JPH05328053A - Image reader and adjustment method therefor - Google Patents

Abstract

PURPOSE:To provide an image reader which can secure parallel between an optical unit and a guide plate. CONSTITUTION:The feature of the image reader is consisting of an original placing plate which is fixed to a device main body 13 and where an original to be read is placed, the guide plate 14 which is rotatablly fixed on the original placing plate at one end of the top part of the device main body 13 and to which the original is abutted, the optical unit 1 which moves in a vertical direction to the abutting line of the original and the guide plate 14 and to which an optical system reading the original is adjustablly fixed, and an optical adjustment plate 16 which is fixed to the optical unit 1 on the surface of the original placing plate and provided with a test chart at the readable position of the optical system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading device such as a copying machine or a scanner, and more particularly to an optical adjusting mechanism and a position adjusting mechanism for a document.

[0002]

2. Description of the Related Art Generally, in an image reading apparatus, a light source such as a lamp for radiating light, an optical system for reflecting the light, an optical system such as a lens, and a C for converting the reflected light into an electric signal.
The document is read by moving the document surface by an optical unit including a photoelectric conversion element such as a CD. In such an image reading apparatus, as described in Japanese Utility Model Publication No. 3-42776, a guide plate for determining the placement position of the original is screwed to the original placing table, and the leading end of the original is placed on the guide plate. The original placement position is determined by the contact with the.

[0003]

In the above-mentioned structure, the guide plate is simply screwed to the document table. For this reason, when the guide plate is attached to or detached from the document placing table, due to errors in the mounting position, etc.
It is not always screwed in place. Therefore, there is a problem in that the placement position of the document varies, the parallelism between the optical unit and the guide plate cannot be ensured, and the document is read obliquely.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an image reading apparatus capable of ensuring the parallelism between the optical unit and the guide plate.

[0005]

An image reading apparatus of the present invention comprises an original placing table which is fixed to an apparatus main body and on which an original is placed for reading, and an upper end of the apparatus main body on the original placing table surface. A guide plate which is rotatably fixed and which comes into contact with the original, and an optical system which moves in a direction perpendicular to a contact line between the original and the guide plate and an adjustable optical system for reading the original. It is characterized by comprising a unit and an optical adjustment plate fixed to the optical unit on the surface of the original table and provided with a test chart at a readable position of the optical system.

Further, the adjusting method of the image reading apparatus of the present invention comprises the first step of reading the test chart by the optical system and determining the fixed position of the optical system based on the read result. A second step of moving the optical unit in the direction of one end of the original placing table and bringing the entire surface of the optical adjustment plate into contact with the guide plate to determine the fixing position of the guide plate. It is what

[0007]

In the image reading apparatus according to the present invention, the optical system reads the test chart provided on the optical adjustment plate, determines the fixed position of the optical system based on the read result, and further sets the optical unit to the original document. The mounting position of the guide plate is determined by moving the mounting table toward one end and bringing the entire surface of the optical adjustment plate into contact with the guide plate.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a structural diagram of an image reading apparatus according to an embodiment of the present invention. 2 and 3 are sectional views taken along the line ab of FIG. FIG. 4A is a top view when the optical adjustment plate, the guide plate, and the positioning plate are in contact with each other. FIG. 4B is a sectional view taken along the line cd of FIG.

1 and 2, 1 is an optical unit, 2 is an original placing table, 3 is an original, 4 is a mirror, 5 is a lens, 6 is an image sensor such as CCD, 7 is a light source, and 8 is an optical unit. Frame, 9 slide bearing, 10 guide shaft, 11 roller, 12 guide rail, 13
Is a body frame (apparatus body), 14 is a guide plate,
Reference numeral 15 is a positioning plate, and 16 is an optical adjustment plate.

The optical unit 1 includes a mirror 4, a lens 5,
It is composed of an optical system including an image sensor 6, a light source 7, and an optical unit frame 8. A slide bearing portion 9 that can be inserted into the guide shaft 10 is provided at one end of the optical unit frame 8, and a guide rail 12 is provided at the other end.
A roller 11 that rolls over is provided. That is, the slide bearing portion 9 is supported by the guide shaft 10,
The roller 11 is supported by the guide rail 12.
The original placing table 2 made of glass or the like is fixed on the body frame 13, and the original 3 is placed on the original placing table 2.

A drive motor (not shown) in the optical unit 1 drives the optical unit 1 to move along the guide shaft 10 and the guide rail 12. And
Light is emitted from the light source 7 in the optical unit 1,
This light is applied to the original 3. The reflected light reflected by the original 3 is further reflected by the mirror 4, and the reflected light is incident on the CCD through the lens 5 and converted into an electric signal. Thus, the original 3 placed on the original placing table 2 is read.

The guide plate 14 has two ends (14
b, 14c) are screwed to the main body frame 13, and when the original 3 is placed on the original placing table 2, the tip of the original 3 is brought into contact with the guide plate 14 as shown in FIG. The placement position of the document 3 is determined. In FIG. 4, one end 14b of the guide plate 14 is a hole having the same size as the mounting screw, and the other end 14c is the optical unit 1.
It has a long hole in the moving direction. That is, the guide plate 14 is rotatably fixed on the surface of the document table 2 in the direction of the arrow around the mounting hole 14b.

