JPH03210871A - reading device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a reading device such as a facsimile machine using a contact type sensor with a shallow depth of field.

<Prior art> In general, relatively small reading devices such as facsimiles are unitized and can be miniaturized, and maintenance and handling are easy. Contact type sensors are often used instead of equipped with optical systems consisting of:

However, with a contact type image sensor that does not have a Selfox lens array, the depth of field is ±0. In+
It is shallow, about m, and reading outside this range is difficult. Therefore, in a reading device using a complete contact type image sensor, it is necessary to bring the surface of the document into close contact with the contact type image sensor. For example, a device shown in FIG. 4 is known.

FIG. 4 shows a facsimile machine as a reading device, and its document reading section A includes a document guide section 102 that guides the side portion of a document 101, and an ADF roller 103.
a and the pressing piece 10 pressed by the ADF roller 103a.
3b and sent from the document guide section 102.
01 one by one, and a pair of paper feed rollers 105a, 105a, which feeds the document 101 separated by the ADF section 103 to a complete contact type image sensor 104.
05b, and a CS roller 106 that brings the document 101 conveyed by the paper feed roller part 105 into close contact with the reading position 104a of the complete contact type image sensor 104 so that it does not come up from the reading position 104a. There is.

In the document reading section A, the document 1 is placed on the document guide section 102.
01 and starts the reading operation, the ADF roller 103a, paper feed roller section 105, and CS roller 106 are rotated by a drive motor (not shown).First, the ADF roller 103a separates the documents one by one, and then the paper feed roller The document 101 separated by the portion 105 is fed to the complete contact type image sensor 104, and the document 101 is separated by the CS roller 106.
01 to the reading position 104a and press the document 1 in close contact with the reading position 104a.
While conveying the original 101, the image information of the original 101 is read by the contact image sensor 104, and the original 1 after reading is conveyed.
01 is discharged out of the apparatus from a paper discharge section 108 by a paper discharge roller 107.

During the reading operation, the leading edge of the original 101 is at the reading position 1.
Before reaching 04a, the surface of the CS roller 106 is read by the fully contact image sensor 104, and the read data serves as the reference color when reading the original.
The roller surface is white.

Further, the CS roller 106 brings the original 101 into close contact with the reading position 104a of the full contact type image sensor 104, and therefore the full contact type image sensor 10
4. A cylindrical roller made of rubber material is used so that the original 101 can be brought into close contact with the document 101 regardless of the unevenness of the surface (see FIG. 5).

Further, the surface of the CS roller 106 is provided with minute irregularities. That is, the completely contact type sensor 104
When there is no original 101 between the CS roller 106 and the CS roller 106 (before and after reading the original 101), the CS
Since the rubber material on the surface of the roller 106 is in direct contact with the glass surface of the fully contact image sensor 104, frictional resistance is large and the load on the drive motor becomes large.
In some cases, synchronization may occur, so to prevent this, the surface of the CS roller 106 is provided with minute irregularities to prevent the surface of the CS roller 106 from touching the glass of the fully contact image sensor 104. This reduces the load on the drive motor.

<Problem to be Solved by the Invention> However, since there are minute irregularities on the surface of the CS roller 106, when the surface is read and used as reference color data when reading a document, the data contains the influence of the irregularities. This has the disadvantage that image information cannot be read with high accuracy.

The present invention has been made to solve the problems of the prior art described above, and its purpose is to provide a reading system that can read image information with high accuracy without the influence of unevenness appearing on reference color data when reading a document. The purpose is to provide equipment.

<Means for Solving the Problems> Means of the present invention for solving the problems described above includes a conveyance means for conveying a document, and a reading means for reading image information of the document conveyed by the conveyance means in close contact with each other. , a close contact means for bringing the document into close contact with a predetermined reading position of the reading means, and a close contact means for bringing the document into close contact with a predetermined reading position of the reading means, and the close contact means such that the circumferential surface of the close contact means read by the reading means is outside the range of the depth of focus of the reading means. It is characterized by the arrangement of means.

<Operation> In the above means, before the image information of the document is read by the reading means, the surface of the contact means is read and the read data is used as a reference color; It is out of the range of the depth of focus of the means and is read blurry, and even if minute irregularities are provided on the surface, the influence of the irregularities does not appear on the data of the reference color.

<Embodiment> Next, an embodiment in which the above means is applied to a facsimile machine will be described.

[First example]

1(a), (bl) and FIG. 2 show the first embodiment, FIG. 1(a) is an explanatory sectional view explaining the arrangement of the contact means with respect to the reading means, and FIG. FIG. 2 is an explanatory cross-sectional view showing a state when image information is read, and FIG. 2 is an explanatory side view showing a partially cutaway facsimile apparatus.

