JP2002271569A - Image reader, facsimile equipment and image processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reader, with which an image defect produced by the inclination of an original or the like will not occur, without damaging the function of a guide for the original, even if a thick and flexible sheet is used for preventing the white level of a read blank from being lowered by transmitting the background in the case of reading, at a low cost. SOLUTION: As a representative configuration of the image reader for solving the problem, this device is provided with an original feeding means for feeding the original, a reading means for reading image information on the original to be fed by the original feeding means, a pressing member composed of a flexible sheet for pressing the original at the read position of the reading means and an energizing means for energizing the pressing member to the read means and the pressing member is equipped with comb-line notches on the upstream side of the read position.

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 for reading image information while conveying a document, and an image processing apparatus having the same, such as a facsimile apparatus.

[0002]

2. Description of the Related Art Conventionally, an image reading apparatus used in a facsimile apparatus or the like often adopts a configuration in which a contact image sensor is used to read an image while conveying a document. When such a contact type image sensor is used, a pressing member for pressing a conveyed document to the sensor is required.

[0003] For example, Japanese Patent Publication No. 7-90942 (conventional example 1)
7, a flexible sheet 301 is used as a pressing member for pressing an original on the image sensor 300, a reading reference sheet 302 is superimposed on the back surface of the flexible sheet 301, and these are weighted by a weight member 303. To the image sensor 300.

In Japanese Unexamined Patent Publication No. 6-37978 (conventional example 2), as shown in FIG. 8, a flexible sheet 305 is used as a pressing member for pressing an original to an image sensor 304,
A backing member 306 is placed on the back surface of the flexible sheet 305, and these are urged to the image sensor 304 by an urging member 307. The urging member 307 is composed of a plurality of sheets stacked with their tips shifted from each other.

[0005]

In recent years, there has been a demand for an image reading apparatus capable of reading and conveying various types of originals in order to reduce the size and speed of the apparatus. For this reason, satisfactory document transportability is satisfied, the white level serving as a white reference at the time of reading is high,
There is a need for a pressing member that realizes stable reading.

In addition, the depth of focus of the contact type image sensor becomes shallower with the improvement of the reading resolution, and the disturbance of the document conveyance is apt to affect the image. Is increasing.

However, when the pressing member strongly presses the document to the reading position of the sensor, a conveyance resistance occurs when the document is conveyed. For this reason, problems such as the document being skewed, the image being distorted, and the image being stretched or contracted are likely to occur.

On the other hand, when the thickness of the sheet of the pressing member is reduced so as not to cause a resistance when the document is conveyed, the background is transmitted at the time of reading, the white level of a read white background serving as a white reference for reading is reduced, and the black of the document is changed to black. , Or a white background of a document cannot be determined to be white, which tends to cause image defects.

In such a situation, in the conventional example 1, the thin flexible sheet 30 is used as a pressing member for the original.
1 is used, and the reading reference sheet 302 is superimposed on the back surface to prevent transmission of the background. However, there is a problem that the white reference is composed of two parts, the white level is unstable due to the variation at the time of assembling, the skew is liable to occur due to the conveyance resistance of the reading reference sheet 302 at the time of document conveyance, and image defects are likely to occur. Also, considering the assembly cost and parts cost for attaching the reading reference sheet, a flexible sheet that does not have a reading reference sheet, has good transportability of a document, and has a high white level as a white reference at the time of reading is stable. .

Also, in the above-mentioned conventional example 2, a thin flexible sheet 305 is used as a document pressing member, and a backing member 306 is stacked on the back surface. Therefore, as in the first conventional example, the white reference is composed of two parts, the white level is unstable due to variations during assembly, and
There is a problem that the skew is easily caused by the conveyance resistance of 306 and an image defect is easily generated. Further, since the urging member 307 is composed of a plurality of sheets stacked with their leading ends shifted from each other, the pressing force is determined by the elasticity of the plurality of sheets, and the proper urging force is maintained. There is a problem that is difficult.

