JP2003046722A - Image reader and imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it easy to clean the rubbish such as paper powder, etc., having gotten in between platen glass and a transparent scoop sheet. SOLUTION: This image reader is constituted such that it has a press member 21 opposed to a transparent film member 22 and regulating the motion of a manuscript, and it can retreat the above press member in the direction of parting from the above transparent film member. This has a film holding member for holding the above transparent film member capably of mounting and removal, and the above film holding member is attached capably of mounting and removal to the device body.

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 capable of reading an image of a stationary original and an image of a conveyed original, and an image reading apparatus using the same.

[0002]

2. Description of the Related Art Conventionally, an image reading apparatus used in an image forming apparatus such as a facsimile or a copying machine has two types of reading methods capable of reading not only sheet-like originals but also thick originals such as books. There is an image reading device that has.

For example, as shown in FIG. 7, the image reading apparatus disclosed in Japanese Patent Laid-Open No. 09-037020 is as follows.
When reading a thick original such as a book, the original is placed on the platen glass 51 and brought into close contact with the pressure plate 52. While the original is stationary, the reading unit 53 is scanned in the direction of arrow a to read the image. I am supposed to do it. Further, when reading a sheet-like document, while the reading unit 53 is stopped at the reading position as shown in the figure, the document is carried by the carrying unit 54 while being carried along the document path (direction of arrow b). Is supposed to do.

At the reading position, there is a transparent scooping sheet 55 which is a transparent film, one end of which is fixed to a holding plate 57 with an adhesive or the like, and the holding plate 57 is screwed to a main body frame including a platen glass 51. The other end of the transparent scooping sheet 55 rests on the first guide plate 58 fixed on the platen glass 51.

As shown in FIG. 7, the transparent rake sheet 55 is
The driving force of the back roller 56 when the pressure plate 52 is closed is reduced, and the back roller 56 is disposed at a position facing the back roller 56 with a minute interval so that dirt on the back surface of the document does not adhere to the back roller 56.

Further, when the pressure plate 52 is opened, the transparent scooping sheet 55 and the back roller 56 can be retracted in the direction of separating from each other. Therefore, when the document stays in the document transport path of the transport unit 54, The user can easily take out the document staying in the document transport path. Also, when paper dust or the like is accumulated on the upper surface of the transparent scooping sheet 55, or when the back roller 56 is dirty, the back roller 56 is similarly retracted from the transparent scooping sheet 55, so that the user can clean it. You can

[0007]

However, in the above-mentioned image reading apparatus, the transparent scooping sheet 55 is integrally fixed to the holding plate 57, and the holding plate 57 is screwed to the body frame, so that the platen glass 51 is provided. It is difficult to clean dust such as paper dust that has entered between the transparent scooping sheet 55 and the transparent scooping sheet 55. Further, there is a problem that the user cannot easily replace the transparent scooping sheet 55 if it is scratched or broken.

Further, in the structure of the image reading apparatus described above,
A space 60 is created between the reading position and the second guide plate 59 that delivers the document from the transport unit 54 to the transparent rake sheet 55. It has been conventionally known that if there is a space on the upstream side of the reading position, the reading start position may be displaced or the document may fluctuate during reading to cause a read image defect.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to improve the cleanability and replaceability of a transparent scooping sheet, and further to improve the reading start position deviation and the read image defect. Is to prevent.

[0010]

To achieve the above object, a typical structure of the present invention comprises a stationary document reading unit for reading an image of a stationary document and a conveyed document reading unit for reading an image of a conveyed document. And a reading means for reading the image of the original, a conveying means for conveying the original, and a transparent film member for guiding the conveyed original in the conveyed original reading unit, wherein the conveying means is An image reading apparatus having a pressing member that faces the transparent film member in a conveyed document reading unit and restricts movement of an original, and the pressing member can be retracted in a direction away from the transparent film member. A film holding member for detachably holding the transparent film member is provided, and the film holding member is detachably attached to the apparatus main body.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) An embodiment of an image reading apparatus to which the present invention is applied will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of the image forming apparatus, and FIG.
3 is a main cross-sectional view showing the automatic feeding / reading device, FIG. 3 is a perspective view of the image reading device seen from above, FIG. 4 is an upper perspective view of the image reading device with the pressure plate unit opened, and FIG. 5 is a transparent scoop sheet. And an upper perspective view and a lower perspective view of the sheet pressing member,
FIG. 6 is a view showing a method of attaching the transparent scooping sheet and the sheet pressing member.

