. 2 is a side view showing a head portion of an image printing apparatus which performs gradation expression of each pixel by changing a printing area in the pixel. In the figure, 1 is a transfer roller (head roller), 2 is an auxiliary roller that rotates in contact with the transfer roller 1, 3 is an ink supply roller that rotates in contact with this auxiliary roller 2, and 4 is an ink supply roller 3. It is a supply ink of. As shown in FIG. 3, the transfer roller 1 has a strip-shaped convex surface 1a protruding from the outer peripheral surface thereof, and the width W of the convex surface 1a is set to correspond to the size of one pixel. Has been done. The outer peripheral surface of the auxiliary roller 2 is brought into contact with the convex surface 1a so as to rotate, and the tip end surface of the blade 5 formed wider than the width W of the convex surface 1a is the blade 5 When the actuator 6 provided on the transfer roller 1 is turned on, the entire surface in the width direction of the convex surface 1a of the transfer roller 1 is brought into contact with the structure.

That is, by turning on the actuator 6 based on the image information for each pixel, the tip end surface of the blade 5 is contacted with the entire convex portion surface 1a of the transfer roller 1 in the width direction and is supplied to the convex portion surface 1a. The attached ink 4a is scraped off to change the printing area of the pixels printed on the paper surface 7. FIG. 4 shows a state in which the supplied and adhered ink 4a is scraped off by the tip surface of the blade 5 on the convex surface 1a of the transfer roller 1, and in each pixel divided by the length L in the drawing, The white portion is the ink scraping portion (ink scraping area) generated by the scraping operation of the deposited ink by the blade 5. That is, it is possible to express the gradation for each pixel printed on the paper surface 7 by the area ratio of the ink adhered portion and the scraped portion on the convex surface 1a of the transfer roller 1. In FIG. 2, 8 is a drain receiver for the ink scraped off by the blade 5, 9 is a cleaning blade for scraping off the ink remaining on the convex surface 1a after printing on the paper surface 7, and 10 is the cleaning blade 5. It is a drain receiver for scraped ink.

[Problems to be solved by the invention]

However, according to the head of such a conventional image printing apparatus, the tip surface of the blade 5 that scrapes off the ink 4a supplied and adhered to the convex surface 1a of the transfer roller 1 has the convex surface 1a when the actuator 6 is turned on. There is a problem in that when the ink comes into contact with the surface of the convex portion 1a, it bounces, resulting in defective scraping of the ink and impairing gradation expression.

[Means for solving problems]

The present invention has been made in view of such problems,
A blade for scraping off the ink supplied and attached to the outer peripheral surface of the head roller is arranged so as to be always in contact with this outer peripheral surface, and the blade is moved in the width direction on the outer peripheral surface of the head roller by using actuator means. It is designed to slide.

[Action]

Therefore, according to the present invention, the blade for scraping the ink moves in the width direction while always contacting the convex surface of the head roller.

〔Example〕

Hereinafter, the head of the image printing apparatus according to the present invention will be described in detail. FIG. 1 is a schematic configuration perspective view showing an embodiment of this head. In the figure, the same symbols as those in FIG. 3 indicate the same components, and the description thereof will be omitted. That is, the blade 11 is arranged so that the tip surface of the transfer roller 1 is always in contact with the convex surface 1a of the transfer roller 1, and the amount of insertion of the tip surface of the blade 11 in the width direction of the convex surface 1a is determined by the actuator 12 It has a structure that can be changed by the driving force of. That is, with respect to the width direction of the convex surface 1a of the transfer roller 1, the entire front end surface (blade surface) of the blade 11 can be slid while being in contact with the convex surface 1a, and the blade is always 11 is the transfer roller 1
The blade 11 is arranged so as to be in contact with a part of the convex surface 1a, and the actuator 12 attached to this blade 11
Drive force of the blade 11 to the convex surface of the transfer roller 1.
The structure is such that it can be slid in the width direction of 1a.

In the head of the image printing apparatus configured as described above, the actuator 12 is driven based on the image information of each pixel, that is, in the width direction of the convex surface 1a of the tip surface of the blade 11. The insertion amount is changed based on the image information for each pixel, and the change of the insertion amount changes the scraping amount of the adhered ink 4a on the convex surface 1a. In other words, a change in the amount of insertion of the tip surface of the blade 11 changes the ink scraping area on the convex surface 1a of the transfer roller 1, and this change in the ink scraping area enables gradation expression.

In the head of the image printing apparatus that performs such a basic operation, the tip end surface of the blade 11 always contacts the convex surface 1a of the transfer roller 1 and slides along the width direction of the convex surface 1a. , There is no occurrence of bounce between the surface of the convex surface 1a, and the ink scraping failure due to the bouncing like the head of the conventional image printing device does not occur, and this ink scraping failure causes The occurrence of gradation reproduction defects is prevented.

〔The invention's effect〕

As described above, according to the head of the image printing apparatus of the present invention, the blade for scraping off the ink supplied and attached to the outer peripheral surface of the head roller is arranged so as to be always in contact with the outer peripheral surface, and the actuator means is provided. This blade is slid on the outer peripheral surface of the head roller in the width direction of the head roller, so there is no blade bouncing between the outer peripheral surface and the surface of the head roller. And the occurrence of defective gradation reproduction due to defective ink scraping is prevented.

[Brief description of drawings]

FIG. 1 is a schematic configuration perspective view showing an embodiment of a head of an image printing apparatus according to the present invention, FIG. 2 is a side view showing a head of a conventional image printing apparatus, and FIG. 3 is a transfer roller portion in this head. FIG. 4 is a perspective view of the schematic configuration of FIG. 4 and FIG. 1 ... Transfer roller, 1a ... Convex surface, 4a ... Supply ink, 11 ... Blade, 12 ... Actuator.

Claims (1)

[Claims] 1. A head roller, a blade which is arranged so as to be always in contact with the outer peripheral surface of the head roller, and scrapes off the ink supplied and adhered to the outer peripheral surface, and the blade in the width direction on the outer peripheral surface of the head roller. A head of an image printing apparatus, comprising an actuator means for slidingly moving the head.