Accordingly, the present invention provides a method of skewing a document without using a thick and strong sheet because the background does not penetrate during reading and the white level of a read white background does not decrease. It is an object of the present invention to provide at low cost an image reading apparatus which does not cause image defects due to.

[0012]

In order to solve the above-mentioned problems, a typical configuration of an image reading apparatus according to the present invention comprises a document conveying means for conveying a document, and a document conveying means for conveying the document conveyed by the document conveying means. Reading means for reading image information, a pressing member made of a flexible sheet for pressing the original to the reading position of the reading means, and urging means for urging the pressing member against the reading means; The member has a comb-shaped notch provided upstream of the reading position.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of an image reading apparatus, a facsimile apparatus and an image processing apparatus according to the present invention will be described. In the following description, a facsimile apparatus as an image processing apparatus having an image reading apparatus to which the present invention is applied will be described as an example.

(Image Processing Apparatus) First, the overall configuration of a facsimile apparatus as an image processing apparatus will be described with reference to the drawings. FIG. 4 is a schematic sectional view showing a schematic configuration of the facsimile machine, and FIG. 5 is an external perspective view of the facsimile machine. As shown in FIG. 4, the apparatus main body 101 includes a document S above a recording apparatus main body 104 composed of a laser beam printer.
And an image reading unit 103 for reading the image information. The control unit 121 disposed inside the apparatus includes a recording system control unit, a reading system control unit, and a communication system control unit.

As shown in FIG. 5, an original mounting table 102, a cartridge cover 114, and an ADF (auto document) are arranged at the top of the apparatus so that a plurality of originals S can be stacked on an upper cover of an apparatus main body 101. Feeder) cover 115, handset 122 for communication, operation unit 124,
A display unit 125 and a tally lamp 126 indicating an operation state of the facsimile apparatus are provided. Image reading unit 1 on the side of the device
03 document ejection tray 108, recording medium ejection tray 112 of the recording apparatus main body 104, and MP (multi-paper) cassette unit 113
It has. An upper cassette unit 111 and a lower cassette unit 127 for accommodating a recording medium are arranged below the apparatus, and a front cassette 119 that is detachable from the front of the apparatus is mounted on each of them.

(Recording Apparatus Main Body) As shown in FIG. 4, the recording apparatus main body 104 has an image forming section 110 at the center, and forms an image on a recording medium fed from the upper cassette section 111 or the MP cassette section 113. Then, the recording medium is discharged onto the recording medium discharge tray 112.

The laser scanner 109 emits a modulation signal from the oscillator 109a based on the image signal output from the control unit 121, scans the polygon mirror 109b, reflects the reflection mirror 109c, and scans the photosensitive drum 110a. Irradiate light.

In the image forming section 110, the photosensitive drum 110
a is integrated into the recording cartridge 110e together with the primary charger 110b, the developing sleeve 110c, and the cleaning blade 110d, and is configured to be detachable from the apparatus main body 101. The surface of the photosensitive drum 110a is uniformly charged by the primary charger 110b, and when the surface is irradiated with the scanning light, an electrostatic latent image is formed.
The image is visualized by the toner supplied from c. The recording cartridge 110e is attached to the cartridge cover 114 on the upper surface of the main body.
It can be attached and detached by opening and closing.

The recording medium P is fed from the upper cassette unit 111, the lower cassette unit 127, or the MP cassette unit 113. Although the lower cassette section 127 is omitted in FIG. 4, the configuration is substantially the same as that of the upper cassette section 111. The lower cassette unit 127 can be separated and combined as an option, and the number of recording media that can be stored in the entire apparatus can be changed.

Upper cassette section 111 and lower cassette section 127
The recording medium P is loaded and stored in a rotatable middle plate 119a inside the front cassette 119 mounted on the
It is biased upward by 19b. The recording medium P is sent out from the uppermost sheet by the pickup roller 118a,
The paper is fed by the feed roller 118b while being separated one by one by the separation claw 119c and the retard roller 118c. The separated recording medium P is fed to a cassette conveying roller pair 118.
It is conveyed by d and is sent to the conveying roller 128.

