JPH07327111A - Double side image reader - Google Patents

Abstract

PURPOSE:To obtain the reader with simple structure and high read accuracy in the original transfer reader in which double side simultaneous reading of an opaque original and reading of a transparent original are both available with respect to the reader reading information recorded on a sheet medium as image information. CONSTITUTION:A 1st light source lamp 11 and a 1st optical device 12 are arranged to one side of an original path and a 2nd light source lamp 21 and a 2nd optical device 22 are arranged to the other side. Transparent guides 52, 54 are formed on a guide face of original to which the 2nd optical light source lamp 21, a read optical path 13 of the 1st optical device 12 is made opposite to the 2nd light source lamp 21, the 2nd light source lamp 21 is lighted and the 1st light source lamp 11 is extinguished and the 1st optical device reads a transparent original. The difference in the luminous quantity resulting from reading a transparent original and an opaque original is absorbed by providing a different reflectance for reflecting mirrors or installing a reflector. Whether an original is a transparent original or an opaque original is discriminated through the provision of an original detection mechanical sensor 32 and an optical sensor 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for reading characters, figures, and other information recorded on a sheet-shaped medium such as paper as image information, and both sides (front and back sides) of the medium.
The present invention relates to an apparatus capable of simultaneously reading the information described in 1. and an opaque medium such as ordinary office paper and a transparent medium such as a base paper for an overhead projector.

[0002]

2. Description of the Related Art An image of a medium such as opaque paper or a transparent resin sheet on which information is recorded (hereinafter referred to as "original", an opaque medium is referred to as "opaque original", and a transparent medium is referred to as "transparent original"). As an image reading device that reads as information,
There are a fixed original type having a transparent original table (glass top plate) on which an original is fixed and a movable original type having an automatic paper feeder.

Conventionally, a fixed document type image reading apparatus is provided with a reading optical device (simply referred to as "optical device") that runs along the lower surface of a transparent document table and an optical device that runs inside a document holding cover. There is known a device capable of simultaneously reading both sides of a document. There is also known a device in which a light source lamp that travels in synchronization with an optical device that runs on the lower surface of the transparent document table is provided in the document pressing cover so that a transparent document can be read.

On the other hand, in the moving original type image reading apparatus, by disposing the optical devices on both sides of the original passage,
There is known a device capable of simultaneously reading both sides of a document.

Further, as an apparatus capable of reading both a fixed original and a moving original, an automatic paper feeder is provided at one running end side of the optical device of the transparent original table so that the fixed original reading optical device is automatically operated. There is also known a device in which a moving document is read by using the same optical device as in the case of reading a fixed document while the document is stopped below the document path by the sheet feeding device.

[0006]

When reading a transparent original,
Usually, this is performed using a fixed original image reading device. The fixed-type image reading device has the advantage that it is technically less difficult and its operation is stable, but when reading multiple documents, the operator must set and remove the documents one by one. is there. Further, there is a fixed document type device having a structure in which an automatic document feeding / discharging device for a document on a transparent document table is provided, but there is a problem in that the structure becomes complicated and the stability of the operation decreases.

An object of the present invention is to provide an image reading apparatus of a moving original type capable of simultaneously reading both sides of an opaque original and reading a transparent original, and also serves as an optical device for various reading operations. By doing so, it is an object to obtain the above-mentioned device having a simple structure with a small number of parts, and further to obtain the above-mentioned device capable of reading a fixed original. Further, it is possible to obtain the above-mentioned device capable of performing an accurate reading operation by automatically detecting whether the original is a transparent original or an opaque original, and further rationally setting an accurate white reference during reading. An object of the present invention is to obtain the above device.

[0008]

According to the present invention, the first light source lamp 11 and the first optical device 12 are arranged on one side,
The guide surfaces on both sides of the portion of the document passage 51 in which the second light source lamp 21 and the second optical device 22 are arranged on the other side are transparent guides 52 and 54, respectively.
The reading optical path 13 of the optical device 12 is opposed to the second light source lamp 21, the second light source lamp 21 is turned on, the first light source lamp 11 is turned off, and the transparent original is read through the reading optical path 13 of the first optical device. I am trying.

In a reading apparatus provided with a fixed original reading unit and a movable original reading unit, the first light source lamp 11 and the first light source lamp 11 are provided on the carrier 17 which runs along the lower surface of the transparent original table 53 on which the fixed original is placed. The first optical device 12 is mounted.

There is a large difference in the amount of read light incident on the photoelectric conversion element when a transparent original is read using a light source lamp having the same illuminance and when an opaque original is read. On the other hand, the first optical device 1 mounted on the carrier 17
2 will typically have more reflective surfaces than the second optical device 22. Therefore, as a means for avoiding the above-mentioned difference in the light amount, one having a reflectance lower than that of the reflecting mirror 24 of the second optical device is used as the reflecting mirror 14 of the first optical device, and the illuminance of the first light source lamp 21 is the first. Light source lamp 1
Use a light intensity lower than 1.

A second means for avoiding the difference in the light quantity is to provide an illuminance switching means 62 in the power supply circuit of the second light source lamp 21 and reduce the illuminance of the lamp when reading a transparent original.

A third means for avoiding the difference in light quantity is to use the opaque guide surface 50 as the opaque guide surface 50 as the original guide surface on the side opposite to the opaque original reading position C of the second optical device 22.
In addition, the reflector 63 is provided to collect the reflected light at the reading position C of the opaque original and not irradiate the reading position B of the transparent original.

When a transparent original is fed into the original passage through an automatic paper feeder having a paper feed roller 35 and a separation pad 36 pressed against the peripheral surface thereof, pressing force releasing means 38 and 40 for the separation pad are provided. At the time of feeding a transparent document, the pressing force releasing means 38 and 40 release or reduce the pressing force of the separation pad 36.

A mechanical sensor 32 for detecting a document and an optical sensor 33 are provided on the upstream side of the document passage 51, and are transparent when the mechanical sensor 32 detects the document and the optical sensor 33 does not detect the document. By performing the reading operation of the original, the reading operation of the transparent original and the opaque original can be automatically switched.

In the double-sided image reading apparatus in which the first optical device 12 is mounted on the carrier 17 which is movable along the document passage 51, the white plate 65 for setting the white reference of the second optical device is provided in the document passage 51. The engaging means 6 for guiding the white plate to the carrier and urged by the return spring 66 in the direction of retreating from the document passage 51.
9, 70 and engagement releasing means 71 for releasing this engagement are provided.

[0016]

In the double-sided image reading apparatus of the present invention, the document passage 51 is provided.
When the original passing through the sheet is a one-sided opaque original, the original is read by the first light source lamp 11 and the first optical device 12 or the second light source lamp 21 and the second optical device 22, and is a two-sided opaque original. At this time, the respective surfaces of the first light source lamp 11 and the first optical device 12 and the second light source lamp 21 and the second optical device 22 are read.

When the original is a transparent original, the reading optical path 13 of the first optical device is opposed to the second light source lamp 21,
The original is read with the second light source lamp 21 lit and the first light source lamp 11 off.

A photoelectric conversion element having the same sensitivity (generally CC
When D) is used, it is necessary to lower the illuminance of the light source lamp when reading a transparent original than when reading an opaque original, but in the structure according to claims 2 and 3, the reflection loss of the second optical device is reduced and The first light source lamp 11 as the two light source lamp 21
The use of a light source having a smaller illuminance,
With this configuration, this problem is solved by switching the illuminance of the second light source lamp 21 at the time of reading the transparent document, and by increasing the illuminance at the opaque document reading position C with the reflector 63 in the configuration of claim 5.

In an automatic feed device having a structure in which the original fed into the original passage 51 is separated by the separation pad 36, the transparent original, which is a synthetic resin sheet, generates static electricity and adheres to the separation pad. Automatic feeding may not be possible. Therefore, when the original is a transparent original, the pressing force of the separation pad 36 is released or reduced to prevent the original from being charged due to the rubbing of the separation pad 36 and to prevent the original from being attracted to the separation pad 36. In this case, since it becomes impossible to separate the original from the transparent original, the transparent originals are manually supplied to the apparatus one by one. When it is necessary to automatically separate and feed transparent originals, an automatic paper feed having a structure that separates the originals without using a separation pad, for example, a separation roller 36a with a torque limiter or locking claws that lock both corners of the leading edge of the original Use the device.

