JP2001341874A - Document carrier sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a document carrier sheet capable of preventing the failure in conveying in reading a document, and the production of a moire image, and having superior document exchanging characteristic. SOLUTION: In a typical constitution of this document carrier sheet 1, a transparent sheet 2 for covering a reading face of a document, and a base sheet 3 for covering a non-reading face of the document are connected at their one ends, the non-document face 2a or a document face 2b of the transparent sheet 2 is coarsened with microscopic irregularity.

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, and more particularly to a document carrier sheet for nipping and conveying a sheet-shaped document in an image reading apparatus having an automatic document feeder.

[0002]

2. Description of the Related Art In recent years, demand for image reading apparatuses for inputting images has been increasing. There are a wide variety of image reading devices, such as a flatbed type having a document table and capable of reading a sheet-shaped document or a thick book, and a film reading device that reads image information directly from photographic film. . In recent years, as the number of times of image input using these image reading devices has increased, the demand for an automatic document feeder that automatically feeds a sheet-shaped document has been increasing.

As an image reading apparatus provided with an automatic document feeder, there are a sheet feed type image reading apparatus which automatically conveys a sheet-shaped document and reads the image information thereof, and an automatic document feeder. There is a flat bed type image reading apparatus with an automatic document feeder detachably mounted on the flat bed type image reading apparatus.

In an image reading apparatus having such an automatic document feeder, a method using a document carrier sheet has been put to practical use so that the document is not damaged, or when the document is small or irregular in shape and there is a restriction on conveyance. Have been.

FIG. 7 shows a typical conventional document carrier sheet.
Indicates 100. Cover the reading surface side of the document P with the transparent sheet 101,
The non-reading side of the document P is covered with a pedestal sheet 102 having the same shape as the transparent sheet 101. And said and transparent sheet 101
The pedestal sheet 102 is joined to the pedestal sheet 102 at a joint 103 by an adhesive or welding. When the document is conveyed by the automatic document feeder of the image reading device, the document carrier sheet 100 is fed from the joining portion 103 side, and an image reading sensor (not shown) is pressed against the conveyance roller via the document carrier sheet 100 to be conveyed. While reading the image on the original P through the transparent sheet 101.

[0006]

However, when the original carrier sheet 100 is conveyed, the non-original surface of the transparent sheet 101
101a is transparent, that is, smooth, and the glass surface of the document reading sensor abutting on it is also transparent, that is, smooth, so that these are attracted more than necessary during document transport,
In some cases, transport failure occurred.

Further, since the non-document surface 101a, the document surface 101b, and the glass surface of the document reading sensor are all transparent and smooth surfaces, there is a problem that a moire image is generated between them.

In order to solve the above problem, the non-document side 10
1a so that it does not stick to the glass surface of the original reading sensor
It is conceivable to reduce the force of pressing the document reading sensor against the document carrier sheet 100. However, in the image reading apparatus having the above-described configuration, the conveyance force itself is reduced, and thus, there is a possibility that the conveyance performance of another sheet-shaped document may be deteriorated.

Further, the development reading sensor may be a document carrier sheet.
It is also conceivable that the pressing force of the image reading sensor is reduced while securing the conveying force of the document by providing the conveying rollers before and after the developing reading sensor without pressing the pressing roller 100.
However, this configuration increases the size of the apparatus and increases the production cost.

In addition, when the transparent sheet 101 and the document P are nipped and conveyed, the document surface 101b is attracted to the document surface, and the document P is damaged when the document P is separated from the document surface 101b. was there.

Furthermore, since the transparent sheet 101 and the pedestal sheet 102 have the same shape, it is difficult to separate these sheets when exchanging the original sandwiched between the original carrier sheets 100, and the original exchangeability is poor. was there.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a document carrier sheet which is excellent in document exchangeability while avoiding conveyance failure and occurrence of moire images when reading a document.

[0013]

In order to solve the above-mentioned problems, a typical configuration of a document carrier sheet according to the present invention includes a transparent sheet covering a reading surface of a document and a pedestal covering a non-reading surface of the document. In a document carrier sheet comprising a sheet and the transparent sheet and the pedestal sheet joined at one end, the non-document side of the transparent sheet is roughened by fine irregularities.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] An embodiment of a document carrier sheet according to the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a document carrier sheet, FIG. 2 is a cross-sectional view of the document carrier sheet, FIG.
FIG. 4 is an enlarged sectional view of the image reading unit.

(Image Reading Apparatus) First, the configuration of an image reading apparatus provided with an automatic document feeder and most effective for using the document carrier sheet according to the present invention will be described with reference to FIG. The image reading apparatus 10 shown in FIG.
The originals P stacked on the sheet P are separated and fed one by one by the feed roller 12 and the separation pad 13. A document detection flag 14 that rotates in contact with the document P and a document detection sensor 15 that detects the movement of the document detection flag 14 are provided on the downstream side of the feed roller 12. And rotates to the position shown by the solid line in FIG.
Changes from the light-shielded state to the light-transmitted state, and the leading edge of the sheet can be known.

