JPH07184002A - Image reader - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] An image reading apparatus having a configuration of reading a transparent document placed on a document table using a line image sensor, and reading the transparent document according to a small number of parts. A transparent manuscript table 11 on which a manuscript is placed, an optical unit 14 including a line image sensor for reading the manuscript to be placed, and a manuscript cover body having a transmissive light source 20 for irradiating the manuscript table with light are provided. When the transparent document is read by moving in the sub-scanning direction while the optical unit and the transmissive light source are opposed to each other, inside the document lid,
A slider member configured to include a rack 25 extending in the sub-scanning direction, a unit for mounting a transmissive light source, a motor 27 having a pinion meshing with the rack, and a movable inside the document lid body. And a guide member that holds the engagement between the pinion and the rack.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus having a structure in which a transparent image placed on a document table is read by using a line image sensor, and more particularly, an image which realizes reading of a transparent image according to a small number of parts. Regarding the reader.

An image reading device has a function of reading image information of an original using a line image sensor, and there is also a demand for a transparent original such as an X-ray film to be read.

In response to such a read request for a transparent original,
It is necessary to construct a structure that allows a transparent document to be read according to a simple structure.

[0004]

2. Description of the Related Art FIG. 6 shows a conventional structure of an image reading apparatus for reading both a reflective original and a transparent original.

In the figure, 10 is a housing, 11 is a manuscript table made of transparent glass, which is provided on the upper surface of the housing 10 and on which a manuscript to be read is placed, and 12 is a rotation fulcrum shaft. A document pressing cover which opens and closes around the center of the document, and which is provided with a diffusion plate 13 on the surface that comes into contact with the document table 11, and uses this diffusion plate 13 to fix the document placed on the document table 11. Is an optical unit and is a line image sensor 1 for reading image information of a document placed on the document table 11.
5 and a reflection light source 1 for illuminating a document placed on the document table 11.
6 and a lens / reflection mirror for forming an image of the document surface on the line image sensor 15.

Reference numeral 17 is a motor for moving the optical unit 14 in the sub-scanning direction (direction orthogonal to the scanning direction of the line image sensor 15) by using the belt 18.
Reference numeral 19 is a carrier shaft for guiding the movement of the optical unit 14, and 20 is a transmissive light source provided in the original pressing cover 12, which is provided with the original table 11 via the diffusion plate 13.
For illuminating a document placed on the document holding device, reference numeral 21 denotes a motor provided in the document holding cover 12 for moving the transmissive light source 20 in the sub-scanning direction by using the belt 22, and 23 denotes the inside of the document holding cover 12. Is a carrier shaft for guiding the movement of the transmissive light source 20, and 24 is a power source for the light source provided in the document pressing cover 12 for supplying power to the transmissive light source 20.

In the conventional image reading apparatus thus constructed, when the reflection original is placed on the original table 11, the reflection light source 16 is turned on and the motor 17 moves the optical unit 14 in the sub-scanning direction at a constant speed. Then, in response to this movement processing, the line image sensor 15 processes the image information of the reflection original illuminated by the reflection light source 16 so as to read it.

When the transparent original is placed on the original table 11, the transparent light source 20 is turned on, the motor 17 moves the optical unit 14 in the sub-scanning direction at a constant speed, and in synchronization with this movement. The motor 21 moves the transmissive light source 20 in the sub-scanning direction at the same speed, and in response to this movement process, the line image sensor 15 processes the image information of the transmissive original illuminated by the transmissive light source 20 so as to read it. .

[0009]

However, according to such a conventional technique, the transparent light source 2 is provided in the original pressing cover 12 in order to enable the reading of the transparent original.
In addition to 0, since the belt 22 and the carrier shaft 23 have to be provided, there is a problem that the number of constituent parts increases and the image reading apparatus becomes large and expensive.

The present invention has been made in view of the above circumstances and has a structure in which a transparent original placed on an original platen is read by using a line image sensor. An object is to provide a new image reading device that realizes reading.

[0011]

In order to achieve this object, according to the present invention, a transparent manuscript table provided on the upper surface of the housing and on which a manuscript to be read is placed, and inside the housing. An optical unit having a line image sensor for reading a document placed on the document table, a diffuser plate on a surface contacting the document table, and a transmission light source for irradiating the document table with light through the diffuser plate. Equipped with a document lid for interior,
In an image reading apparatus having a configuration of reading a transparent original to be read by moving the optical unit and a transmissive light source in a direction (sub-scanning direction) orthogonal to the scanning direction of the line image sensor while facing each other, an original lid Inside the document, a rack extending in a direction orthogonal to the scanning direction of the line image sensor is provided, and a unit for mounting a transmitted light source is provided with a motor having a pinion that meshes with the rack and inside the document lid. It is configured to include a slider member that enables smooth movement in the above, and a guide member that holds the engagement between the pinion and the rack by a sandwiching structure with the pinion.