First, the configuration and operation of the image forming apparatus will be described with reference to FIG. In the image forming apparatus, as shown in FIG. 1, when an image reading start signal is input, the photoconductor drum 31 as an image carrier is charged by the charging means 33 so as to have a predetermined potential. On the other hand, an image of the original placed on the platen glass 5 is read by the conveyed original reading unit 3 that reads the original while conveying the original, and an image signal is sent to the image forming unit for forming an image.

In the image forming section, an electrostatic latent image corresponding to the original image is formed on the photosensitive drum 31 by the exposing means 32 such as an LED or a laser which emits ON / OFF light upon receiving the image signal. . Next, this electrostatic latent image is developed by a developing device 34 as a developing means containing toner particles, and a toner image is obtained on the photosensitive drum 31.

In this way, the toner image formed on the photosensitive drum 31 is electrostatically transferred onto the transfer material by the transfer device 37. After that, the transfer material is electrostatically separated, and the fixing device 36
Then, the image is output after being fixed by heat.

On the other hand, on the surface of the photosensitive drum 31 after the toner image transfer, a cleaner 35 removes adhered contaminants such as transfer residual toner and, if necessary, image exposure optical memory (ghost).
Is repeatedly used for image formation by being exposed by the pre-exposure means 38 for removing the.

Next, the configuration and operation of the conveyed document reading unit 3 will be described with reference to FIGS. The conveyed document reading unit 3
The pressure plate unit 1 includes a conveyed document reading unit 3, and the reading unit 2 includes a platen glass 5 and a contact image sensor 24 as a reading unit.

As shown in FIGS. 3 and 4, a white background plate 6 is attached to the stationary original reading portion on the lower surface of the pressure plate unit 1 in order to bring the original into close contact with the platen glass during reading of the stationary original, and a hinge 7 is provided. The pressure plate unit 1 can be opened and closed around the center of rotation.

As shown in FIG. 2, the transported original reading unit 3 has a substantially U-shaped original transport path (hereinafter referred to as U turn path) 19 as a document guide surface.
Reference numeral 19 denotes a first roller pair as a conveying means for conveying the document S.
14 and the second conveying roller pair 15, a document edge sensor 20 for detecting the front end and the rear end of the document S, and the like are attached.

Further, on the upstream end side of the U-turn path 19, a document stopper 18 that regulates the leading end position of the document S stacked on the document placing tray 4, a document presence sensor 17 that detects the presence or absence of the document S, A pickup roller 11 that contacts the uppermost one of the stacked documents S and picks it up, and a separation roller 12 and a separation pad 13 that are pressed against each other for separating the document S picked up by the pickup roller 11 into one sheet. Is provided on the downstream end side of the U-turn path 19 for discharging the document S and the reading white background plate 23 as a pressing member for pressing the document S against the transparent scoop sheet 22 as the transparent film member on the platen glass 5. The document discharge roller pair 16 is provided.

Further, in the transported original reading unit 3, an original placing tray 4 is provided so as to be connected to the upstream end side of the U-turn path 19, and the original is discharged integrally with the upper surface of the pressure plate on the downstream side of the original discharging roller pair 16. A tray 26 (see FIG. 3) is formed.

The contact-type image sensor 24, which is arranged via the conveyed document reading section 3 and the platen glass 5, irradiates the image information surface of the document S with light from an LED array (not shown) as a light source, and the image information surface The reflected light reflected is focused on a sensor element by a SELFOC lens (not shown) to read image information.

The contact-type image sensor 24 moves to the left and right (in the direction of arrow a), and is read at the right side in the drawing when reading a stationary original, and is fixed at the position shown in FIG. 2 when being read by the conveyed original reading section 3. The configuration is such that an original that is conveyed is read.

In the transported original reading unit 3, when the operator places the original S on the original placing tray 4, the original S is set from the right side of the apparatus with the read image surface facing upward. At the time of setting the document, the front end position of the document S is regulated by the document stopper 18, and the presence or absence of the document S is detected by the document presence / absence sensor 17.

When the operator gives an instruction to start reading from an operation unit (not shown), the drive unit (not shown) rotates, the document stopper 18 is pushed down by the pickup arm 27, and the document S is picked up by the pickup roller 11 from the document stopper 18. It is sent into the inside of U-turn path 19 through the upper surface of.
At this time, in the transported original reading unit 3, the originals S are separated one by one by the separating roller 12 and the separating pad 13, and the uppermost original S is separated and conveyed.