The holes provided in the positioning plate 15 are
As shown in FIG. 4, it has an elongated hole for attaching to the main body frame 13, and even if the guide plate 14 is removed, the guide plate 14 is contacted with the screw so that the position of the guide plate 14 can be seen. It is fixed.

The optical adjustment plate 16 serves as the optical unit 1 and the guide plate 14 before the image reading device of this embodiment is used, or when the image reading device of this embodiment cannot read the original 3 in parallel. In order to restore the parallelism of the optical unit 1, the optical unit 1 is mounted as shown in FIG. 1 or 3. Normally, when reading an image, it is removed from the optical unit 1 as shown in FIG. In FIG. 4, the optical adjustment plate 16 is provided with a black line test chart 16b indicating a predetermined reading width and reading position on the underside 16a of the ceiling.
Needless to say, the width, the length, and the dimension L of the black line test chart 16b are all within the design reference values. Further, in FIG. 3B, the distance A from the position where the optical adjustment frame 16 is attached to the optical unit frame 8 to the black line test chart 16b is the optical path length when using, for example, transparent glass for the document table 2. It has a length that takes into account changes.

Next, the adjusting method will be described with reference to FIGS.

As shown in FIG. 3, the optical adjustment plate 16
Is attached to a predetermined position of the optical unit frame 8, and the output signal of the image sensor 6 is observed as a waveform with an oscilloscope, for example. At this time, the image sensor 6 reads the black line test chart 16b of the optical adjustment plate 16, observes the output signal of the image sensor 6 with an oscilloscope, and reads all the black line test charts.
The position and angle of the image sensor 6, the mirror 4, or the lens 5 are adjusted.

The adjustment of the image sensor 6 after the adjustment of the mirror 4 and the lens 5 is completed is as follows. For example, in FIG. 3, when the position of the image sensor 6 is moved in the X direction or the Y direction, the reading position of the image sensor 6 moves in the x direction or the y direction on the ceiling backside 16a of the optical adjustment plate 16. The initial adjustment of the optical unit 1 is performed as described above. In addition, the mirror 4, the lens 5,
Which of the image sensors 6 is adjusted may be appropriately selected.

Next, the optical unit 1 is attached to the guide plate 1
4, the optical adjustment plate 16 is brought into contact with the guide plate 14, and the guide plate 14 is moved so that the entire surface of the guide plate 14 comes into contact with the optical adjustment plate 16. In this state, the guide plate 14 is screwed and fixed to the main body frame 13. Thereby, the guide plate 14 and the portion read by the image sensor 6 can be parallel to each other.

Further, the positioning plate 15 is brought into contact with the guide plate 14 and fixed to the main body frame 13 by screwing. Therefore, even after the guide plate 14 is attached and detached, it is possible to always attach the guide plate 14 to a fixed position by bringing the guide plate 14 into contact with the positioning plate 15.

After that, the optical adjustment plate 16 is removed, and the original 3 placed on the original table 2 is read in the state shown in FIG.

Either the initial adjustment of the optical unit 1 or the position adjustment of the guide plate 14 may be performed first.

[0023]

According to the present invention, the placement position of the original document does not vary, the parallelism between the optical unit and the guide plate can be secured, and the original document can be prevented from being read obliquely. Further, even if the guide plate is removed from the document placing table and then attached again, the guide plate is always screwed in a fixed position.

[Brief description of drawings]

FIG. 1 is a structural diagram of an embodiment of the present invention.

FIG. 2 is a sectional view of an embodiment of the present invention.

FIG. 3 is a sectional view of an embodiment of the present invention.

FIG. 4 is a structural diagram of three plates according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical unit 2 Original placing table 3 Original 4 Miller 5 Lens 6 Image sensor 7 Light source 8 Optical unit frame 9 Slide bearing part 10 Guide shaft 11 Roller 12 Guide rail 13 Main frame 14 Guide plate 15 Positioning plate 16 Optical adjustment plate

Claims (2)

[Claims] 1. An original placing table which is fixed to an apparatus main body and on which an original is placed for reading, and an upper end of an upper portion of the apparatus main body which is rotatably fixed on the original placing table surface so that the original comes into contact. And a guide plate, an optical unit that moves in a direction perpendicular to the contact line between the document and the guide plate, and an optical system that adjustably fixes an optical system for reading the document; An image reading apparatus comprising: an optical adjustment plate fixed on the above and having a test chart provided at a readable position of the optical system. 2. An original placing table fixed to the main body of the apparatus, on which an original is placed for reading, and one end of an upper portion of the main body of the apparatus, which is rotatably fixed on the surface of the original placing table, with which the original comes into contact. And a guide plate, an optical unit that moves in a direction perpendicular to the contact line between the original and the guide plate, and an optical system that adjustably fixes an optical system for reading the original, and the original mounting table surface on the optical unit. An image reading apparatus including an optical adjustment plate fixed on the above and having a test chart provided at a readable position of the optical system, wherein the test chart is read by the optical system, and based on the read result. A first step of deciding a fixed position of the optical system, and moving the optical unit in the direction of one end of the document placing table to perform the optical adjustment play. The entire surface is brought into contact with the guide plate, the adjustment method for an image reading apparatus characterized by comprising a second step of determining a fixed position of the guide plate.