The recording medium P loaded on the MP cassette unit 113 is pressed against the MP separation roller 130a by the rotation of the intermediate plate 113a by the pressing member 113b. The recording medium P includes an MP separation roller 130a and an MP separation pad 130.
The sheets are separated and fed one by one by b, and sent to the transport roller 128.

The transport roller 128 is moved so that the leading end of the toner image on the photosensitive drum 110a and the leading end of the recording medium P coincide with each other.
The recording medium P is conveyed at an appropriate timing. When the toner image on the photosensitive drum 110a is transferred to the recording medium P by the transfer charger 110f, the recording medium P is conveyed along the conveyance guide 123, and after the toner image is fixed by the fixing unit 110g, the discharge roller The paper is discharged to the recording medium discharge tray 112 outside the apparatus by 110h.

A partitioning section 120 is provided above the recording apparatus main body 104 to separate the image reading section 103 from the recording apparatus main body 104. The partition unit 120 is a duct that opens to the rear side of the apparatus, and heat generated by the image forming unit 110 affects the image reading unit 103 by flowing an appropriate amount of air by a fan (not shown) arranged on the rear side. This prevents water vapor that has been applied or evaporated from the recording medium P from condensing and dripping onto the recording medium P.

(Facsimile Operation) Next, a control configuration of the facsimile apparatus will be described with reference to FIG. FIG. 6 is a block diagram of a control system of the facsimile machine. In the control system 200 shown in the figure, a control unit 121 that controls the entire facsimile apparatus includes an MPU, a ROM that stores a control program of the MPU, and a RAM used as a work area for various data processing and a temporary storage unit for image information. , And an image processing unit that performs image scaling, resolution conversion, and the like.

The control section 121 is provided with a calendar, a clock function, and the like having a known configuration. An area in the RAM for storing important system setting information such as one-touch key destination information and software switch information is powered by a battery backup. You are protected from accidental obstacles. The protected RAM area is an EEPROM
(Including a flash memory).

The control system 200 includes the control unit 121 described above and an operation unit
Each component such as 124, display unit 125, reading control unit 202, recording control unit 203, and communication control unit 204 is connected through an interface.

The operation unit 124 includes various key switches such as a numeric keypad, a function key, a one-touch key, a start key, and a stop key. The display unit 125 includes an LCD for displaying various messages, various LEDs for displaying a transmission mode and the like, and a tally lamp for notifying a distant operator of a communication state or occurrence of a failure.

The reading control unit 202 includes a driving unit such as a reading motor, a contact image sensor 1, an image processing unit for shading and binarizing a read image, various sensors for detecting a document, and the like. The recording control unit 203 includes a driving unit such as a recording motor, a recording unit that controls the laser scanner 109 and the image forming unit 110, an image processing unit that performs smoothing of an image to be recorded, various sensors that detect a recording medium, and the like. Consists of

The communication control unit 204 performs outgoing calls, incoming calls, encoding of image data, and the like. Also, MODEM, N
It has communication equipment such as CU, communication network 205, handset 1
22 is connected.

The CPU external interface 206 includes the control unit 1
An interface for directly transmitting and receiving data from the device 21. By connecting to an external computer via a line such as RS232C, SCSI, LAN, or the like, the device can be used as a scanner or printer of the external computer. The hard disk 207 is used as a large-capacity nonvolatile memory for storing image information and the like.

(Image Reading Unit) Next, the image reading unit 103 will be described with reference to FIG. 6, FIG. 1 and FIG. FIG. 1 is a cross-sectional view illustrating a main part of the image reading unit, and FIG. 2 is a plan view illustrating a main part of the image reading unit. The image reading unit 103 includes a document mounting table 102, a document transport unit 105 (document transport unit), a contact image sensor 1 (reading unit), a document pressing unit 106, and a document discharge tray 108.