First, the overall configuration of the device will be explained with reference to FIG. 2.
is the main body of the device, with the top cover 1a at one end (the second
It is slanted lower on the left side of the figure, and is compact overall.

A document reading section 2 is installed at one end of the main body 1 (left side in FIG. 2), and a document insertion slot 3 is provided in this document reading section 2.
A document guide 5 that is slidable in the width direction of the document 4 within the document insertion opening 3 is provided.

In addition, between the document conveying path of the document reading section 2, that is, the document insertion port 3 and the document discharge port 6 provided at the center of the upper inclined surface 1a of the apparatus main body 1, there is an ADF roller 7a and the ADF roller 7a. an ADF unit 7 which separates the originals 4 sent from the original guide 5 one by one by having a pressing piece 7b pressed by the original guide 5; and a pair of feeders which feed the originals 4 separated by the ADF unit 7. Paper feeding section 8 consisting of paper rollers 8a and 8b
, a contact type image sensor 9 as a reading means for reading the image information of the original document 4 conveyed from the paper feed section 8; A CS roller 10 serves as a contact means for conveying the original 4 while adhering it to the reading position 9a with a predetermined pressing force, and a pair of paper ejection rollers lla and llb ejects the original 4 after reading from the original ejection port 6. Paper discharge section 1
Equipped with 1st class.

The contact image sensor 9 is a fully contact image sensor that does not have a SELFOC lens array and has a very shallow depth of field, and transmits image information signals read from the document 4 to the recording section of another device in facsimile mode. Furthermore, in the case of copy mode, the information is configured to be transmitted to its own recording section 12 installed at the other end of the apparatus main body 1 (on the right side in FIG. 2).

Further, the CS roller IO is made of a white rubber material, and a drive motor serving as a drive source ( Microscopic irregularities are provided to reduce the load on the surface (not shown).

Next, the contact type image sensor 9 of the CS roller 10
The arrangement relationship will be explained in detail with reference to FIG. 1(a).

The circumferential surface of the CS roller 10 is provided with minute irregularities. Before reading the document 4, the surface is read by a contact image sensor 9. If this read data is used as reference color data, this reference color data is The effect of unevenness appears.

Therefore, as shown in FIG. 1(a), the CS roller 10
Among the busbars constituting the circumferential surface of the contact image sensor 9
The CS roller 10 is arranged such that the generatrix 10a, which is in almost line contact with the glass surface 9b, is separated by a distance from the reading line 9a of the contact image sensor 9.

In other words, the reading line 9 of the contact type image sensor 9
The CS roller 10 is moved so that the circumferential surface of the CS roller 10 comes into contact with a distance @b away from a in the document transport direction.
0 is placed.

Here, the distance Mb is set such that the circumferential surface 10b of the CS roller 10 located on the reading line 9a is located outside the range of the focal depth a of the contact image sensor 9,
This varies depending on the depth of focus a, the diameter (curvature) of the CS roller 10, etc. In this embodiment, for example, if the outer diameter of the CS roller 10 is 16 mm and the depth of focus a of the contact image sensor 9 is 0.1, then the distance is set to 1.3 seconds.

Therefore, when reading the circumferential surface 10b of the CS roller 10 before reading the original 4 and using this read data as reference color data, the circumferential surface 10b is outside the depth of field,
The image is read blurry and the effects of unevenness are eliminated.
This is equivalent to obtaining reference color data using a CS roller without any unevenness.

When reading manuscript 4, as shown in Fig. 1, etc.),
When the document 4 enters between the circumferential surface of the CS roller 10 and the glass surface 9b of the contact image sensor 9, the circumferential surface of the CS roller 10 is elastically deformed, and its restoring elastic force deforms the document 4. is brought into close contact with the glass surface 9b, and the image information surface of the document 4 is positioned within the depth of focus of the contact type image sensor 9.

Note that C in FIG. 1(b) indicates the thickness of the document 4.

Next, the operation of the above embodiment will be explained.

When a document 4 is set on the document guide 5 and a reading start signal is input using an operation switch (not shown), a drive motor (not shown) operates to move the ADF roller 7a, paper feed roller 8a, paper ejection roller 11a, and CS roller 10, respectively. The ADF section 7 separates the documents 4 one by one and conveys them to the paper feed section 8 .

Next, a DES sensor (not shown) (document leading edge detection sensor)
When the leading edge of the document 4 is detected, the drive motor is stopped, and the rotation of the ADF roller 7a, paper feed roller 8a, paper ejection roller 11a, and CS roller 10 is temporarily stopped.

