JPH05188491A - Image reader - Google Patents

Abstract

PURPOSE:To easily make a change so as not to read the dirt and decoloration of a friction sheet and an ADF carrying belt, when a range wider than a document is read, or the document having high permeability, such as a tracing paper and a film, is read. CONSTITUTION:An auxiliary friction sheet 3 is attachably and detachably provided on a pressing plate 2 pressing the surface to be read, of a read document, separately from the installed friction sheet 5. When the range wider than the document is read, or the document having high permeability, such as the tracing paper, is read, in a state where the friction sheet 5 shows the dirt, the holding frame member 7 of the auxiliary friction sheet 3 is fixed on the pressing plate 2, and the friction sheet 5 is housed in the holding frame member 7. When the pressing plate 2 is lowered on a contact glass 9 on a copying machine main body 1, the reading surface of the pressing plate 2 is covered with the sheet 4 of the auxiliary friction sheet 3, and a stainless copied image can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a copying machine, a facsimile,
The present invention relates to an image reading device such as a scanner, and more particularly to an image reading device in which a friction sheet for pressing a document provided on a pressure plate is improved.

[0002]

2. Description of the Related Art A conventional image reading apparatus is provided with a friction sheet for holding an original on a pressure plate which presses a surface of the original to be read against a contact glass so as not to shift the original. ADF (Automatic Document Feeder)
In the case of the one provided with, the conveyor belt is made to be a friction sheet.

As the material of the friction sheet or the ADF conveying belt, a material such as polyester cloth coated with rubber such as polyurethane rubber coating is often used. For this reason, the back surface of the original document is likely to be stained with time, and the rubber itself is easily discolored due to deterioration. When scanning only the normal original area, in other words, when the original paper size and the reading area are the same or the reading area is smaller, dirt and discolored areas are hidden by the original, and the reading area on the back of the original or the contact glass is read. Although the outside position may be stained, it does not affect the read image.

[0004]

However, in the case of reading a wider area than the original, or in the case of a highly translucent original such as tracing paper or film, the above-mentioned stains and discoloration are read and the read information is recorded. When output, the recorded image becomes dirty.

In such a case, when the user carries out image reading by placing a large white paper on the document, a clear recorded image can be obtained. However, this method is troublesome and has a problem that the position of the document is likely to be displaced when a white paper is placed on the document. Further, the friction sheet is usually replaced as a dirty one. However, in general, the user has little knowledge of maintenance, and such a user cannot easily replace the friction sheet or the ADF transport belt. There is also a method of cleaning the friction sheet and the ADF transport belt with alcohol, but it is time-consuming, and the dirt is liable to remain without being completely cleaned, and replacement of the dirt sheet every time it becomes very expensive is very costly.

In view of such conventional problems, the present invention has been made
In addition, in consideration of less frequent reading of a wider area than the original or high translucency of the original, a means to replace the above-mentioned white paper placed on the original is provided, and the operation is easy. It is an object of the present invention to provide a document reading device that does not cause misalignment of the document.

[0007]

In order to achieve the above object, an image reading apparatus according to the present invention has a pressure plate which presses a surface to be read of a document to be read separately from an existing ADF conveyor belt or friction sheet. The auxiliary friction sheet that covers at least the effective reading range and holds the original document to be read is detachably provided.

In order to achieve the above-mentioned object, the image reading apparatus according to the present invention covers at least the effective reading range in addition to the installed ADF conveyor belt or friction sheet on the pressure plate that presses the surface to be read of the read document. It has a built-in friction sheet to hold the scanned document,
The built-in friction sheet is attached by pulling back and pushing the base end edge into the pressure plate and attaching a support member to the other end edge drawn outward from the slit provided in the pressure plate. The friction sheet can be fixedly held on the pressure plate in a state of covering at least the effective reading range.

In the image reading apparatus according to the present invention, a control unit for detecting the mounting of the auxiliary friction sheet on the pressure plate or the pulling-out of the built-in friction sheet, and a control for controlling a detection signal output from the detection unit. A unit may be provided, and the ADF may be controlled so as not to operate when the attachment of the auxiliary friction sheet or the withdrawal of the built-in friction sheet is detected.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. It should be noted that, in the following, the same parts as those in the prior art will be denoted by the same reference numerals, and overlapping description will be omitted.

1 and 2 show an embodiment of the present invention. FIGS. 1A and 1B are partial side views showing a copying machine as an image reading apparatus according to the present invention, and FIG. 2 shows the copying machine of FIG. It is a perspective view of an auxiliary friction sheet attached to a pressure plate. 1 in the figure
Is a copying machine main body, 2 is a pressure plate, and 3 is an auxiliary friction sheet. The pressure plate 2 is a contact glass 4 on the main body 1 of the copying machine.
A friction sheet 5 for pressing the original is provided so as to slightly project from the lower surface.

This embodiment relates to a removable friction sheet, in which the auxiliary friction sheet 3 holds the sheet 6 with a holding frame member 7. Since the sheet 6 needs some flexibility, a thin metal sheet or a plastic sheet (film) is used as a substrate, and a self-lubricating resin is used as a binder for surface treatment.
It is coated with a lubricating paint containing a lubricating additive and can be easily cleaned. Of course, it is also possible to adopt the conventionally used rubber material. Since it does not have rigidity by itself, as shown in FIG.
Hold around.

The holding frame member 7 has an inner size capable of accommodating the friction sheet 5 of the pressure plate 2, and has a pair of projecting mounting portions 8 at its longitudinal ends for mounting the pressure plate 2. It has a mounting portion 9 for sheet metal. See also FIG.
As shown in A and B, the pressure plate 2 is provided with a notch-shaped mounting portion 10 and a magnet 11.

When the friction sheet 5 is conspicuously soiled and a wider area than the original is read or a highly transparent original such as tracing paper is read, the pressure plate 2 is moved upward as shown in FIG. 1A. In the lifted state, the mounting portion 8 is fitted into the mounting portion 10 of the pressure plate 2 to fix one of the holding frame members 7, and the mounting portion 9 is attracted to the magnet 11 to fix the other. At this time, the friction sheet 5 of the pressure plate 2 is housed in the holding frame member 7. The pressure plate 2 is attached to the main body 1 of the copying machine.
When the contact glass 4 is placed on the upper contact glass 4 (FIG. 1B), the reading surface of the contact glass 4 is covered with the sheet 6 to obtain a copy image without contamination.

FIG. 5 shows a second embodiment of the present invention, FIG. 3 is a perspective view showing the outline of a copying machine as an image reading apparatus according to the present invention, and FIG. 4 is a state in which an auxiliary friction sheet is pulled out. FIG. 5 is a partial perspective view of the pressure plate shown in FIG. In the figure, 20 is a copying machine main body, 21 is a pressure plate, and 22
Is an ADF tray, 23 is an ADF transport belt, 24 is a cassette tray, 25 is an operation panel portion, 26 is an ADF transport belt drive shaft, and 27 is a pressure plate support shaft.

As shown in FIG. 5, a friction sheet (hereinafter referred to as built-in friction sheet) 2 built in the pressure plate 21.
In the reference numeral 8, a sheet 29 having the same structure as that of the previous embodiment is provided with one end of the sheet 29 through a slit 30 provided in the pressure plate 21 to the outside, and a supporting rod 31 is attached thereto. The other end of the sheet 29 is
It is connected to the wire 33 of the pullback mechanism section 32 and is always urged to pull back into the pressure plate 21. Therefore, unless the operator pulls out the sheet 29 by hand, the support rod 3
1 is housed in a recess 34 provided around the slit 30 so as not to project to the lower surface side of the pressure plate 21.
The pressure plate 21 has a recess 36 at a position where the pulled-out sheet 29 covers at least the reading surface of the contact glass 35 of the copying machine body 20, and both ends of the support rod 31 are hooked at positions near both ends of the recess 36. A protrusion 37 for holding is provided.

That is, when the ADF transport belt 23 is contaminated and the wider area than the original is read or the highly transparent original such as tracing paper is read, the pressure plate 21 as shown in FIG. The support rod 31 is taken out from the concave portion 34 in a state of being lifted up, the sheet 29 is pulled out from the pressure plate 21 by pulling as it is, and the sheet is set by hooking and setting the support rod 31 on the projection 37 of the concave portion 36. .. ADF conveyor belt 2
3 is covered with a sheet 29, and when the pressure plate 21 is lowered onto the contact glass 35, the reading surface of the contact glass 35 is covered with the sheet 29, and a copy image free from dirt can be obtained.

By releasing the support rod 31 from the projection 37 of the recess 36, the sheet 29 is pulled back into the pressure plate 21 by the pullback mechanism section 32. It should be noted that the wire need not be used as long as the sheet 29 itself can be rolled up and stored.

Reference numeral 38 in FIG. 5 denotes a friction sheet mounting detection switch, which is provided in the vicinity of the slit 30 in the pressure plate 21 and is turned on or off when the built-in friction sheet 28 is attached or detached.
It is set to N and OFF.

FIG. 6 is an operation flowchart of the copying machine based on the presence / absence detection of the built-in friction sheet 28. That is, if the ADF is operated with the built-in friction sheet pulled out, the ADF device, the ADF transport belt 23, the contact glass 35, the document, and the like may be damaged, and this can be prevented in advance. The detection flow is started with the power source of the copying machine main body 20 turned on. In step 1, the mounting detection switch 38 detects whether or not the built-in friction sheet 28 is pulled out, and if the built-in friction sheet 28 is not pulled out. If detected, it is determined in step 2 whether or not there is a document on the ADF tray 22, and if there is a document, the document is conveyed from the ADF tray 22 (step 3), the image is read (step 4), and the document is ejected. (Step 5), the normal control of returning to step 2 is performed.

On the other hand, if it is determined in step 2 that there is no document on the ADF tray 22, the process proceeds to step 6 to determine whether there is a document on the reading surface of the contact glass 35, and if there is a document, an image is read ( If step 7) is not present, then step 6 is bypassed and the operation of the apparatus is terminated.

When it is detected in step 1 that the built-in friction sheet 28 is pulled out, the ADF device does not operate even if a document is set on the ADF tray 22, and the process proceeds to step 6 to read the contact glass 35. It is determined whether or not there is a document on the surface, and if there is a document, the image is read (step 7), and if there is no document, step 6 is bypassed and the operation of the apparatus ends.

[0023]

According to the image reading apparatus of the present invention, since the auxiliary friction sheet is detachably attached to the pressure plate, the auxiliary friction sheet can be easily attached when necessary, and the position of the original does not shift. There is an effect that a good read image can be obtained even if the existing friction sheet or ADF transport belt is dirty. Further, since it is separate from the main body of the reading device, it can be purchased as needed, and there is an effect that the facility cost of the user does not rise unnecessarily.

In the image reading device of the second aspect, since the friction sheet is built in the pressure plate and has the pullback mechanism, the image reading device can be easily attached when necessary as in the device of the first aspect, and the position of the document can be changed. Without slipping,
Even if the existing friction sheet or ADF transport belt is dirty, it is possible to obtain a good read image and it is possible to easily store the image.

The image reading apparatus according to the third aspect of the invention has an effect that the ADF apparatus, the friction sheet, the contact glass, and the original are not damaged by operating with the friction sheet attached.

[Brief description of drawings]

FIG. 1 is a partial side view showing a copying machine as an image reading apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view of an auxiliary friction sheet attached to a pressure plate of the copying machine of FIG.

FIG. 3 is a partial side view showing a copying machine as an image reading apparatus according to a second embodiment of the present invention.

FIG. 4 is a partial perspective view showing a state in which an auxiliary friction sheet is pulled out in the embodiment of FIG.

5 is a sectional view of the pressure plate of FIG.

6 is an operation flowchart of the copying machine based on detection of the presence / absence of a built-in friction sheet in the embodiment of FIG.

[Explanation of symbols]

 1, 20 Copy machine main body 2, 21 Pressure plate 3 Auxiliary friction sheet 4, 35 Contact glass 5 Friction sheet 6 Sheet 7 Holding frame material 23 ADF transport belt 28 Built-in friction sheet 29 Sheet 30 Slit 31 Support rod 32 Pullback mechanism section 38 Attachment detection switch

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical indication H04N 1/00 D 7046-5C 1/10 7205-5C

Claims (3)

[Claims] 1. A pressure plate for pressing a surface to be read of a document to be read is detachably provided with an auxiliary friction sheet that covers at least the effective reading range and holds the document to be read, in addition to the installed ADF conveyor belt or the friction sheet. An image reading device characterized by the above. 2. A pressure plate that presses the surface to be read of the read document, in addition to the installed ADF conveyor belt or friction sheet, has a built-in friction sheet that covers at least the effective reading range and holds the read document.
The built-in friction sheet is attached by pulling back and pushing the base end edge into the pressure plate and attaching a support member to the other end edge drawn outward from the slit provided in the pressure plate. An image reading apparatus, wherein the friction sheet can be fixedly held on the pressure plate in a state of covering at least an effective reading range. 3. An auxiliary friction sheet, comprising: a detection unit for detecting attachment of the auxiliary friction sheet to the pressure plate or pulling out of the built-in friction sheet; and a control unit for controlling a detection signal output from the detection unit. 3. The image reading apparatus according to claim 1, wherein the ADF is controlled so as not to operate when the mounting of the built-in friction sheet or the pull-out of the built-in friction sheet is detected.