Further, the separated original S is conveyed along the U-turn path 19 by the first conveying roller pair 14, and the original S is further conveyed by the second conveying roller pair 15 on the upper surface of the sheet pressing plate 21 as a film holding member. Read through the white background
It is conveyed between the 23 and the transparent scooping sheet 22.

In the conveyed document reading unit 3, the document edge sensor is used.
When the leading edge of the document S is detected by the document 20, the contact type image sensor 24 starts to read the image information when the document S is conveyed by a predetermined amount from that position. At that time, the manuscript S
Is pressed against the read white background plate 23 so that a read image defect due to floating of the document does not occur. After the reading is started, the document S is lifted up by the transparent scooping sheet 22 and the sheet guide plate 25, and moves toward the document discharge roller pair 16. And
When the trailing edge of the document S is detected by the document edge sensor 20, when the predetermined amount is conveyed from that position, the reading of the image information by the contact image sensor 24 is completed.
Then, the document S is conveyed by the document discharge roller pair 16 and discharged to the document discharge tray 26 integrally formed on the upper surface of the pressure plate.

In this way, in the document feeding / reading section 3,
The above-described reading operation is repeated until the document presence sensor 17 detects the absence of the document.

Next, the operation of the image reading apparatus will be described in detail with reference to FIG. A transparent plastic material such as polypropylene, polyester or PET is used for the transparent rake sheet 22. In this embodiment, the thickness is about 0.1 mm.
The polyester film is made of a material having a hard coating on the passage surface side, and is less likely to be scratched by friction with the original.

As shown in FIG. 5A, the sheet pressing plate 21
Has a guide surface 21a on its upper surface, and guide ribs 21b are formed on the guide surface 21a. The guide surface 21a and the guide rib 21b are designed on the substantially same surface as the document transport path so as to form the same document transport path as the U-turn path 19, and the document transported from the U-turn path 19 is not caught and is smoothly transparent. It can be guided onto the scooping sheet 22.

As shown in FIG. 5 (b), the transparent rake sheet 22 is locked by the sheet locking claw 21d of the sheet pressing plate 21,
It is possible to handle them together. In the locked state, the transparent scooping sheet 22 has the locking claws 21d of the sheet pressing plate 21.
Since it is sandwiched between the retaining wall 21e and the retaining wall 21e, it does not come off spontaneously, but the user can easily detach it by elastically deforming the transparent rake sheet 22.

As shown in FIG. 6, a lock claw 21c is formed on the sheet pressing plate 21, and when the sheet pressing plate 21 placed on the platen glass 5 is inserted in the direction of arrow c, it is provided on the scanner cover 28. The lock claw 21c is locked in the lock hole 28a, so that the sheet pressing plate 21 and the transparent scoop sheet can be easily
22 can be attached to the reading unit 2. Further, when removing the sheet pressing plate 21, the sheet pressing plate 21 can be easily pulled out in the opposite direction of the arrow c while pressing the lock claw 21c visible from the lock hole 28a with a pen tip or the like, so that the sheet pressing plate 21 and the transparent member can be easily removed. The scooping sheet 22 can be removed from the reading unit 2.

Therefore, even if dust such as paper dust generated by document transportation is accumulated between the transparent scooping sheet 22 and the platen glass 5, the user can remove the sheet pressing plate 21 and the transparent scooping sheet 22 to clean them. Can be done easily. Further, even when the transparent scooping sheet 22 is damaged or broken, the user can easily remove the transparent scooping sheet 22 from the sheet pressing plate 21 and replace it. Further, since the original document is conveyed on the sheet pressing plate 21 without interruption, it is possible to prevent the reading start position shift and the read image defect. (Other Embodiments) In the above-described embodiment, the configuration in which the reading white background plate 23 is pressed against the original document and the transparent scooping sheet 22 is illustrated, but the present invention is not limited to this, and for example, a rear roller similar to the conventional example is used. It may be.

Further, by providing a gap between the reading white background plate 23 or the back roller and the transparent rake sheet 22 to prevent scratches due to friction with the original, the transparent rake sheet 22 is inexpensive without hard coating. It can also be a material. This is effective because it can be easily replaced even if it is damaged.