Here, this rack is provided at a substantially central position on the upper surface of the inside of the document cover, or on the diffusion plate of the document cover. Further, the unit for mounting the transmissive light source is made of a molding material, the slider member and the guide member are integrally formed, and a socket for the transmissive light source and focusing of the light emitted from the transmissive light source are formed in this unit. A unit that mounts a transmissive light source, or adopts a structure that forms a reflector with an integrated structure,
In some cases, a printed circuit board is used as a base.

[0013]

According to the present invention, when the motor provided in the unit for mounting the transmitted light source rotates, the pinion of the motor moves in the sub-scanning direction while using the rack formed inside the document cover as the guide rail. According to this movement processing, the unit for mounting the transmitted light source moves in the sub-scanning direction while sliding on the slider member. At this time, the guide member realizes the meshing between the pinion and the rack by the sandwiching structure with the pinion.

According to this moving process, the transmissive light source moves in the sub-scanning direction while facing the optical unit, so that the transparent original can be read by the line image sensor of the optical unit.

As described above, according to the present invention, the transmission light source can be moved without providing a belt or a carrier shaft for moving the transmission light source inside the original cover as in the prior art. Thus, it becomes possible to realize the reading of a transparent original according to the smaller number of parts than the conventional technique.

[0016]

EXAMPLES The present invention will be described in detail below with reference to examples. FIG. 1 shows an embodiment of an image processing apparatus equipped with the present invention. In the figure, the same components as those described in FIG. 6 are denoted by the same symbols.

Reference numeral 25 denotes a rack provided on the upper surface of the inside of the document pressing cover 12, which is provided at a substantially central position of the document pressing cover 12 and has rails having tooth grooves arranged in the sub-scanning direction. The rack 25 is integrally formed with the document pressing cover 12 when the document pressing cover 12 is made of a molding material such as resin.
Reference numeral 26 is a self-propelled transmissive unit for mounting the transmissive light source 20. The self-propelled transmissive unit 26 is provided with a motor 27 and moves in the sub-scanning direction in the document pressing cover 12 according to the drive of the motor 27.

As can be seen from this figure, the document pressing cover 12 of the image processing apparatus of the present invention does not need to have the belt 22 and the carrier shaft 23 shown in FIG. Figure 2
1 is a sectional view of the image reading apparatus of the present invention shown in FIG. 1 taken along a plane orthogonal to the sub-scanning direction.

In the figure, 28 is a pinion provided on the rotating shaft of the motor 27, and by engaging with the rack 25,
A device for converting the rotating operation of the motor 20 into a reciprocating operation on the rack 25, 29 are two guides projecting on the upper surface of the self-propelled transmission unit 26, and by the sandwiching structure with the pinion 28, The slider 30 holds the mesh with the rack 25, and four sliders 30 are provided at both ends of the lower surface of the self-propelled transmission unit 26 to enable the smooth movement of the self-propelled transmission unit 26. .

Reference numeral 31 is a slide plate formed at both ends of the diffusion plate 13, which is formed in the sub-scanning direction and serves as a slide surface of the slider 30, and 32 is a rotation fulcrum provided in the housing 10. , 33 serves as a rotation axis of the document pressing cover 12, 33 is an elliptical hole provided in the document pressing cover 12, and realizes the opening / closing operation of the document pressing cover 12 by inserting the rotation fulcrum 32. . here,
The reason why the elliptical hole 33 is formed in an elliptic shape instead of a circular shape is to provide a play so that the original table 11 and the diffusion plate 13 can reliably sandwich the original.

In this way, the self-propelled transmission unit 26
As shown in FIG. 3, the transmission light source 20, a motor 27 having a pinion 28 that meshes with the rack 25 as a rotating shaft, a slider 30 for sliding a slide plate 31,
The guide 29 holds the pinion 28 and the rack 25 in mesh with each other.

A self-propelled transmission unit 26 having this structure
Can be integrally manufactured by using a molding material such as resin. When such a manufacturing method is adopted, the socket of the transmissive light source 20 can be integrally formed, or the socket of FIG. As shown in FIG. 7, if the reflector 34 for converging the light emitted from the transmissive light source 20 is also integrally formed, the number of parts can be further reduced.

Next, the operation processing of the image reading apparatus of the present invention having such a configuration will be described. In the image reading apparatus of the present invention configured as above, the reflection original is placed on the original table 1.
1 is mounted, the reflection light source 16 is turned on, the motor 17 moves the optical unit 14 in the sub-scanning direction at a constant speed, and in response to this movement processing, the line image sensor 15 causes the reflection light source 16 to move. The image information of the illuminated reflection original is read.