Whether the device performs the operation of reading an opaque original or the operation of reading a transparent original and whether to release the pressing force of the separation pad may be instructed by an operator. By using two types of sensors 32 and 33 of a mechanical type and an optical type as the sensor of 1, it is possible to automatically discriminate between a transparent original and an opaque original and switch the operation. That is, when the original is an opaque original, the original is detected by both the mechanical sensor 32 and the optical sensor 33. On the other hand, when the original is a transparent original, the optical sensor 33 does not detect the original. Therefore, the operation is switched depending on whether both the sensors 32 and 33 detect the document or only the mechanical sensor 32 detects the document. When both the sensors 32 and 33 do not output the document detection signal, it may be determined that there is no document (function as an empty sensor) or a paper feed error.

In addition, the structure in which the white plate 65 for the second optical device 22 is provided in the above structure can prevent the white plate 65, which is the white reference of the second optical device 22, from being contaminated by rubbing the original. The white plate 65 can be moved forward and backward when the white reference is set and when the document is read without providing a dedicated drive source. That is, when the white reference is set, the locking means 69,
By locking 70 and moving the carrier 17, the white plate 65 is advanced to the reading position C of the second optical device, and when the setting of the white reference is completed, the locking release device 71 is used to move the carrier 17 and the white plate 65. Release the lock with and return spring 66
The white plate 65 is retracted to the standby position where it does not rub against the document by the urging force of.

[0022]

FIG. 1 is a schematic side view showing an embodiment of the present invention. The illustrated apparatus includes a fixed original reading unit 1 and a moving original reading unit 2, and the moving original reading unit 2 adopts the configuration of the present invention. The fixed document reading unit 1 includes a transparent document table 53, a first light source lamp 11 and a first optical device 12 that run along the lower surface of the transparent document table 53, and a document cover (not shown) that is attached to the upper surface of the transparent document table. It has and. The moving document reading unit 2 includes an automatic paper feeding device 3, a first light source lamp 11 and a first optical device 12 which are stopped below a document passage.
It is composed of a second light source lamp 21 and a second optical device 22 arranged above the document passage 51.

Double-sided reading of a document passing through the document passage 51 is performed by the first optical device 12 and the second optical device 22. The transparent original is read by illuminating the transparent original passing through the original passage 51 with the second light source lamp 21 and through the reading optical path 13 of the first optical device 12.

The fixed original is prepared by moving the original fixed on the transparent original table 53 through the first optical device 12.
Reading of a fixed original with such a structure can improve the reading accuracy. In the illustrated apparatus, the fixed reading unit 1 is provided so as to enable fixed reading when accurate reading position detection is necessary, for example, when a read character original is converted into code data by an OCR (optical character recognition device). Is provided. Since the structure of the fixed reading unit 1 is not different from that of the conventional device, description and illustration thereof will be omitted.

The moving reading section 2 is provided with a hopper 31 for loading a document and a stacker 34 for receiving the read document at both ends of the document path 51. A mechanical sensor 32 and an optical sensor 33 for detecting a document fed into the apparatus are provided at the document feeding end of the hopper 31. The mechanical sensor 32 is, for example, a micro switch, and detects the passage of the document by contacting the actuator with the document. The optical sensor 33 is, for example, a transmissive photoelectric sensor, and detects an opaque document by blocking its optical path when the opaque document passes between the light emitter and the light receiver. The transparent original is detected by the mechanical sensor 32 but not by the optical sensor 33.

Adjacent to these sensors 32 and 33, there are provided a paper feed roller 35, a separation pad 36 in contact with the peripheral surface of the paper feed roller 35, and an initial conveyance spring 45. The peripheral surface of the paper feed roller 35 and the separation pad 36 are made of a material having a large friction coefficient, and the initial conveyance spring 45 is made of a material having a small friction coefficient. The initial conveyance spring 45 presses the lower surface of the leading end of the original on the hopper 31 against the peripheral surface of the paper feed roller 35 so that a sufficient conveying force is applied to the lower surface of the original. Further, the separation pad 36 abuts on the upper surface of the conveyed document group, and imparts a frictional resistance force to the second or more documents to allow only one document to pass.

A first feed roller 46 is arranged on the original feeding side of the paper feed roller 35. The first feed roller 46 has a structure in which a document is nipped and fed by a drive roller 46a and a driven roller 46b. Paper feed roller 35
Between the first feed roller 46 and the first feed roller 46, guide plates 48, 48 for guiding a document are provided. The first feed roller 46 feeds the original so that the original obliquely abuts on the upper surface of the extension 54 of the transparent original table. First feed roller 46
The original sent from the above-mentioned sheet abuts on the extension portion 54 of the transparent document table, then bends and travels along the upper surface of the extension portion 54.