In FIG. 6, a slider 102a is provided on the original placing table 102 and is movable in a direction perpendicular to the conveying direction of the stacked originals, so that the width direction of the originals can be regulated and aligned. When the document S is a long document, by opening the auxiliary tray 102b, it is possible to prevent the trailing end of the document S from protruding from the document table 102 and hanging down.

The document S placed on the document table 102 is guided by the lower document guide 9 and the upper document guide 11. The preliminary transport roller 105b is rotated by the preliminary transport solenoid 105c, and the original is sent out by rotating while the original S is pressed against the preliminary transport pressing piece 105a.
The sheets are separated and fed one by one by the 5d and the retard roller 105e. Next, the feeding roller 105f is conveyed to the close contact type image sensor 1 by the feeding roller 105g pressed against the original, and a document pressing unit described later
At 106, the image information of the original S is read while the original S is pressed against and brought into close contact with the contact image sensor 1. And the original S
Is discharged to a document discharge tray 108 outside the apparatus by a discharge roller 105i pressed against a discharge roller 105h.

As shown in FIG. 1, the contact image sensor 1 irradiates light from the LED array 2 as a light source to the reading position 4 through the contact glass 3 and reflects the light on the image information surface of the original S on the reading position 4. The light is focused on the sensor element 6 via the lens 5 to read image information. The contact type image sensor 1 is fixed to a leader frame 8 by a mounting plate 7. An upper document guide 11 and a lower document guide 9 for guiding the document S are arranged on the upstream side of the contact type image sensor 1 in the transport direction, and the upper document guide is provided on the downstream side.
11 and a lower document guide 10 are arranged.

The document pressing section 106 presses a document against the contact image sensor 1. The document pressing unit 106 includes a reading white background 12 (pressing member) and a weight shaft 16 (biasing means) for urging the reading white background 12 against the contact type image sensor 1, and the reading white background 12 is a white background front guide made of a galvanized steel plate. 13 and a rear guide 14 on a white background, respectively, at an upstream bonding portion 12a and a downstream bonding portion 12b.

The reading white background 12 is a flexible white polyester film (thickness of about 110 to 500 μm) in this embodiment.
You are using However, the reading white background 12 is not limited to a polyester film as long as it is a flexible sheet material. Since the white reading background 12 is a white reference that determines the slice level of reading, in order to read various types of originals without causing image defects, the white level is high so that the background is not transmitted during reading, and a stable thick Is desirable.

The front white guide 13 is fixed to the upper document guide 11, and the rear white guide 14 is attached to the upper document guide 11 so as to be movable only in the vertical direction.
The weight shaft 16 is also mounted to be movable only in the up-down direction by a guide portion (not shown) of the upper document guide 11. Then, the conveyed document S is pressed against the contact glass 3 of the close contact type image sensor 1 from the non-reading surface side via the reading white background 12 by the weight of the weight shaft 16. As a result, the document S transported between the lower document guide 9 and the upper document guide 11 comes into close contact with the contact glass 3 and the image is read by the contact image sensor 1.

At this time, if the read white background 12 is thick and strong, the read white background 12 is strongly pressed against the contact glass 3 and a conveyance resistance occurs during document conveyance. Here, the bending strength D of the read white background 12 is represented by D = bh ³ E / 12, where b is the width, h is the thickness, and E is the longitudinal elastic coefficient. Therefore, by changing the width and thickness of the read white background 12 as parameters, the strength of the waist of the read white background 12 can be adjusted.

Therefore, in this embodiment, as shown in FIG. 2, a plurality of comb-shaped notches 19 are provided on the white reading background 12 on the upstream side of the reading position 4. As a result, the apparent width of the read white background 12 can be reduced, and the waist strength on the upstream side of the read white background 12 (on the white background front guide 13 side) can be reduced. Accordingly, it is possible to prevent the reading white background 12 from strongly pressing the original S against the contact glass 3, and the conveyance resistance is not excessively increased.