Further, in the above-described embodiment, the copying machine is exemplified as the image forming apparatus to which the image reading apparatus is applied, but the image reading apparatus is not limited to this, and the image reading apparatus may be a reading system of an image forming apparatus such as a facsimile machine. You may use as.

[0035]

As described above, in the present invention, the film holding member detachably holds the transparent film member, and the film holding member is detachably attached to the apparatus main body. By disposing the film holding member, it is possible to improve the cleaning property and the exchangeability of the transparent film member, and the original is conveyed on the film holding member without delay, so that the reading start position shift or the read image defect occurs. Can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus.

FIG. 2 is a main cross-sectional view showing an automatic feeding / reading device.

FIG. 3 is a perspective view of the image reading apparatus as viewed from above.

FIG. 4 is an upper perspective view of the image reading apparatus with a pressure plate unit opened.

FIG. 5 is an upper perspective view and a lower perspective view of a transparent scooping sheet and a sheet pressing member.

FIG. 6 is a view showing a method of attaching a transparent scooping sheet and a sheet pressing member.

FIG. 7 is an explanatory diagram of a conventional image reading device.

[Explanation of symbols]

1 ... Pressure plate unit 2 ... Reading unit 3 ... Transported original reading unit 4 ... Original tray 5 ... Platen glass 6 ... White background 7 ... Hinge 11… Pickup roller 12… Separation roller 13… Separation pad 14 ... 1st conveying roller pair 15… Second transport roller pair 16 ... Document discharge roller pair 17… Document presence sensor 18 ... Document stopper 19… U Turn Pass 20… Document edge sensor 21… Seat retainer plate 21a ... Guide surface 21b ... Guide rib 21c ... Lock claw 21d ... Seat locking claw 21e… Prevention wall 22… Transparent scoop sheet 23 ... Read white background 24 ... Contact image sensor 25… Seat guide plate 26… Original output tray 27… Pickup arm 28… Scanner cover 28a ... Lock hole 31… Photosensitive drum 32 ... Exposure means 33 ... Charging means 34 ... Developer 35 ... Cleaner 36… Fixer 37… Transfer device 38… Pre-exposure means

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masakatsu Yamada             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Shigeyuki Sugiyama             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Yasushi Ishida             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Takuma Suzuki             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F-term (reference) 2H076 BA07 BA08 BA10 BA15 BA20                       BA24 BA47                 5B047 BA01 BA02 BB02 BC14 BC18                       CA09                 5C062 AA05 AB17 AB30 AB32 AD05                 5C072 AA01 BA13 LA07 NA01 XA00

Claims (6)

[Claims] 1. A stationary original reading unit for reading an image of a stationary original, and a conveyed original reading unit for reading an image of a conveyed original,
The reading unit has a reading unit for reading an image of the original document, a conveying unit for conveying the original document, and a transparent film member for guiding the conveyed original document in the conveyed original document reading unit. An image reading apparatus having a pressing member that faces the transparent film member and restricts movement of an original in a portion, and is configured to be retractable in a direction in which the pressing member is separated from the transparent film member, the transparent film member An image reading apparatus, comprising: a film holding member that detachably holds the film, the film holding member being detachably attached to the apparatus main body. 2. The image reading apparatus according to claim 1, wherein a pressure plate unit integrally having a conveying unit including the pressing member, the reading unit, the platen glass, the transparent film member, and the film holding unit. An image reading apparatus, comprising: a reading unit integrally having a member, wherein the pressure plate unit can be brought into contact with and separated from the reading unit. 3. The image reading apparatus according to claim 1, wherein at least a part of an upper surface of the film holding member has an original guide surface for guiding the conveyed original. Reader. 4. The image reading apparatus according to claim 3, wherein the document guide surface is substantially flush with a document transport path of the pressure plate unit. 5. A conveyance document reading unit that reads an image of a document conveyed in a document conveyance path, a reading unit that reads an image of the document, and a transparent film member that guides the document in the conveyance document reading unit. An image reading apparatus having, having a film holding member that detachably holds the transparent film member, wherein the film holding member conveys a document from the document conveyance path onto the transparent film member without delay, An image reading apparatus having a guide surface that is substantially the same as the original transport path, and detachably attached to the apparatus main body. 6. An image reading unit for reading an image of an original,
An image forming apparatus that forms an image based on an image signal read by the image reading unit, wherein the reading apparatus is the image reading apparatus according to claim 1. Forming equipment.