In order to ensure that such a document travels, the upper surface of the first feed roller 46, which guides the bending of the document at the exit side thereof, does not lift the document from the extension 54 of the transparent document table. A guide plate 49 is provided. First reading position A of the moving original by the first optical device 12
Is set to a position after the original is guided by the upper guide plate 49 along the extension 54 of the transparent original table.

A document passage 51 connected to the upper guide plate 49
An upper surface glass 52 that guides the upper surface of the document is arranged on the downstream side of. The upstream side of the upper surface glass faces the end of the extension 54 of the transparent document table, and the document passage 5
The reading position B of the transparent original is set at a position where both sides of 1 are transparent plates 52 and 54, and the second light source lamp 21 is arranged above the upper surface glass 52 at the transparent original reading position B. .

On the downstream side of the upper surface glass 52, a document passage 51 is provided.
The second reading position C for the opaque original is set at a position where the upper glass 52 and the lower guide plate 50 face each other. A second feed roller 47 having the same structure as the first feed roller 46 and driven synchronously with the first feed roller 46 is disposed on the exit side of the second reading position C of the opaque document. The document sent from the stack is discharged onto the stacker 34.

The tip of the above-mentioned separation pad 36 has an urging spring 38 in which an intermediate portion is pivotally supported by a pin 37 erected on a stationary member.
Is urged toward the paper feed roller 35 at the lower end of the. The upper end of the urging spring 38 is pushed by a cam 40 which is reciprocally rotated by 90 degrees by a motor 39. A sensor protrusion 42 is integrally provided on the cam, and a mechanical or optical cam sensor 43 for detecting the protrusion 41 of the cam and the sensor protrusion 42 is provided.

The protruding portion 41 of the cam 40 is the urging spring 3.
In the state shown in FIG.
8 is pushed counterclockwise in the figure, and the lower end of the biasing spring 38 pushes the separation pad 36 against the sheet feed roller 35 side. At this time, the sensor protrusion 42 is detected by the cam sensor 43. On the other hand, when the cam 40 is rotated approximately 90 degrees counterclockwise from the illustrated state, the pushing motion of the upper end of the biasing spring 38 by the cam 40 is released, and the biasing force of the biasing spring 38 on the separation pad 36 is released. At this time, the protruding portion 41 of the cam is connected to the cam sensor 4
Detected in 3.

The first optical device 12 is mounted on the carrier 17 that runs along the lower surface of the transparent original table 53, and
A sheet of reflecting mirror 14, an imaging lens 15, and a CCD sensor 16
It is composed of. At the first reading position A, the lower surface of the opaque document passing through the document passage 51 has the first light source lamp 1
Illuminated by 1 and passed through a first reading optical path 13 indicated by an imaginary line 18, an image is formed on a CCD sensor 16 by an imaging lens 15 and read as an electric signal.

The first reading optical path 13 includes five reflecting mirrors 14.
It reaches the lens 15 after being reflected six times between. The reason why such a large number of reflecting surfaces are provided is to satisfy both the requirements of downsizing the carrier 17 and ensuring a sufficient optical path length. However, due to reflection loss, the CCD sensor is provided. The amount of light reaching 16 decreases. In other words, the first light source lamp 11 has a larger illuminance than the second light source lamp 21, which will be described later, in consideration of the large reflection loss.

The second optical device 22 is a housing 7 of the moving reading unit.
It is arranged inside and is composed of three reflecting mirrors 24, an imaging lens 25 and a CCD sensor 26. As described above, the second light source lamp 21 is arranged above the transparent original reading position B where the both sides of the original passage 51 are the two transparent plates 52 and 54. The second reading position C of the opaque original
Is set at a position where the lower surface of the document passage is an opaque lower surface guide plate 50. At the second reading position C, the upper surface of the opaque original is illuminated by the second light source lamp 21, reflected by the three reflecting mirrors 24, 24, 24, and then,
It is read by the CCD sensor 26 through the imaging lens 25. Since the second optical device 22 can secure a relatively large installation space, the reflection loss of the second reading optical path 23 is reduced to three by setting three reflection points. Therefore, the illuminance of the second light source lamp 21 is smaller than the illuminance of the first light source lamp 11 because the reflection loss is small.

