JPS6331263A - Picture reader - Google Patents

Abstract

PURPOSE:To prevent flapping of an original document due to its floating on a reading line by linearly contacting an original feed guide with a platen in the vicinity of the reading line with respect to the direction of feeding the original document. CONSTITUTION:When the original document 6 is inserted from the direction shown by an arrow, it is held between a roller 4 and the original feed guide 30 at the position of the first contact line 31A with the counterclock rotation of the platen roller 4 and a carrying force is applied. Thereafter, the original document 6 passing the reading line 7 is held again between the roller 4 and the original feed guide 30 from both the directions at the position of the second contact line 31B and the original document is provided continuously with a carrying force corresponding to the previously applied carrying force. In such a way, since the original document 6 is held to a state in which it is brought into contacted with the platen roller 4 in the vicinity of the reading line 7, the flapping of the original document at the reading position is eliminated but stable picture information can be obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an image reading device, and more specifically, the invention relates to an image reading device that is disposed along a document feeding means such as a facsimile machine, and reads image information from the document surface. The present invention relates to an image reading device having a contact type optical sensor array for reading.

(Prior Art) FIG. 6 shows an example of the configuration of a conventional image reading device of this type, where 1 is an image reading sensor (hereinafter referred to as an image sensor). The image sensor 1 is configured to come into pressure contact with a document feed guide 3 or a platen roller 4 attached to its housing 2 through contact line 5, and the document 6 or document feed guide 3 to be read is placed at the position of the contact line 5. and the platen roller 4, and the platen roller 4
The document is fed by rotating counterclockwise.

Reference numeral 7 indicates a reading line that is read from the top of the document 6 being fed, 8 indicates a light source array in which light emitting sources such as light emitting diodes and EDs are arranged in a row, and 9 indicates a converging optical transmitter, such as a SELFOC lens. array (hereinafter referred to as SLA),
Reference numeral 10 denotes a photosensor array consisting of a row of light-receiving elements, and the light from the light source row 8 is reflected from the paper surface of the document 6 at the reading line 7, and is transmitted to the photosensor array 10 through the SLA 9 and transparent glass 11. As the focused light is received, image information is read out one after another.

In the case of such document feeding, the conveying force of the document 6 is generated by the contact line 5 between the roller 4 and the document feed guide 3, but for example, as shown in FIG. After passing through the contact line 5, the full conveyance force no longer acts on the document 6. Therefore, when multiple originals are being fed one after another, the leading edge 6' of the later-feeding original 6'
When the document A reaches the reading line 7, the trailing edge 6B of the previous document 6 will remain in the state shown in the figure, and the leading edge 6 of the document 6 that is being fed later will be stuck.
'A' gets under the trailing edge 6B of the preceding document 6.

However, when reading is performed in this J: connected state, the trailing edge 6B of the preceding original fA6 is read out, even though the leading edge 6'A of the backward-feeding original 6' should originally be read out. .

In order to prevent this from happening, it is sufficient to provide means for conveying the document on the left side of the reading line 7 in FIG. 6, but for example, as shown in FIG. In this case, the width of the entire document reading device in the conveyance direction is required, which makes the document reading device more bulky and becomes an obstacle to making it more compact.

[Problem that the invention seeks to solve]

The purpose of the present invention is to focus on the above-mentioned problems, and to solve the problems, the present invention is compact, and even when a plurality of originals are fed one after another, accurate reading of each original is guaranteed. An object of the present invention is to provide an image reading device that uses the following methods.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a housing in which a columnar light source and a photosensor array are arranged at predetermined positions, and a housing in which a columnar light source and a photosensor array are arranged in opposing positions of the housing. A document feeding kite that makes line contact with the platen and contributes to feeding the document while holding the document in line contact, and directs the light emitted from the column light source to the position of the reading line of the document. In the image reading device, the document feeding guide 1 is brought into line contact with the platen at a front and back position near the reading line with respect to the direction of document feeding. It is characterized by what it did.

[For production]

According to the image reading device of the present invention, the original guided to the image reading sensor is held between the original feeding guide and the platen at the contact line in front of the reading line, and the original is fed by the platen, and the original is fed by the platen. Since the document is again held between the document feed guide and the platen at the second contact line beyond the first and second contact lines, a conveying force is applied to the document at both the first and second contact lines. , the document can be held at the reading line position one after the other, without the problems of the conventional method.
Reading can be performed.

(Example) Hereinafter, an example of the wooden invention will be described in detail and specifically based on the drawings.

FIG. 1 shows an embodiment of the invention. In the following, parts having the same functions will be designated by the same reference numerals (t) and their explanations will be omitted. A first contact line 3 is formed into a mold and smoothly protrudes downward at two places.
1A and a second contact line 31B. Further, a cutout window 32 is bored between these contact lines 31A and 31B so as to match the waveform thereof, and in this example, 1. A reading line 7 is set near the center line of the window 32, that is, near the apex of the platen roller 4, which is between the first contact line 31A and the second contact line 31B. Note that FIG. 2 shows an example of the document feed guide 30, and in order to form the entire document as one piece, both ends of the window portion 32 are provided with ears 30A and 30J:
30B are left to match the shape of the waveform, and are formed by, for example, metal hammering, but it is preferable to use elastic 4.1-year-old 4 as shown in the example described later.

