JPH082027A - Ink jet recording device - Google Patents

Abstract

(57) [Abstract] [Purpose] In a paper width detection device used in an ink jet recording apparatus, which optically scans a paper moving on a guide and detects the paper width of the paper by the change in the amount of reflected light. We propose a concrete structure to prevent the surface treatment layer of the guide from peeling off due to abrasion and changing the light reflectivity of the guide to cause the paper width detection to malfunction. An inkjet recording head 4 that radiates ink toward a sheet 2 on the guide 1 and a carriage 6 that moves in a direction perpendicular to the traveling direction of the sheet 2 that runs along the surface of the guide 1 and the inkjet recording head 4 described above. A paper width detection means 5 for detecting the width of the paper 2 on the guide guide 1 is provided by a change in the reflected light amount of the light irradiated toward the guide guide 1 surface, and the irradiation light from the paper width detection means 5 is provided. It is characterized in that a concave groove 1a is formed on the guide surface to be irradiated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for recording characters, images, figures and the like on an object to be recorded by ejecting ink from minute openings, and more particularly to detecting the width of a set paper. The present invention relates to improving the reliability of the paper width detecting means.

[0002]

2. Description of the Related Art FIGS. 3 and 4 show an outline of a conventional ink jet recording apparatus, in which a recording sheet 2 is composed of a plurality of roller pairs composed of a sheet conveying roller 3b and an idler 3c driven by a drive motor 3a. An aluminum plate or the like is moved along a fixed guide guide 1 curved in an arc shape.
The recording head 4 is mounted on a carriage 6, and in a state of facing the top of the curved fixed guide guide 1, the recording head 4 is moved along a guide rail 7 by a motor (not shown). It is configured to be movable at right angles to the moving direction.

The recording operation is performed by alternately repeating the printing operation in the direction of the recording head 4 and the movement of the recording paper 2. Reference numeral 5 denotes a paper width detecting means, which is attached to the carriage 6 beside the recording head 4. The paper width detecting means 5 is a reflection type photo sensor that irradiates the fixed guide 1 with the irradiation light and detects the presence or absence of the paper by the intensity of the reflected light.

That is, when the recording paper 2 is conveyed between the guide guide 1 and the recording head 4, the recording paper 2 is subjected to a black surface treatment with little reflection of light, so that the recording paper 2 has a reflectance difference between the recording paper 2 and the recording paper 2. Detect the presence of. When the carriage 6 moves and the reflection-type photo sensor 5 deviates from the right edge of the recording paper 2, it is detected that there is no recording paper, and the left edge of the paper is also detected. The width of the sheet is detected by counting the interval at which the carriage 6 moves and the edge of the sheet is detected.

[0005]

However, in the above-mentioned structure, the black surface treatment layer provided at the top of the guide guide 1 for detecting the width of the sheet is provided with the black surface treatment layer to make a difference in reflectance from the sheet. The paper becomes worn due to repeated running, and
There is a problem that the reflection type photosensor 5 makes an erroneous detection due to the exposure of the background 1b having a high reflectance as shown in FIG.

[0006]

In order to solve this problem, in the ink jet recording apparatus of the present invention, a concave groove is provided in the portion of the guide which is irradiated with the irradiation light of the above-mentioned paper detecting means, and inside this concave groove. Is characterized in that a layer having a light reflectance lower than that of the guide guide surface is formed.

[0007]

According to this structure, the inside of the concave groove formed in the guide does not come into contact with the recording paper, and the surface treatment layer formed in the concave groove is formed in order to increase the difference in reflectance with the paper. It will not come off due to wear, and there will be no abnormality in the paper width detection.

[0008]

Embodiments of the present invention will be described with reference to FIGS. 1 and 2, the same components as those of the conventional example shown in FIGS. 3 and 4 have the same reference numerals.

The difference between this embodiment and the conventional example shown in FIGS. 3 and 4 is that, in this embodiment, the recording paper 2 is prone to wear, and the top of the guide 1 for detecting the paper width is recessed. The groove 1a is provided, and a layer having a light reflectance lower than that of the guide guide surface 1 is formed in the groove 1a. Other configurations and operations are similar to those in the conventional example. In the ink jet recording apparatus of the present embodiment configured as described above, the inside of the concave groove 1a at the sheet width detection position does not come into contact with the recording sheet, and therefore the surface treatment layer is not peeled off due to abrasion and the sheet is not peeled off. The width is detected accurately and stably.

[0010]

As described above, according to the present invention, the inside of the concave groove of the guide does not contact the recording paper, and the surface treatment layer is not worn. Therefore, accurate detection can be stably performed without causing abnormality in the paper width detection due to the change in the light reflectance, and the reliability of the paper width detection is improved.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an outline of an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view showing an outline of an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 3 is a side sectional view showing an outline of a conventional inkjet recording apparatus.

FIG. 4 is a perspective view showing an outline of a conventional inkjet recording apparatus.

[Explanation of symbols]

 1 guide guide 1a concave groove 1b worn portion 2 recording paper 3a drive motors 3b and 3c paper transport roller 4 recording head 5 paper width detection means 6 carriage 7 guide rail

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G01B 11/02 G

Claims (1)

[Claims] 1. A means for causing a sheet to travel along a guide guide surface, a carriage moving in a direction perpendicular to the traveling direction of the sheet, and an ink radiating ink toward the paper on the guide guide surface. An inkjet head fixed on the carriage, and a paper fixed on the carriage for detecting the width of the paper on the guide guide surface by a change in the reflected light amount of the light irradiated toward the guide guide surface. In an ink jet recording apparatus having a width detection means, a groove is formed in a guide guide surface irradiated with the irradiation light from the paper width detection means, and a layer having a light reflectance lower than that of the guide guide surface is formed in the groove. An ink jet recording apparatus, characterized in that: