JP2002262037A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reader that can accurately correct read data of image information and needs no frequent cleaning of a white reference body. SOLUTION: The image reader 1 is provided with a sensor unit 24 that emits a light to a document 6 carried along a carrying path 10 and receives a light reflected in the document to optically read image information and with the white reference rod body 31 having an outer surface 34 exposed onto the carrying path and a white face 36 at its part to correct the sensor unit to have an identical output to read the image information. The white reference body is placed on the carrying path in a way of turning around the axis over a 1st position at which the white face is exposed to the carrying path and a 2nd position at which the white face escapes under the carrying path in the case of reading image information. A cover 55 covering the white face is placed around the white reference body when the white reference body is turned to the 2nd turning 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 example, a character recognition apparatus) for optically reading an image (image) from a sheet-like record carrier such as a form, and more particularly to a color balance control for image information. The present invention relates to a structure for preventing contamination of a reference white reference body and adhesion of foreign matter to the reference white body.

[0002]

2. Description of the Related Art Conventionally, a reduced image sensor unit is disposed on a transport path on which a form is transported, and image information such as characters and figures recorded on the form is optically read and recognized via the sensor unit. A character recognition device (hereinafter, referred to as OCR) is known.

In a reduced image sensor unit, when a form reaches a reading position on a transport path, the form is irradiated with light from a fluorescent lamp, and the light reflected by the form includes a reflection mirror and a lens. It leads to a CCD image sensor via an optical system. For this reason, the image information of the form is input to the CCD image sensor as light density information, where it is converted into an electric signal and read.

Meanwhile, in the conventional OCR, in order to cope with fluctuations in the amount of light of a fluorescent lamp serving as a light source, color balance correction control is executed by a CCD image sensor to stabilize an image image.

More specifically, for example, Japanese Patent Application Laid-Open No. Hei 4-2089
As disclosed in Japanese Patent Application Laid-Open No. 35-291938 and Japanese Patent Application Laid-Open No. Hei 6-291938, a white reference plate serving as a reference for color balance control is arranged in a form conveyance path, and a white reference plate is read before reading image information of the form. By irradiating light from the fluorescent lamp to the surface of the CCD, the amount of white reflected light and RGB color balance
Measurement is performed by an image sensor, and based on the measurement, correction control of image data read data is performed.

The prior art white reference plate is provided so as to be movable between a first position at which it advances to a reading position on a transport path and a second position at which it retreats from the reading position. The white reference plate is moved to a first position prior to the start of reading of image information. At this first position, the surface of the white reference plate is irradiated with light from a fluorescent lamp, and the reflected light is emitted. , The CCD color balance correction control is executed so that the output of the CCD image sensor of all bits becomes all the same.

The white reference plate moves to the second position before the form reaches the reading position on the transport path, and retreats from the transport path. For this reason, at the time when the reading of the image information is started, the form and the surface of the white reference plate are kept in a non-contact state, and the reading of the image information and the color balance correction control are performed at the same position on the transport path. Despite the configuration, the white reference body can be prevented from being stained or damaged.

[0008]

According to the above prior art, during a period in which image information reading processing is being executed,
The white reference plate is held at a second position off the transport path. However, since the second position where the white reference plate is held is set below the conveyance path, the white reference body is conveyed along the conveyance path even when moved to the second position. Is in a state of facing a report that is

For this reason, if foreign matter such as paper dust, paper chips or dust adhered to the form is peeled off during transportation, the foreign matter may drop toward the white reference plate. Is more likely to adhere to the white reference plate and remain there.

In particular, as disclosed in Japanese Patent Application Laid-Open No. 6-291938, when a white reference plate keeps a substantially horizontal posture, it advances into a form transport path or conversely retreats from a transport path. The surface of this white reference plate always faces the form. Therefore, once the foreign matter adheres to the surface of the white reference body, the foreign matter becomes difficult to peel off from the white reference plate, and the surface of the white reference plate is stained at an early stage.

As a result, it is difficult to perform accurate color balance correction control based on white, causing problems such as reading errors and unstable read image information.

Further, in order to suppress the occurrence of reading errors, frequent cleaning work of the white reference plate is inevitable, and accordingly, maintenance work of the image reading apparatus is troublesome, and the burden on the operator is increased. Is increased.

The present invention has been made in view of such circumstances, and it is possible to reliably prevent the white surface of the white reference body from being stained, and to accurately correct read data of image information. An object of the present invention is to provide an image reading apparatus that does not require frequent cleaning of a white reference body.

[0014]

According to a first aspect of the present invention, there is provided an image reading apparatus, comprising: a transport path for transporting a sheet-shaped record carrier; and a transport path along the transport path. A sensor unit that irradiates the record carrier with light and receives reflected light from the record carrier to optically read image information recorded on the record carrier; and an outer surface exposed to the transport path. And a bar-shaped white reference body having a white surface for correcting data so that the output of the sensor unit that reads the image information is the same on a part of the outer surface.

The white reference body includes a first position where the white surface is exposed to the transport path and receives the light;
When reading the image information of the record carrier, the white surface is disposed on the transport path so as to be rotatable around an axis over a second position retreating below the transport path, and A cover for covering the white surface when the white reference body is rotated to the second rotation position is provided around the reference body.

According to such a configuration, when reading the image information of the record carrier, when the white reference body is rotated from the first position to the second position, the white surface of the white reference body is changed. Covered by cover. For this reason, the white surface does not need to be exposed to the outside below the transport path, and even if foreign matter such as dust attached to the record carrier falls during the transport, the foreign material may adhere to the white surface or may not adhere to the white surface. Less likely to remain. Therefore, accurate correction control of read data based on white can be performed, and good image information can be captured.

At the same time, since the white surface of the white reference body can be prevented from being stained for a long period of time, frequent cleaning of the white surface can be omitted, and the labor required for maintenance of the white reference body can be reduced. can do.

The portion of the outer surface of the white reference body that is exposed to the transport path when the white reference body is rotated to the second position is directed downward with respect to the transport path. If it is inclined, even if a foreign substance falls from the record carrier during the reading process of the image information, the foreign substance slides down along the inclined surface of the white reference body as it is, and does not remain on the black outer surface. .

Therefore, when reading the image information, the foreign matter is not erroneously recognized as the image information or the starting end of the record carrier, and the reading error of the image information and the transport error of the record carrier hardly occur.

In order to achieve the above object, an image reading apparatus according to the present invention according to a seventh aspect of the present invention comprises: a conveying path for conveying a sheet-shaped record carrier; By irradiating this record carrier with light and receiving reflected light from this record carrier,
A sensor unit for optically reading image information recorded on the record carrier, and a sensor having a black-processed circular outer surface exposed on the transport path and reading the image information on a part of the outer surface It has a flat white surface for correcting the output of the unit to be the same, and reads the first position where the white surface advances to the reading position on the transport path and the image information of the record carrier. At this time, a rod-shaped white reference body installed on the conveyance path so as to be rotatable around an axis over a second position where the white surface retreats below the conveyance path, and the white reference body is A driving means for selectively rotating the first reference position or the second position, and a cleaning member disposed around the white reference member and slidably in contact with the outer surface and the white surface when the white reference member rotates. And having It is characterized.

According to such a configuration, the white reference body is the first
When the cleaning member is rotated from the position to the second position or from the second position to the first position, the cleaning body slides on the outer surface or the white surface of the white reference body. Therefore, even if foreign matter such as dust falling from the storage carrier adheres to the outer surface or the white surface of the white reference body during transport of the record carrier, the foreign matter is forcibly applied by the cleaning body when the white reference body rotates. Is scraped off.

Accordingly, it is possible to accurately control the correction of the read data based on the white color, and at the time of reading the image information, the sensor unit does not mistakenly recognize the foreign matter as the image information or the start of the record carrier. Reading errors and transport errors of the record carrier hardly occur.

Further, it is possible to prevent the white reference member from being stained for a long period of time, and it becomes unnecessary to frequently clean the white reference member. Therefore, maintenance of the white reference body is facilitated, and the reading process can be performed efficiently.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 schematically shows the configuration of the OCR 1. The OCR 1 includes a box-shaped apparatus main body 2, and a hopper table 3 that can move up and down and first and second stacker tables 4 and 5 are arranged on the front surface of the apparatus main body 2.
The hopper table 3 is for accumulating a form 6 as a sheet-shaped record carrier, and image information such as characters, figures or symbols to be read and processed is recorded on at least the surface of the form 6.

The apparatus body 2 has a first guide plate 8 and a second guide plate 8.
And the guide plate 9 are supported. The first and second guide plates 8 and 9 are vertically opposed to each other,
A transport path 1 connecting the hopper table 3 and the first and second stacker tables 4 and 5 between the guide plates 8 and 9.
0 is configured.

The transport path 10 guides the forms 6 accumulated on the hopper table 3 to the first stacker table 4 or the second stacker table 5. The transport path 10 is a horizontal front half 10 connected to the hopper table 3.
a and the middle part 1 rising from the rear end of the first half part 10a
0b and a horizontal rear half 1 extending from the upper end of the intermediate part 10b toward the first and second stacker tables 4 and 5.
0c.

At the boundary between the hopper table 3 and the first half 10a of the transport path 10, a plurality of paper feed rollers 11a and 11b for sending out the forms 6 accumulated on the hopper table 3 one by one to the transport path 10 are arranged. ing. As shown in FIG. 2, the paper feed rollers 11a and 11b
a, 12b, a pair of side plates 13a, 1
3b and is located between the side plates 13a and 13b. The paper feed rollers 11a and 11b are
The motors 2a and 12b are interlocked with a motor (not shown), and are rotationally driven in synchronization with each other by power transmission from the motors.

In the transport path 10, a plurality of roller units 14a to 14l for transporting the form 6 are arranged at intervals. Roller units 14a-
141 includes a first drive roller 15 and a second drive roller 16, respectively. First and second drive rollers 1
5 and 16 are opposed to each other with the transport path 10 interposed therebetween, and the form 6 is guided between these drive rollers 15 and 16.

As shown in FIG. 2, each roller unit 14
a to 14l of the first and second drive rollers 15, 16
Are respectively connected to the side plates 13 of the apparatus main body 2 via the roller shafts 17.
a, 13b and is located between these side plates 13a, 13b. First and second drive rollers 15
Are linked to a motor (not shown) via a roller shaft 17, and are driven to rotate in synchronization with each other by power transmission from the motor.

For this reason, the form 6 is conveyed one by one from the starting end to the end of the conveying path 10 by sequentially straddling between the adjacent roller units 14.