The read white background 12 also serves as a guide for the document S up to the reading position 4. However, even if a comb-shaped notch 19 is provided on the upstream side of the read white background 12, the function as a guide for the document S can be obtained. There is no loss. That is, the read white background 12 according to the present embodiment can achieve both the guide of the document S and the function as a stable white reference with a high white level at the time of reading.

A CS discharging brush 18 for removing static electricity on the surface of the conveyed document S is disposed downstream of the contact type image sensor 1 in the conveying direction. Further, the front white guide 13, the white rear guide 14, and the neutralizing brush 18 are connected to the frame ground of the apparatus through a ground line (not shown) so that the removed static electricity does not accumulate.

Next, the notch 19 provided on the white reading background 12 will be described. The notch 19 is formed by press working before the reading white background 12 is bonded to another member. First, a double-sided tape serving as an adhesive is adhered to the adhesive portions 12a and 12b on the back surface of the read white background 12 with the release paper attached. In this state, the notch shape is punched out from the reading surface side to the non-reading surface side by press working. When processed in this manner, a notch-shaped hole is also punched out in the double-sided tape, so that after the release paper is removed, no adhesive remains in the notch 19 and no burrs are formed on the reading surface side by pressing. Further, as shown in FIG. 2, the downstream end 19a of the notch 19 is formed to be narrow, so that the front end of the document S is not caught.

As described above, even when the reading white background 12 having a high white level and a thick waist is used so that the background is not transmitted during reading, a comb-shaped notch is provided on the upstream side of the reading white background 12. With the provision, the stiffness of the white reading background 12 can be reduced, and the conveyance resistance can be reduced. In addition, since the function as a document guide is not impaired, both good document transportability and stable reading without image defects can be achieved at low cost.

[Second Embodiment] A second embodiment of the image reading apparatus, facsimile apparatus and image processing apparatus according to the present invention will be described. FIG. 3 is a plan view for explaining a main part of the image reading unit according to the present embodiment. The same reference numerals are given to the same parts as those in the first embodiment, and the description is omitted.

In the first embodiment, the read white background 12
A notch 19 is provided in the form of a comb on the upstream side of the reading position 4 of FIG. On the other hand, in the present embodiment, a plurality of holes 20 are provided on the upstream side of the white reading background 12, thereby reducing the waist on the upstream side of the white reading background 12 (on the front side of the white background guide 13).

In FIG. 3, the reading white background 12 is a flexible white polyester film (about 11 mm thick) as in the first embodiment.
0-500 μm) and is pressed against the contact glass 3 by the weight of the weight shaft 16. On the upstream side of the reading position 4 of the white reading background 12, a plurality of holes 20 extending in the document conveying direction are formed. The hole 20 is formed such that the downstream end 20a in the transport direction is narrow, so that the leading end of the document S is not caught.

As described above, a plurality of holes are provided upstream of the read white background 12.
The provision of 20 makes it possible to reduce the waist on the upstream side of the white reading background 12 and prevent the white reading background 12 from strongly pressing the original S against the contact glass 3. On the other hand, the portion corresponding to the reading position 4 has a thick reading white background 12, so that the light emitted from the LED array 2 does not transmit and the white reference does not become unstable.

With the above-described configuration, the waist on the upstream side of the read white background 12 can be weakened even when the thick white read white background 12 is used, as in the first embodiment. It is possible to achieve both good document transportability and stable reading without image defects at low cost.

[0049]

As described above, by providing a comb-shaped notch or a hole extending in the document conveying direction on the upstream side of the reading position of the pressing member, the white level is prevented so that the background is not transmitted during reading. Therefore, even when a thick and high waist pressing member is used, the waist on the upstream side in the transport direction of the pressing member can be weakened, and the transport resistance can be reduced. Therefore, various types of originals can be read without causing image defects, and the function as a guide for the originals is not impaired, so that good original transportability and stable reading without image defects can be achieved. It can be compatible at the cost.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a main part of a first image reading unit.