On the sheet conveyance path, an image reading sensor 16 and a conveyance roller 18 are arranged opposite to each other with the image reading sensor 16 interposed therebetween.
The image reading sensor 16 is provided with a pressure spring 17 for pressing the image reading sensor 16 against the transport roller 18. Accordingly, the document P is read while being nipped and conveyed by the glass surface 16a of the image reading sensor 16 and the conveying roller 18.

When the document detection sensor 15 detects the leading edge of the sheet, a control board (not shown) issues a reading start command to the image reading sensor 16 after a certain period of time, and starts reading image information on the document P from an optimum position. When the trailing end of the document P passes the document detection flag 14, the document detection flag 14 rotates to the position indicated by the two-dot chain line in FIG.
Changes from the light-transmitting state to the light-shielding state, and the trailing edge of the sheet can be known. The control board issues an image reading end command to the image reading sensor 16 after a certain period of time has elapsed after detecting the trailing edge of the sheet, and ends the image reading. Thereafter, the document P is transported by the transport rollers 18 and is discharged out of the apparatus as it is.

(Document Carrier Sheet) Next, the document carrier sheet according to the present embodiment will be described. The document carrier sheet 1 shown in FIG. 1 includes a transparent sheet 2 covering the reading surface side of the document P and a pedestal sheet 3 covering the non-reading surface side of the document P, and one end thereof is joined at a joining portion 4. The joints are joined by an adhesive or welding, as in the conventional example. When the document is conveyed by the image reading device 10, the document carrier sheet 1 is fed from the joining portion 4, and the image on the document P is read through the transparent sheet 2 by the image reading sensor 16.

As shown in FIG. 2, the surface of the image reading sensor 16 which is in contact with the glass surface 16a, that is, the non-document surface 2a of the transparent sheet 2 has been subjected to a roughening process comprising fine random irregularities. It is translucent. The material of the transparent sheet 2 is polyester, but a transparent and durable resin sheet, for example, vinyl chloride or acrylic may be used. There are various processing methods for roughening the non-document surface 2a, such as melting using an organic solvent.

The material of the pedestal sheet 3 itself does not need transparency, so that paper or the like may be used in addition to the resin sheet such as polyester used for the transparent sheet 2. Joint 4
In general, ultrasonic welding is used when joining resin sheets, and an adhesive is used when joining the resin sheet and paper. However, a joining method using another member may be used.

Referring to FIG. 4, a state in which the original document carrier sheet 1 having the above configuration is conveyed by the image reading apparatus 10 and image information is read will be described. When the original carrier sheet 1 is conveyed, the non-original surface 2a of the transparent sheet 2 has been subjected to the roughening process, so that the non-original surface 2a of the transparent sheet 2 and the glass surface 16a of the image reading sensor 16 There is no suction due to the pressing force of the pressing spring 17. Further, since the frictional force due to the rubbing is reduced, the resistance in the transport direction acting between the transport roller 18 and the pedestal sheet 3 can be sufficiently reduced. As a result, the conveyance performance of the document carrier sheet 1 can be sufficiently ensured.

When reading an image, the image reading sensor 16
The light emitted from the light emitting element 16b and the light reflected from the document P are scattered by minute irregularities formed on the surface of the non-document surface 2a. Due to this light diffusion phenomenon, interference of light entering the light receiving element 16c can be suppressed. That is, the non-document surface 2a of the transparent sheet 2 and the glass surface of the image reading sensor 16
It is possible to suppress the generation of the moiré image generated in 16a.

As described above, according to the configuration of the original carrier sheet 1 according to the present embodiment, the roughening process consisting of fine and random irregularities is formed on the non-original surface 2a of the transparent sheet 2 of the original carrier sheet 1. By doing so, it is possible to suppress the occurrence of moiré images generated on the glass surface 16a of the image reading sensor 16 and the non-document surface 2a, and to improve the conveyance performance of the document carrier sheet 1.

[Second Embodiment] Next, a second embodiment of the document carrier sheet according to the present invention will be described with reference to FIG. FIG. 5 is a cross-sectional view of the document carrier sheet according to the present embodiment. The same reference numerals are given to the same portions as those in the first embodiment, and the description is omitted.

In the first embodiment, the transparent sheet 2
Although only the non-document surface 2a is subjected to the surface roughening process, in the document carrier sheet 5 according to the present embodiment, the document surface 2b of the transparent sheet 2 is also subjected to the roughening process including fine random irregularities. I am giving.

Thus, even when the document carrier sheet 5 sandwiching the document P is sandwiched between the image reading sensor 16 and the transport roller 18, the transparent sheet 2 and the document P can be prevented from being attracted. . Therefore, even when the original P is replaced, the original P is not damaged, and the original carrier sheet 5 excellent in original exchangeability can be provided.

Further, a light emitting element in the image reading sensor 16
The light emitted from the original 16b and the light reflected from the document P are transmitted through the transparent sheet 2.
Are scattered by fine irregularities formed on the original surface 2b. Due to this light diffusion phenomenon, interference of light entering the light receiving element 16c can be suppressed. That is, it is possible to suppress the occurrence of the moire image generated between the original surface 2b of the transparent sheet 2 and the original P.

As described above, according to the configuration of the original carrier sheet 5 according to the present embodiment, the original surface 2b of the transparent sheet 2 is also subjected to the surface roughening process, thereby achieving the effects described in the first embodiment. In addition to suppressing the occurrence of moiré images generated on the original surface 2b of the transparent sheet 2 and the original P,
Adhesion between the document surface 2b and the document P can be prevented to improve document exchangeability.

[Third Embodiment] Next, a third embodiment of the document carrier sheet according to the present invention will be described with reference to FIG. FIG. 6 is a perspective view of the document carrier sheet according to the present embodiment, and the same reference numerals are given to the same parts as those in the first embodiment, and the description will be omitted.

In the first embodiment, the transparent sheet 2 of the original carrier sheet 6 and the pedestal sheet 3 are formed in the same shape (see FIG. 1). However, in the present embodiment, the notches 7 are provided at both corners of the pedestal sheet 3 opposite to the joint 4. Thereby, the original carrier sheet 6
When exchanging the document P held between the transparent sheet 2 and the pedestal sheet 3, it becomes easy to separate the transparent sheet 2 and the pedestal sheet 3 at the notch 7, so that the exchangeability of the document P can be improved.

The notch 7 may be provided in at least one place, and its position is not limited as long as it is a position other than the joint 4. Further, a notch may be provided in the transparent sheet 2. Instead of the notch, for example, only one of the outer dimensions of the transparent sheet 2 and the pedestal sheet 3 may be shortened.

As described above, according to the configuration of the original carrier sheet 6 according to the present embodiment, the transparent sheet 2 and the pedestal sheet 3 are different from each other in outer shape, so that the transparent sheet 2 and the pedestal sheet 3 are separated from each other. Since the separation can be easily performed, the document exchangeability can be further improved in addition to the effects described in the second embodiment.

[0033]

As described above, according to the configuration of the original carrier sheet according to the present embodiment, the non-original surface of the transparent sheet of the original carrier sheet is subjected to a roughening process including fine random irregularities. Accordingly, it is possible to suppress the occurrence of the moire image generated on the glass surface of the image reading sensor and the non-document surface 2a, and to improve the conveyance performance of the document carrier sheet.

By subjecting the original surface of the transparent sheet to a roughening process, it is possible to suppress the occurrence of moire images generated between the original surface of the transparent sheet and the original, and to prevent the original surface from adhering to the original. Exchangeability can be improved.

Further, since the transparent sheet and the pedestal sheet have different outer shapes, the transparent sheet and the pedestal sheet can be easily separated from each other, so that the document exchangeability can be further improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a document carrier sheet.

FIG. 2 is a cross-sectional view of a document carrier sheet.

FIG. 3 is a configuration diagram of an image reading apparatus.

FIG. 4 is an enlarged sectional view of an image reading unit.

FIG. 5 is a cross-sectional view of a document carrier sheet according to a second embodiment.

FIG. 6 is a sectional view of a document carrier sheet according to a third embodiment.

FIG. 7 is a diagram illustrating a conventional representative document carrier sheet.

[Explanation of symbols]

 P 1 original 1 original carrier sheet 2 transparent sheet 2a non-original surface 2b original surface 3 pedestal sheet 4 joint 5 original carrier sheet 6 original carrier sheet 7 notch 10 image reading device 11 Feed tray 12… Feed roller 13… Separation pad 14… Document detection flag 15… Document detection sensor 16… Image reading sensor 16a… Glass surface 16b… Light emitting element 16c… Light receiving element 17… Pressure spring 18… Transport roller

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Joe Tsurumi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masahide Tagami 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (72) Inventor Yoshihisa Ibaraki 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term (reference) 2H012 CD01 2H076 BB00 3F101 LA01 LB02 3F343 FA03 FB02 JD02 5C062 AB36 AD02 AD03 BA00

Claims (3)

[Claims] 1. A document carrier sheet comprising: a transparent sheet covering a reading surface of a document; and a pedestal sheet covering a non-reading surface of the document, wherein the transparent sheet and the pedestal sheet are joined at one end. An original carrier sheet, wherein a non-original surface is roughened by fine irregularities. 2. A document carrier sheet comprising: a transparent sheet covering a reading surface of a document; and a pedestal sheet covering a non-reading surface of the document, wherein the transparent sheet and the pedestal sheet are joined at one end. An original carrier sheet, wherein an original surface is roughened by fine irregularities. 3. A document carrier sheet comprising: a transparent sheet covering a reading surface of a document; and a pedestal sheet covering a non-reading surface of the document, wherein the transparent sheet and the pedestal sheet are joined at one end. An original carrier sheet wherein the outer shapes of the pedestal sheets are different from each other.