As shown in FIG. 1, a first sensor 19 is arranged at the beginning of the transport path 10. The first sensor 19 optically detects whether or not the form 6 has been sent to the transport path 10 and transmits the next form 6 to the transport path 10.
It has a function to determine the timing of sending to the. At the end of the transport path 10, a gate 20 that sorts the transported form 6 to either the first stacker table 4 or the second stacker table 5, and the form 6 reaches the end of the transport path 10. Sometimes, a second sensor 21 that determines the operation timing of the gate 20 is provided.

As shown in FIG. 1 and FIG.
Is a reading position for reading image information from the form 6
Has P1. The reading position P1 is located on the first half 10a of the transport path 10 in the adjacent roller unit 14b.
And 14c. And the transport route 1
0, the first and second guide plates 8 and 9 have openings 23a and 23b at positions corresponding to the reading position P1, respectively.
These openings 23 a and 23 b are formed in a slit shape extending in the width direction of the form 6.

Above the reading position P1, a reduced imaging type sensor unit 24 is arranged. The sensor unit 24 is for optically reading image information on the surface of the form 6, and includes a light emitting unit 25, a pair of reflection mirrors 26 a and 26 b and a reduction lens 27 forming a reduction optical system.
And a CCD image sensor 28.

The light emitting section 25 has a pair of aperture type fluorescent lamps 29 as light sources. The fluorescent lamp 29 is located right above the opening 23a of the first guide plate 8, and faces the reading position P1 on the transport path 10 through this opening 23a. The light from the fluorescent lamp 29 irradiates the surface of the form 6 conveyed along the conveyance path 10 as shown by a dashed line in FIGS.
After being reflected upward by this surface, two reflecting mirrors 2
The light is guided to a CCD image sensor 28 via 6a and 26b and a reduction lens 27. Therefore, the image information on the surface of the form 6 becomes the light density information and becomes the CCD image sensor 2.
8, the light is converted into an electric signal, and is read optically. The fluorescent lamp 29 that illuminates the form 6 cannot avoid a decrease in illuminance and a change in light amount at low temperatures. Therefore, in the OCR 1, the CCD image sensor 28 that receives light density information executes color balance correction control. Therefore, at the reading position P1 on the transport path 10, a white reference body 31 serving as a reference for color balance control is disposed. As shown in FIG.
The white reference body 31 is constituted by a straight round bar 32 extending in the width direction of the form 6. The round bar 32 has both ends at the side plates 13a, 13b of the apparatus body 2 via bearings 33a, 33b.
13b so as to be rotatable, and faces the transport path 10 through the opening 23b of the second guide plate 9.

The round bar 32 has a circular outer surface 34. A part of the outer surface 34 forms a flat surface 34a, and the flat surface 34a extends linearly along the axial direction of the round bar 32. A white tape 35 is attached to the flat surface 34a. Tape 35 is round bar 3
The second outer surface 34 forms a white surface 36. As shown in FIG. 4, the white surface 36 extends linearly in the axial direction of the round bar 32, and has a total length L larger than the reading width W of the form 6.

Then, the white reference body 31 is moved from the first position (shown in FIG. 3A) at which the white surface 36 is exposed to the reading position P1 on the transport path 10 to the clock from the first position. A second position (about (B) in FIG. 3) that has been rotated approximately 60 ° in the circumferential direction.
). When the white reference body 31 is rotated to the first position, the white surface 36 is located on the same plane as the transport path 10, and the white surface 36 is irradiated with the light of the fluorescent lamp 29. Also,
When the white reference body 31 is rotated to the second position, the white surface 36
Retreats below the transport path 10, and the form 6 is transported above the white surface 36.

The apparatus main body 2 incorporates a drive mechanism 38 as a means for selectively rotating the white reference body 31 to the first position or the second position. As shown in FIGS. 3 and 5, the driving mechanism 38 has a motor 39 serving as a driving source,
A disk-shaped plate cam 41 is attached to a rotary drive shaft 40 of the motor 39.
Has been fixed. The plate cam 41 is eccentric with respect to the rotation shaft 40, and rotates eccentrically in a clockwise direction as indicated by an arrow in FIG.

The motor 39 is adjacent to one side plate 13a of the apparatus main body 2, and an idler 43 is rotatably supported on the side plate 13a via a pivot shaft 42. The idler 43 includes a roller 44 and a sector gear 45.
And The roller 44 and the gear portion 45 are
They are arranged so as to be separated from each other with the pivot shaft 42 interposed therebetween. The roller 44 is rotatably in contact with the peripheral surface of the plate cam 41, and the gear portion 45 meshes with a driving gear 46 fixed to one end of the round bar 32.

For this reason, when the plate cam 41 rotates eccentrically,
The idler 43 corresponds to the eccentric amount of the plate cam 41.
Reciprocates a predetermined angle around the pivot shaft 42 in the clockwise direction and the counterclockwise direction. Thus, the white reference body 31 is selectively rotated to the first position or the second position via the driving gear 46 meshing with the gear portion 45 of the idler 43.

As shown in FIGS. 4 and 5, the round bar 32 of the white reference body 31 has a notch 50 extending in the axial direction. The notch 50 is opened in the outer surface 34 of the round bar 32 at a position avoiding the white surface 36, and the total length of the notch 50 exceeds the reading width W of the form 6.

The notch 50 is provided in the white reference body 31.
Is turned upward to the second position and is exposed to the transport path 10 in the upward position.
The portion serving as the bottom of 0 constitutes a flat notched surface 51 that extends in the diametric direction through the vicinity of the center of the round bar 32. The cutout surface 51 is inclined linearly downward with respect to the transport path 10 when the white reference body 31 is rotated to the second position. Therefore, in the present embodiment, the cutout surface 51 of the round bar 32 functions as an inclined surface.

One edge of the notch surface 51 is
At the position adjacent to 6, it is connected to the outer surface 34 of the round bar 32. One edge of the notched surface 51 and the outer surface 3
4 constitutes a corner portion 52 that is sharp in an edge shape. The corner portion 52 extends along the axial direction of the white reference body 31, and is located on the same plane as the transport path 10 when the white reference body 31 is rotated to the second position. For this reason, the white reference body 3
The corners 52 of the first form 52 are the forms 6 sent along the transport path 10.
The sheet 6 is slidably in contact with the rear surface of the sheet 6 and supports the form 6 from below to guide the form 6 in the transport direction.

In the white reference body 31, all portions except the white surface 36, that is, the outer surface 34 and the cutout surface 51 of the round bar 32 are blackened in order to reduce the light reflectance.

As shown in FIG. 3, the second guide plate 9
An edge portion connected to the opening 23b has a flange portion 53 bent downward. The flange portion 53 is located on the front side of the white reference body 31 along the transport direction of the form 6, and a cover 55 is screwed to the flange portion 53. The cover 55 has a prismatic shape extending along the white reference body 31, and is located immediately before the white reference body 31.

The cover 55 has a concave portion 56 on a surface facing the white reference body 31. The recess 56 is provided with the white reference body 31.
6 is curved in an arc shape so as to follow the rotation trajectory of the outer surface 34, and a slight gap 57 (shown in FIG. 6) is formed between the concave portion 56 and the outer surface 34 of the white reference body 31. Have been. When the white reference body 31 is rotated to the second position, the white surface 36 enters the gap 57 between the white reference body 31 and the concave portion 56 and is covered by the concave portion 56 from the outside.

The upper surface of the cover 55 has a flat guide surface 58.
Has made. The guide surface 58 is exposed to the opening 23 b and continues to the second guide plate 8, and is located on the same plane as the transport path 10. For this reason, the guide surface 58
Is designed to guide the conveyance direction of the form 6 in cooperation with the second guide plate 8.

A guide block 60 is arranged above the cover 55. The guide block 60 has a rod shape extending in the axial direction of the white reference body 31, and is supported by the first guide plate 8 and the apparatus main body 2 via a bracket (not shown). The guide block 60 is a form 6
Has an extension 61 projecting obliquely downward along the transport direction of the guide member. The tip of the extension 61 faces the boundary portion between the guide surface 58 and the white reference body 31 with a slight gap. ing. Therefore, when the form 6 passes through the reading position P1, the extension section 61 presses the form 6 against the guide surface 58 and the corner 52 of the white reference body 31 so that the form 6 does not rise from the transport path 10.

At the end of the transport path 10, a printer 6
3 are arranged. The printer 63 prints the form 6 indicating that the reading process has been performed. The read form 6 printed by the printer 63 is stored in the first stacker table 4 via the gate 20. Be guided.

In the image reading apparatus 1 having such a configuration, before reading the image information of the form 6, the white reference body 31 is driven by the first mechanism shown in FIG.
Is rotated to the position. By this rotation, the white surface 36 of the white reference body 31 is exposed at the reading position P1 on the transport path 10. In this state, light is emitted from the fluorescent lamp 29 to the white surface 36 of the white reference body 31, and the light reflected by the white surface 36 is transmitted to the CCD image sensor 28 via the reflection mirrors 26 a and 26 b and the reduction lens 27. Be guided. Therefore, the amount of white reflected light and the RGB color balance are measured by the CCD image sensor 28, and the color balance correction control is executed here.

When the correction control is completed, the white reference body 31 is rotated approximately 60 ° clockwise through the driving mechanism 38,
The white reference body 31 moves from the first position to the second position shown in FIG. As a result, the white surface 36 retreats below the transport path 10 and the cover 55 curved in an arc shape.
And the cover 55 covers and conceals from the outside. When the white reference body 31 reaches the second position, the corner 52 of the white reference body 31
0 and the notch 50
Is exposed toward the transport path 10, and the notch 50
Is maintained in a posture inclined downward with respect to the transport path 10.

When the white reference body 31 stops at the second position,
The forms 6 accumulated on the hopper table 3 are sent to the transport path 10. When the form 6 reaches the reading position P1, the surface of the form 6 is irradiated with the light of the fluorescent lamp 29, and the reading process of the image information displayed on the surface is performed.

At this time, the form 6 is pressed against the guide surface 58 of the cover 55 and the corner 52 of the white reference body 31 by the extension 61 of the guide block 60, and guided by the guide surface 58 and the corner 52. Passes the reading position P1 in the state. Then, the form 6 on which the image information reading process has been completed is transported to the end of the transport path 10, where it is subjected to a printing process, and then sent to the first stacker table 4.

The above-described color balance correction control and reading operation are repeatedly executed for each sheet 6 or each badge process.

According to such a configuration, during the period in which the form 6 is guided to the reading position P1 on the transport path 10 and the reading process is being executed, the white reference body 31 is moved from the first position to the second position. The white surface 36 retreats below the transport path 10 and enters the gap 57 formed between the white surface 36 and the concave portion 56 of the cover 55.

For this reason, the white surface 36 of the white reference body 31 is
Even if foreign matters such as paper dust, paper chips and dust adhered to the form 6 are peeled off and fall during the reading process, the foreign matters are guided to the white surface 36 by being kept covered by the cover 55 from the outside. Or it is difficult to adhere here. Therefore, even when the read processing amount of the form 6 is increased, it is possible to prevent the white surface 36 from being stained, and therefore, it is possible to perform accurate read data correction control based on white.

Further, according to the above configuration, during the reading process of the image information, as shown in FIG.
The form 6 passes over 1. At this time, in the white reference body 31, the notch 50 is exposed to the transport path 10 and faces the back surface of the form 6 passing the reading position P1, but the notch 50 of the notch 50 Surface 51 is
It is maintained in a posture inclined downward with respect to the transport path 10.

For this reason, even if a foreign substance falls from the form 6 passing through the reading position P1, the foreign substance slides down along the cutout surface 51 as it is. Therefore, the foreign matter does not remain on the black cutout surface 51 or the outer surface 34 of the round bar 32, and the CCD image sensor 28 removes the foreign matter when reading the form 6 to be conveyed next. No misidentification as the beginning of 6 or image information,
A reading error of the image information and a transport error of the form 6 hardly occur.

As a result, accurate correction control of read data can be performed, and good image information can be stably taken in over a long period of time.

Further, according to the above configuration, the white reference body 31
Since the white surface 36 is less likely to become dirty, frequent cleaning of the white surface 36 can be omitted. Therefore, the labor required for maintenance of the white reference body 31 can be reduced, and there is an advantage that the burden on the operator can be reduced accordingly.

The present invention is not limited to the first embodiment, and FIGS. 7 and 8 show the second embodiment of the present invention.
An embodiment will be described.

The second embodiment differs from the first embodiment in the configuration of the white reference body 71, and the other basic configuration of the image reading apparatus 1 is the same as that of the first embodiment. Same as the form. Therefore, in the second embodiment, the first
The same components as those of the embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 7, the white reference body 71 includes a pair of cylindrical journals 72a and 72b, and a shaft 73 interposed between the journals 72a and 72b.
It is composed of The journal parts 72a and 72b are
They are arranged coaxially with the shaft 73 interposed therebetween, and the side plates 13a, 13a of the apparatus main body 2 are arranged via bearings 33a, 33b, respectively.
3b rotatably supported. The drive gear 46 is fixed to one of the journal portions 72 a, and the drive gear 46 meshes with the gear portion 45 of the idler 43.

The shaft 73 has a total length that exceeds the reading width W of the form 6. As shown in FIG. 8, the shaft portion 73 is radially divided into a first shaft member 74a and a second shaft member 74b.
Both ends of 4a, 74b are journal parts 72a, 72b.
It is connected to. Then, the first and second shaft bodies 74
a and 74b are arranged apart from each other in the radial direction of the shaft 73, and the shaft 73 is located between the shafts 74a and 74b.
A through hole 75 extending in the radial direction is formed. The through hole 75 has openings 77 a and 77 b that are opened at two places on the outer surface 76 of the shaft 73. These openings 77
Each of a and 77b has a slit shape extending in the axial direction of the shaft portion 73.

First and second shafts 7 facing through hole 75
The opposing surfaces of 4a and 74b are inclined in a direction approaching each other as they go from one opening 77a to the other opening 77b. For this reason, the opening width of one opening 77a is formed wider than the opening width of the other opening 77b, and the thickness of the first and second shaft bodies 74a, 74b becomes closer to the other opening 77b. The thickness is increasing. Thereby, the cross-sectional area along the radial direction of the shaft portion 73 is sufficiently ensured, and the bending deformation of the shaft portion 73 is suppressed.

The outer surfaces 76 of the first and second shafts 74a and 74b are curved in an arc shape.
And second shaft member 74 forming through hole 75
The opposite surfaces a and 74b are blackened to reduce the light reflectance.

As best shown in FIG. 8C,
A part of the outer surface 76 of the first shaft 74a forms a flat surface 78, and the flat surface 78 extends in a straight line along the axial direction of the first shaft 74a. A white tape 79 is attached to the flat surface 78. Tape 7
Reference numeral 9 denotes a white surface 80 on the outer surface 76 of the first shaft 74a, and the white surface 80 extends straight in the axial direction of the shaft 73.

The white reference body 71 has a first position (shown in FIG. 8A) at which the white surface 80 is exposed to the reading position P1 on the transport path 10 by the driving mechanism 38, and the first position. Is rotated clockwise from a second position (shown in FIG. 8B) rotated clockwise by approximately 90 °. When the white reference body 71 is rotated to the first position, the white surface 80 is positioned on the same plane as the transport path 10, and the white surface 80 is irradiated with the light of the fluorescent lamp 29. Has become.

When the white reference body 71 is rotated to the second position, the white surface 80 retreats below the transport path 10, and the form 6 is transported above the white surface 80. I have. Then, when the white reference body 71 is stopped at the second position, the white surface 80 of the white reference body 71 is
And is covered by the cover 55 from the outside. At the same time, the through hole 75 of the white reference body 71 shifts to the vertical position along the vertical direction as shown in FIG. 8B, and one of the openings 77a having a large opening width is placed on the transport path 10. At the reading position P1.

In such a configuration, when the white reference body 71 is rotated to the first position, the light of the fluorescent lamp 29 is applied to the white surface 80 of the white reference body 71. Therefore, the light reflected by the white surface 80 is reflected by the reflection mirror 26.
The light is guided to a CCD image sensor 28 via a and 26b and a reduction lens 27, where color balance correction control is executed.

When the correction control is completed, the white reference body 71 is rotated clockwise by approximately 90 ° via the driving mechanism 38,
The white reference body 71 moves from the first position to the second position. As a result, the white surface 80 retreats below the transport path 10 and is covered by the cover 55 from the outside. Also,
When the white reference body 71 reaches the second position, the opening 77a of the through hole 75 is exposed to the transport path 10, and the center of the opening 77a matches the reading position P1.

In this state, the forms 6 accumulated on the hopper table 3 are sent to the transport path 10, and the reading process of the image information recorded on the surface of the forms 6 is performed as in the first embodiment. .

During the period in which the form 6 is being read, the white reference body 71 is rotated from the first position to the second position, so that the white surface 80 retreats below the transport path 10 and the cover is covered. 55 keeps it covered from the outside. Therefore, even if foreign substances such as paper dust, paper chips, and dust adhered to the form 6 are peeled off during the reading process and fall, the foreign substances are less likely to be guided to the white surface 80 or adhered thereto.

During the reading process of the image information, the white reference
The form 6 passes over the first shaft 73. At this time, the opening 77 of the shaft 73 is located at the reading position P1 on the transport path 10.
Since a is exposed, even if the foreign matter falls from the form 6, the foreign matter is guided to the through hole 75 from the opening 77a, and falls through the through hole 75.

As a result, no foreign matter remains on the outer surface 76 of the black shaft portion 73, and the CCD image sensor 28 detects the foreign matter as the start end of the form 6 or image information as in the first embodiment. There is no false recognition. Therefore, an error in reading image information and an error in transporting the form 6 are less likely to occur, and it is possible to stably capture good image information over a long period of time.

FIG. 9 discloses a third embodiment of the present invention.

In the third embodiment, the white reference body 91
The configuration for preventing foreign matter from adhering to the image reading apparatus is different from that of the first embodiment, and the other basic configuration of the image reading apparatus 1 is the same as that of the first embodiment.

As shown in FIG. 9, the white reference body 91 is constituted by a solid round bar 92 having a circular outer surface 93. A part of the outer surface 93 of the round bar 92 forms a flat surface 93a extending linearly along the axial direction, and a white tape 94 is attached to the flat surface 93a. The tape 94 forms a white surface 95 on the outer surface 93 of the round bar 92, and the white surface 95 extends linearly in the axial direction of the round bar 92. And the round bar 9 excluding this white surface 95
The outer surface 93 of the second 2 is blackened to reduce the light reflectance.

The white reference body 91 has a white surface 95 on the transport path 1.
A first position (shown in FIG. 9A) exposed at the reading position P1 above the second position (see FIG. 9A), and a second position (shown in FIG. 9 (B)) is supported by the apparatus main body 2 so as to be rotatable.

When the white reference body 91 is rotated to the first position, the white surface 95 is positioned on the same plane as the transport path 10, and
The light from the fluorescent lamp 29 is applied to the white surface 95.
When the white reference body 91 is rotated from the first position to the second position, the white surface 95 is held in a downward position below the transport path 10.

The drive mechanism 97 for rotating the white reference body 91 to the first position or the second position has a drive gear 98 fixed to the rotary drive shaft 40 of the motor. The drive gear 98 meshes with an idler gear 99, and the idler gear 99 meshes with a driven gear 100 fixed to one end of a round bar 92.

Therefore, when the drive gear 98 is driven to rotate counterclockwise by the motor, the white reference body 91 rotates counterclockwise, and the white reference body 91 is moved to the first position or the second position. The position is selectively operated.

As shown in FIG. 9, a bracket 102 extending downward from the transport path 10 is fixed to the lower surface of the second guide plate 9. The lower end of the bracket 102 is located below the white reference body 91, and the brush support 103 is fixed to the lower end of the bracket 102. The brush support 103 is located directly below the white reference body 91, and a brush 104 as a cleaning body is attached to the brush support 103. The brush 104 extends in the axial direction of the white reference body 91, and the brush 10
4 is in contact with the outer surface 93 of the round bar 92.

In such a configuration, when the white reference body 91 is rotated to the first position, the light of the fluorescent lamp 29 is applied to the white surface 95 of the white reference body 91. Therefore, the light reflected on the white surface 95 is reflected by the reflection mirror 26.
The light is guided to a CCD image sensor 28 via a and 26b and a reduction lens 27, where color balance correction control is executed.

When the correction control is completed, the white reference body 91 is rotated approximately 180 ° in the counterclockwise direction via the drive mechanism 97, and the white reference body 91 moves from the first position to the second position. . This causes the white surface 95 to retreat below the transport path 10 and the outer surface 93 of the round bar 92 to move
Exposure to In this state, the forms 6 accumulated on the hopper table 3 are sent to the transport path 10, and the reading process of the image information recorded on the surface of the forms 6 is performed as in the first embodiment.

During the period in which the form 6 is being read, the white surface 95 of the white reference body 91 is held in a downward position below the transport path 10. Even if foreign substances such as paper pieces and dust are peeled off during the reading process and fall, the foreign substances are not guided to the white surface 95 or adhered thereto.

During the reading process of the image information, the form 6 passes along the outer surface 93 of the white reference body 91 as shown in FIG. At this time, if foreign matter such as paper dust or a piece of paper adheres to the form 6, the foreign matter may move onto the outer surface 93 of the white reference body 91. However, when the reading of the form 6 is completed, the white reference body 91 is
One rotation is made in the clockwise direction via 7. This allows
The tip of the brush 104 slides on the outer surface 93 of the white reference body 91, and the foreign matter transferred to the outer surface 93 of the white reference body 91 is forcibly scraped off by the tip of the brush 104.

As a result, no foreign matter remains on the outer surface 93 of the black round bar 92, and the CCD image sensor 28 does not erroneously recognize the foreign matter as the beginning of the form 6 or image information. Therefore, the reading error of the image information and the form 6
Is less likely to occur, and good image information can be stably taken in over a long period of time.

Further, the white surface 95 reaches the first position while the white reference body 91 makes one rotation around the axis, and the white surface 9
5 is irradiated with the light of the fluorescent lamp 29,
The color balance correction control can be executed at the same time as the foreign object 3 is forcibly removed.

Further, according to the above configuration, the white reference body 91
While the white surface 95 moves from the second position to the first position, the white surface 95 enters the concave portion 56 of the cover 55 and is covered and covered by the cover 55 from the outside. Therefore, the downward facing white surface 95 is
During the period until exposure to zero, foreign matter hardly adheres to the white surface 95, and accurate read data correction control based on white becomes possible.

In addition, since the white surface 36 is hardly stained,
Frequent cleaning of the white surface 36 can be omitted, and there is an advantage that maintenance of the white reference body 91 can be easily performed.

FIG. 10 discloses a fourth embodiment of the present invention.

The fourth embodiment is a further development of the third embodiment, and the basic configuration of the image reading apparatus 1 is the same as that of the third embodiment.

As shown in FIG. 10, the black outer surface 93 of the white reference body 91 is exposed to the transport path 10 before the form 6 reaches the reading position P1, so that the form 6
If there is any foreign matter that cannot be completely removed by the brush 104 on the outer surface 93 exposed to the transport path 10 just before the image reading position P1 is reached, the CCD image sensor 28 erroneously recognizes the foreign matter as the beginning of the form 6 or as image information. There is a possibility that it may occur.

However, in the sensor unit 24 of the present embodiment, when the outer surface 93 of the white reference body 91 is exposed to the transport path 10 and the image information of the form 6 is read,
It monitors whether or not the image information guided to the D image sensor 28 is abnormal.

More specifically, if a foreign matter is attached to the black outer surface 93, the foreign matter is erroneously recognized as the start end of the form 6, even though the form 6 has not reached the reading position P1. From here, the reading range of the form 6 is set. For this reason, the CCD image sensor 28 generates an error such that the area to be read is shifted with respect to the dimensions of the form 6 to be read, or the form 6 is shifted from the position on the transport path 10 where the form 6 should pass. Is detected.

When this error is detected, a control signal is sent from the CCD image sensor 28 to the motor of the drive mechanism 97, and as shown by the angle θ in FIG. 10, foreign matter on the outer surface 93 deviates from the reading position P1. The white reference body 91 is rotated to the position. Therefore, if the reading process is executed again in this state, the image information of the form 6 can be accurately read.

Note that, in the fourth embodiment, CC
When an error is detected by the D image sensor 28, the white reference body 91 is rotated once around the axis without performing the reading process of the form 6, and the foreign matter adhering to the outer surface 93 is removed again by the brush 104. You may do it.

In carrying out the present invention, the record carrier to be read is not limited to the form, but may be a document on which image information such as characters is drawn.

[0100]

According to the present invention described in detail above, even if foreign substances such as paper dust, paper chips and dust adhered to the record carrier are peeled off during the reading process and fall, the foreign substances adhere to the white surface. Can be prevented from remaining here. For this reason, the white surface is less likely to be stained, and accurate read data correction control based on white can be performed.

At the same time, the use of the cleaning body that is in sliding contact with the outer surface of the white reference body makes it possible to forcibly scrape off the foreign substances attached to the outer surface of the white reference body. For this reason, the sensor unit does not mistakenly recognize the foreign matter on the outer surface as the start end of the record carrier or the image information. Good image information can be stably captured.

Further, since the frequent cleaning work of the white surface is not required, the labor required for maintenance of the white reference body can be reduced, and the burden on the operator can be reduced by that much, and the operation of the apparatus can be reduced. There is an advantage that efficiency can be increased.

[Brief description of the drawings]

FIG. 1 is a side view schematically showing an optical image reading device according to a first embodiment of the present invention.

FIG. 2 is a plan view illustrating a positional relationship between a drive roller and a white reference body on a transport path.

FIG. 3A is a view in which a white reference body is rotated to a first position,
FIG. 4 is a cross-sectional view illustrating a state where the white surface is exposed to a transport path.
(B) is a sectional view showing a state in which the white reference body is rotated to the second position and the white surface is covered by the cover.

FIG. 4 is a plan view of a white reference body.