FIG. 2 is a plan view illustrating a main part of a first image reading unit.

FIG. 3 is a plan view illustrating a main part of an image reading unit according to a second embodiment.

FIG. 4 is a schematic sectional view showing a schematic configuration of a facsimile apparatus.

FIG. 5 is an external perspective view of the facsimile machine.

FIG. 6 is a block diagram of a control system of the facsimile machine.

FIG. 7 is a main part configuration diagram of an image reading apparatus according to Conventional Example 1.

FIG. 8 is a main part configuration diagram of an image reading apparatus according to Conventional Example 2.

[Explanation of symbols]

 P: Recording medium S: Document 1: Contact image sensor 2: LED array 3: Contact glass 4: Reading position 5: Lens 6: Sensor element 7: Mounting plate 8: Leader frame 9: Lower document guide 10: Lower document guide 11… Upper document guide 12… Read white background 12 a… Adhesive part 12 b… Adhesive part 13… Front guide on white background 16… Rear guide 16… Weight shaft 18… Static elimination brush 19… Notch 19 a… Downstream end 20… Hole 20 a… Downstream end 101: Main body 102: Document mounting table 102a: Slider 102b: Auxiliary tray 103: Image reading unit 104: Image recording unit 105: Document conveying unit 105a: Preliminary conveying pressing piece 105b: Preliminary conveying roller 105c: Preliminary conveying solenoid 105d… feed roller 105e… retard roller 105f… feeding roller 105g… feeding roller 105h… discharging roller 105i… discharging roller 106… original pressing section 108… original Discharge tray 109 laser scanner 109a oscillator 109b polygon mirror 109c folding mirror 110 image forming unit 110a photosensitive drum 110b primary charger 110c developing sleeve 110d cleaning blade 110e recording cartridge 110f transfer charger 110g ... Fixing unit 110h ... Discharge roller 111 ... Upper cassette unit 112 ... Recording medium discharge tray 113 ... MP cassette unit 113a ... MP middle plate 113b ... Press-contact member 114 ... Cartridge cover 115 ... ADF cover 118a ... Pickup roller 118b ... Feed roller 118c ... Retard roller 118d… Cassette transport roller pair 119… Front cassette 119a… Middle plate 119b… Middle plate spring 119c… Separating claw 120… Partition part 121… Control part 122… Handset 123… Transfer guide 124… Operation part 125… Display part 126… Tally lamp 127… Lower cassette part 128… Feed rollers 130a ... MP separation roller 130b ... MP separating pad 200 ... control system 201 ... CPU 202 ... read control unit 203 ... recording control unit 204 ... communication control unit 204a ... connecting portion 205 ... communication network 206 ... CPU external interface 207 ... hard disk

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H072 AB08 CB06 JA04 JC07 2H076 BA07 BA47 5B047 AA01 BA01 BB02 BC01 BC14 BC18 5C062 AA02 AB17 AB32 AB33 AB38 AD06 BA01 5C072 AA01 EA07 NA01

Claims (5)

[Claims] 1. A document conveying means for conveying a document, reading means for reading image information of the document conveyed by the document conveying means, and a flexible sheet for pressing the document to a reading position of the reading means. An image reading apparatus comprising: a pressing member; and a biasing unit that biases the pressing member against the reading unit, wherein the pressing member has a comb-shaped notch provided upstream of the reading position. . 2. The image reading apparatus according to claim 1, wherein the pressing member has a hole extending in a document conveying direction instead of the notch. 3. The image reading apparatus according to claim 1, wherein the reading unit is a contact image sensor. 4. A facsimile apparatus comprising: the image reading apparatus according to claim 1; and an image communication unit that sends an image read by the image reading apparatus to a communication line. . 5. An image processing apparatus comprising: the image reading device according to claim 1; and an image forming unit that records an image read by the image reading device on a recording medium. apparatus.