Then, after a predetermined period of time has elapsed, the drive motor operates again to rotate the ADF roller 7a, paper feed roller 8a, paper discharge roller 11a, and CS roller 10, respectively. A
After the rotation of the DF roller 7a etc., until the leading edge of the document 4 is conveyed to the reading position 9a of the contact type image sensor 9,
The contact image sensor 9 reads the circumferential surface 10b of the CS roller IO a plurality of times. At this time, as mentioned above, the peripheral surface 1
Since 0b is outside the focal depth a of the contact image sensor 9 and is read blurry, reference color data can be obtained with high accuracy even though there are minute irregularities on the circumferential surface of the CS roller 10.

Next, when the leading edge of the original 4 is conveyed to the reading position 9a of the contact type image sensor 9, the image information of the original 4 is read. At this time, the original 4 is pressed against the contact image sensor 9 by the CS roller 10, and the image information surface of the original 4 is within the depth of field (depth of focus a), so that image information can be read with high accuracy.

When the reading of the original 4 is completed in this way, the original 4 is ejected by the CS roller 10 which also plays the role of transporting the original, and then the original 4 is ejected from the original ejection port 6 by the ejection rollers 11a and llb. Ru.

This completes the reading of the image information for one sheet of the original 4.

After this, if there is a document 4 in the document guide 5, the same operation is repeated again.

[Second example]

In the first embodiment described above, the CS roller 10 is arranged at a distance from the reading line 9a of the contact image sensor 9 in the document transport direction, but the present invention is not limited thereto.

For example, as shown in the second embodiment shown in FIGS. 3(a) and 3(b), the central axis of the CS roller 10 is positioned directly above the reading line 9a of the contact image sensor 9, A similar effect can be obtained even if the contact image sensor 9 is placed so as to float above the glass surface 9b of the contact image sensor 9. Note that in FIG. 3(a), parts that are the same as those shown in FIGS. 1(a), (b) are designated by the same reference numerals, and their explanations will be omitted.

In this second embodiment, the distance d from the central axis of the CS roller 10 to the glass surface 9b of the contact type image sensor 9 is set as follows.

a+r<d<a+r+c Here, r is the radius of the CS roller 10.

Even in this case, the surface of the CS roller 1O is outside the depth of field (depth of focus a) of the contact image sensor 9, and when reading this surface to use as reference color data, the surface of the CS roller 10 The influence of unevenness can be eliminated, and this is equivalent to obtaining reference color data using a CS roller 10 without unevenness.

When reading the image information of the document 4, as shown in FIG.
The depth of field is within the range of depth of field (depth of focus a), and image information can be read with high accuracy.

<Effects of the Invention> As described above, in the present invention, since the contact means is arranged so that the circumferential surface of the contact means read by the reading means is outside the range of the depth of focus of the reading means, the reference color data when reading the document is Image information can be read with high accuracy without the influence of unevenness.

[Brief explanation of drawings]

FIG. 1 (B) and FIG. 2 show a first embodiment of the present invention, and FIG. b) is an explanatory sectional view showing the state when image information is read, FIG. 2 is an explanatory side view with a part of the facsimile machine cut away, and FIGS. Embodiment 2 of the present invention is shown, and the same figure (the figure is an explanatory cross-sectional view explaining the arrangement of the contact means with respect to the reading means, O in the same figure) is an explanatory cross-sectional view showing the state when image information is read, FIG. 4 is a partially cutaway side view of the facsimile machine, and FIG. 5 is a perspective view of the CS roller. 1 is the main body of the apparatus, 2 is a document reading section, 3 is a document insertion slot, 4 is a document, 5 is a document guide, 6 is a document discharge port, 7 is a separation section,
8 is a paper feed unit, 9 is a reading means (contact type image sensor),
9a is the reading position (reading line), 9b is the glass surface, l
O is the contact means (CS roller), 10a and 10b are the circumferential surfaces, a is the length of the depth of focus, b is the offset distance, C is the thickness of the document, and d is read from the central axis of the contact means (CS roller) The distance r to the glass surface of the means is the radius of the close contact means (CS roller).

Claims (1)

[Scope of Claims] Conveying means for conveying a document; reading means for reading image information of the document conveyed by the conveying means in close contact; and close contact means for bringing the document in close contact with a predetermined reading position of the reading means. A reading device comprising: and the close contact means is arranged such that the circumferential surface of the close contact means read by the reading means is outside the range of the depth of focus of the reading means.