In this image reading device configured as J:
is inserted from the direction of the arrow, as the platen roller 4 rotates counterclockwise, the roller 4 and document feed guide 30
It is held at the position of the first contact line 31A, and a conveying force is applied. After that, the original 6 that has passed through the reading line 7 is again held at the second contact line 31B by the roller 4 and the original feeding guide I. The document is continuously fed with a conveyance force commensurate with the force.

As described above, since the original 6 is held in contact with the platen roller 4 before and after the reading line 7, there is no movement of the original at the reading position, and the reading line 7 is 5LA by setting it on the top of the platen roller 4.
9, it is possible to obtain stable image information, and furthermore, it is possible to prevent unauthorized reading as previously explained with reference to FIG.

Further, as explained in the example of FIG. 8, there is no need to separately provide a pair of rollers on the downstream side of the reading line, and the entire reading device can be made into a compact structure.

Now, in this example, the document feed guide 30 is configured as shown in FIG. The overall length of the document feed guide 30 in this direction is not shown in the figure, since it is necessary to maintain the necessary dimensions and also to leave gaps of n and m in the ears 30A and 30B, respectively, for integration. It becomes M as follows.

Therefore, in order to shorten the length M, it is best to use a document feeding kite 40 made of transparent resin such as methacrylic resin and without a window as shown in FIG. It is possible to shorten the length to the specified dimension N. However, in this case, as is clear from FIG. 1, the light is emitted from the light source array 8, is reflected from the surface of the document 6, and is received by the sensor array 10, or passes through the transparent document feed guide 40. So,
It goes without saying that it is necessary to take the refractive index at that time into consideration in order to obtain correct imaging.

FIG. 4 shows another practical example of the present invention. It is necessary for an image reading device to prevent out-of-focus caused by out of focus. must be maintained at the correct distance at all times.

Therefore, in this example, taking into consideration that the position of the contact line that presses against the document feed guide or platen roller and the reading line is generally misaligned, the above optical path length is calculated using the contact line of the rigid document feed guide as the base. Rather than setting, for example, the part 2A of the casing 2 of the image sensor 1 may be brought into contact with both ends 4A of the platen roller 4 as shown in this figure, or the roller bearing part 4B. , so that the set optical path length is maintained.

In this way, the maintenance of the optical path length is shared by the housing 2, while the document feeder guide I/30 may be constructed using, for example, a spring material, or may be constructed using a separate (tml!) material.
The roller 4 may be biased by one member, and the spring force thereof may be used to maintain contact with the platen roller 4 at the first contact line and the second contact line, which are like two continuous contact lines.

FIG. 5 shows yet another embodiment of the invention. In this example, the document feeding kite 50 is provided with rollers 51A and 51B, so that the rollers 51A and 51B can contact the platen roller 4 at 931A and 31B, respectively. Also in this example, in combination with the same configuration as the example in FIG.
It is desirable to have a spring edition. Note that the other configurations follow the example shown in FIG.

In the image reading device having the structure 17 as described above, since the friction between the contact lines 3+A and 318 with the document 6 is rolling friction, it is possible to reduce the load generated on these parts. It is possible to suppress the occurrence of scratches, jams, etc.

In the above description, the case where the document feeding guide is made of an integral material has been described. However, the present invention is not limited to this straight form, but is applicable to the case where the document feeding guide is formed from an integrated material. It goes without saying that a document feeder 1 to 1 that comes into contact with each other may be provided.

〔Effect of the invention〕

As explained above, according to the present invention, 1) Since the document feed guide or the document is held in pressure contact with the platen on both sides of the reading line, there is no possibility that the document will be loose due to lifting on the reading line. This has enabled highly accurate reading.

2) Furthermore, since the original is being fed in the above state,
When multiple originals are fed one after another, even after the trailing edge of the preceding original passes the reading line, it is held by the second contact and continues to feed the original. There are no obstacles to this.

3) With the above configuration, the original is biased toward the platen at two locations near the reading line by the original feeding guide provided in conjunction with the image sensor, so that the original is only fed. There is no need to increase the width or the length in the feeding direction, and a compact document reading device can be obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of the configuration of an image reading apparatus of the present invention, FIG. 2 is a perspective view of a document feeding guide thereof, and FIG. 3 is a perspective view of a document feeding guide according to another embodiment of the present invention. FIG. 4 is an explanatory diagram of another embodiment of the present invention, FIG. 5 is a schematic diagram partially showing the configuration of still another embodiment of the present invention, and FIG. 6 is an example of the configuration of a conventional image reading device. FIG. 7 is an explanatory diagram of a malfunction that occurs when multiple documents are read in the image reading device shown in FIG. 6. FIG. 8 is a schematic diagram showing an example of another conventional image reading device. It is a diagram. DESCRIPTION OF SYMBOLS 1... Image sensor, 2... Housing, 4... Platen roller, 7... Reading line, 8... Light source row, 9... SLA. 10... Optical sensor array, 30.40.50... Original feed guide, 31A, 31
B...Contact line, 32...Window section, 51A, 51B...Roller.

Claims (1)

[Claims] 1) A casing in which a columnar light source and a photosensor array are arranged at predetermined positions, a platen arranged at a position opposite to the casing,
a document feeding guide that is in line contact with the platen and contributes to feeding the document while holding the document in the line contact state; In the image reading device, the document feeding guide is brought into line contact with the platen at a front and back position near the reading line with respect to the direction of document feeding. An image reading device characterized by: 2) The image reading device according to claim 1, wherein the line contact is performed by a roller provided on the document feed guide.