FIG. 5 is a perspective view showing a positional relationship between a white reference body and a driving mechanism thereof.

FIG. 6 is a cross-sectional view showing a state where a white surface of a white reference body has entered a concave portion of a cover.

FIG. 7 is a plan view of a white reference body according to a second embodiment of the present invention.

FIG. 8A shows a state in which a white reference body is rotated to a first position,
FIG. 4 is a cross-sectional view illustrating a state where the white surface is exposed to a transport path.
FIG. 5B is a cross-sectional view illustrating a state in which the white reference body has been rotated to the second position and the opening of the through hole has been exposed to the transport path.
(C) is a sectional view of a white reference body.

FIG. 9A shows a third embodiment of the present invention in which a white reference body is rotated to a first position, a white surface thereof is exposed to a conveyance path, and an outer surface is formed by a brush. Sectional drawing which shows the state which contacted. FIG. 4B is a cross-sectional view illustrating a state in which the white reference body has been rotated to the second position, the white surface has retreated from the transport path, and has come into contact with the brush. (C) is a sectional view of a white reference body.

FIG. 10 is a cross-sectional view illustrating a state in which a white surface of a white reference body is rotated to a second position according to the fourth embodiment of the present invention.

[Explanation of symbols]

 6 ... Record carrier (form) 10 ... Convey path 24 ... Sensor unit 29 ... Light source (fluorescent lamp) 31,71,91 ... White reference body 34,76,93 ... Outer surface 36,80,95 ... White surface 55 ... Cover 97: driving means (driving mechanism) 104: cleaning body (brush)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H109 CA21 5B047 AA01 BA01 BC14 BC18 BC30 CA30 DA04 5C072 AA01 BA08 BA20 EA07 FB12 NA01 RA16 XA01

Claims (9)

[Claims] 1. A transport path for transporting a sheet-shaped record carrier, and irradiating the record carrier conveyed along the transport path with light and receiving reflected light from the record carrier, A sensor unit that optically reads image information recorded on a record carrier and an outer surface that is exposed to the transport path, and the output of the sensor unit that reads the image information on a part of the outer surface is the same. A white reference body having a white surface for correction as described above, wherein the white reference body has a first position where the white surface is exposed to the transport path and receives the light, and the recording When reading the image information of the carrier, the white surface is installed on the transport path so as to be rotatable around an axis over a second position retreating below the transport path, and the white reference body is provided. of In circumference, when the white reference body is rotated to the second rotational position, the image reading apparatus characterized in that a cover covering the white surface. 2. The white reference body according to claim 1, wherein the cover has a concave portion curved in an arc shape along a rotation locus of an outer surface of the white reference body. ,
An image reading apparatus wherein the white reference body enters the recess when the white reference body is rotated to the second position. 3. The method according to claim 1, wherein
The white reference body has a black outer surface except for a white surface, and a portion of the outer surface that is exposed to the transport path when the white reference body is rotated to the second position. Is an image reading apparatus having an inclined surface which is inclined downward with respect to the transport path. 4. The recording medium according to claim 1, wherein the transport path has a guide plate for guiding a transport direction of the record carrier, and the cover is continuous with the guide plate. An image reading apparatus having a guide surface for guiding the transport direction of the record carrier. 5. The white reference body according to claim 3, wherein the white reference body has a corner defined by an outer surface thereof and an inclined surface, and the corner is such that the white reference body is located at a second position. An image reading device, which guides the transport direction of the record carrier when rotated. 6. The method according to claim 1, wherein
The white reference body includes a slit-shaped through-hole extending in the axial direction at a position avoiding the white surface, and the through-hole is formed in a vertical direction when the white reference body is rotated to the second position. An image reading apparatus which shifts to a vertical position in accordance with (1), and an opening portion opened on the outer surface of the white reference body is exposed to the transport path. 7. A transport path for transporting a sheet-shaped record carrier, and when the record carrier reaches a reading position on the transport path, the record carrier is irradiated with light, and reflected light from the record carrier is reflected. A sensor unit that optically reads image information recorded on the record carrier by receiving light, and has a black-processed circular outer surface exposed on the transport path, and a part of the outer surface A first position at which a flat white surface for correcting the output of the sensor unit for reading image information to be the same, a first position at which the white surface advances to a reading position on the transport path, and the record carrier; When reading the image information, a rod-shaped white reference body installed on the transport path so as to be rotatable around the axis over a second position where the white surface retreats below the transport path; Drive means for selectively rotating the reference body to the first position or the second position; and a drive means disposed around the white reference body, which slides on the outer surface and the white surface when the white reference body rotates. An image reading device, comprising: a cleaning member that contacts as much as possible. 8. The cleaning device according to claim 7, wherein the cleaning body is disposed on an opposite side of the conveyance path with the white reference body interposed therebetween, and the cleaning body is disposed between the white reference body and the conveyance path. An image reading apparatus, wherein a cover that covers an outer surface of the white reference body including the white surface is disposed therebetween. 9. The method according to claim 7, wherein
The sensor unit, when the outer surface of the white reference body is exposed to the transport path and reads the image information of the record carrier, monitors whether there is an abnormality in the data indicating the image information, and monitors the data. An image reading apparatus, wherein when there is an abnormality, the white reference body is rotated via the driving means to shift the position of the outer surface of the white reference body with respect to the reading position.