On the other hand, when the transparent original is placed on the original table 11, the transparent light source 20 is turned on, the motor 17 moves the optical unit 14 in the sub-scanning direction at a constant speed, and in synchronization with this movement. By driving the motor 27,
The self-propelled transmission unit 26 moves in the sub scanning direction at the same speed as the optical unit 14 while using the rack 25 as a guide rail.

That is, by driving the motor 27,
The pinion 28 of the motor 27 receives pressure from the guide 29 and moves in the sub-scanning direction while using the rack 25 as a guide rail. According to this moving process, the self-propelled transmission unit 26 slides on the slider 30. It moves in the sub-scanning direction.

According to this moving process, the transmitted light source 20 is
Since it moves in the sub-scanning direction while facing the optical unit 14, the line image sensor 15 processes so as to read the image information of the transparent original illuminated by the transparent light source 20.

In this way, according to the present invention, it is possible to realize the reading of a transparent original without providing a belt or a carrier shaft for moving the transparent light source 20 inside the original pressing cover 12 as in the prior art. Like

FIG. 5 shows another embodiment of the image reading apparatus having the present invention. In this embodiment, the printed circuit board 35 is used as a base, and the motor 27 and the transmissive light source 20 are directly attached to the printed circuit board 35 to provide a configuration of the self-propelled transmissive unit 26 that realizes simplification of wiring. There is.

In order to realize this structure, since the opaque printed circuit board 35 is arranged on the upper surface side of the document pressing cover 12, the rack 25 is provided on the diffusion plate 13. become. In this example,
The socket 36 of the transmitted light source 20 is used as the slider 30 on one side, and a stopper 37 provided to define the position of the printed circuit board 35 on the upper surface of the rack 25 is provided.
It is used as the slider 30 on the other side.

Although the illustrated embodiment has been described, the present invention is not limited to this. For example, the embodiment shown in FIG. 1 discloses a configuration in which the rack 25 is provided at the approximate center position of the document pressing cover 12 in order to reduce the load on the motor 27, but the present invention is not limited to this. Absent. Further, in the embodiment, the present invention is disclosed according to the image reading apparatus that reads both the transparent original and the reflective original, but the present invention is not limited to this, and the image reading apparatus that reads only the transparent original. May be.

[0031]

As described above, according to the present invention,
When the transparent document placed on the document table is read by using the line image sensor, the transparent document can be read according to a smaller number of components than the conventional one.

[Brief description of drawings]

FIG. 1 is an example of the present invention.

FIG. 2 is an example of the present invention.

FIG. 3 is an example of a self-propelled transmission unit.

FIG. 4 is an example of a self-propelled transmission unit.

FIG. 5 is another embodiment of the self-propelled transmission unit.

FIG. 6 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 10 Case 11 Document Plate 12 Document Holding Cover 13 Diffuser 14 Optical Unit 15 Line Image Sensor 16 Reflected Light Source 17 Motor 18 Belt 19 Carrier Axis 20 Transmitted Light Source 25 Rack 26 Self-propelled Transmittable Unit 27 Motor

Claims (5)

[Claims] 1. A transparent manuscript table provided on a top surface of a housing for placing a manuscript to be read, and inside the housing,
An optical unit including a line image sensor for reading a document placed on the document table, a transmission light source provided with a diffusion plate on a surface contacting the document table, and irradiating the document table with light through the diffusion plate. And a document lid body
An image reading apparatus having a configuration in which a transparent original to be read is read by moving the optical unit and the transmissive light source while facing each other and moving in a direction orthogonal to a scanning direction of a line image sensor. In addition, the unit for mounting the transmission light source is configured to include a rack extending in a direction orthogonal to the scanning direction of the line image sensor, and a motor having a pinion that meshes with the rack is arranged.
A slider member that enables smooth movement inside the document cover, and a guide member that holds the engagement between the pinion and the rack by a sandwiching structure with the pinion, Characteristic image reading device. 2. The image reading device according to claim 1, wherein the rack is configured to be provided at a substantially central position of an inner upper surface of the document lid. 3. The image reading apparatus according to claim 1, wherein the rack is provided on the diffusion plate of the document cover. 4. The image reading device according to claim 1, 2 or 3, wherein the unit for mounting the transmissive light source is made of a molding material, and the slider member and the guide member are integrally formed, and the unit is provided with: A socket for a transmitted light source,
An image reading apparatus characterized in that the reflector for converging the light emitted from the transmissive light source is formed integrally with the reflector. 5. The image reading apparatus according to claim 1, 2, or 3, wherein the unit for mounting the transmissive light source is formed of a printed circuit board as a base.