For the transparent original, the carrier 17 is further moved to the left from the position shown in FIG. 1 and stopped at the position where the reading optical path 13 of the first optical device becomes the transparent original reading position B, and the second.
With the light source lamp 21 lit and the first light source lamp 11 off, the CCD sensor 16 of the first optical device reads.
When reading a transparent original, the illuminance of the light source lamp may be smaller than that when reading an opaque original because there is no reflection loss on the original surface. In this embodiment, the light amount of the second light source lamp 21 is smaller than the light amount of the first light source lamp 11 for the reason described above. Therefore, when the transparent original is read, the light amount entering the CCD sensor 16 of the first optical device becomes excessive. Can be prevented.

In the device of the illustrated embodiment, the first optical device 12
Also, whether the second light source lamp 21 performs the reading operation of the transparent original or the reading operation of the opaque original is automatically determined by the signals of the sensors 32 and 33 provided at the tip of the hopper. That is, if the original is an opaque original, both the mechanical sensor 32 and the optical sensor 33 detect that the original has been supplied. Therefore, when an original detection signal is output from both the sensors 32 and 33, the original is opaque. The original scanning operation is performed. On the other hand, if the original is a transparent original, the optical sensor 3
Since No. 3 does not detect an original, when the original detection signal is output only from the mechanical sensor 32, the transparent original is read.

In the structure in which the separation pad 36 is provided as the original separation mechanism as shown in FIG. 1, the surface of the original may be rubbed by the separation pad 36 during the feeding of the transparent original, and the original may be scratched. In addition, a transparent original made of a transparent resin sheet often generates static electricity due to rubbing against the separation pad 36 and is adsorbed to the separation pad 36, so that automatic feeding cannot be smoothly performed. In consideration of this fact, the apparatus shown in FIG. 1 rotates the cam 40 counterclockwise 90 degrees from the illustrated state when a transparent document is supplied, that is, when only the mechanical sensor 32 outputs a document detection signal. Separation pad 3 of biasing spring 38
The pressing force against 6 is released so that the separation pad 36 does not rub the document. Therefore, in the apparatus shown in FIG. 1, the supply of transparent originals is limited to one by one, and a plurality of transparent originals cannot be placed on the hopper 31 and automatically supplied.

When it is desired to automatically separate and feed transparent originals, a separating structure as shown in FIG. 2 using a separating roller 36a with a torque limiter instead of the separating pad may be adopted. In this case, since the detection of whether the original is a transparent original or an opaque original may be performed on the downstream side of the separation roller 36a, the mechanical sensor 32 and the optical sensor for detecting the passage of the original. The pair with 33 is the paper feed roller 35.
And the first feed roller 46.

As a structure for preventing the amount of light incident on the CCD sensor 16 of the first optical device from becoming excessive when reading a transparent original, the structure shown in FIG. 3 or FIG. 4 is used in addition to the structure shown in FIG. It is possible.

The structure shown in FIG. 3 is such that the power supply circuit of the second light source lamp 21 can be switched between the circuit 61a with the voltage drop device 60 interposed and the circuit 61b without the voltage drop device 60. When the document detection signal is output but not from the optical sensor 33, the switch 6
2 is switched to the circuit side provided with the voltage lowering device 60 to reduce the light amount of the second light source lamp 21.

In the structure shown in FIG. 4, a reflector 63 is provided on the second light source lamp 21, and the reflector 63 is provided so that the reflected light is condensed at the second reading position C of the opaque original. According to this structure, when the transparent original is read, the reflected light of the reflector 63 is applied to the opaque lower surface guide plate 50 and does not contribute to the reading of the original, and when reading the opaque original, the second light source lamp 21 is used. Since the original is illuminated by the direct light and the reflected light from the reflector 63, the original can be read with a large illuminance.

The reading of the reflection original requires a white reference for setting the reading level. In the conventional device, the second
Although the white reference for the optical device 22 is provided on the upper surface of the lower guide plate 50, in the case of such a structure, there is a problem in that the surface of the white reference is rubbed against the original to be soiled and an error occurs in the set level. It was

Therefore, the illustrated device has a structure for setting the white reference of the second optical device 22 and has a white plate 65 for setting the white reference.
Is provided so that it can be moved back and forth, the advance is performed by the movement of the carrier 17, and the return is performed by the return spring 66. That is, in FIG. 1, the white plate 65, which serves as a white reference for the second optical device 22, is guided by slide rails on both sides and is extended by the transparent platen 54 and the lower guide plate 50.
It is provided so as to be able to advance into the document passage 51 along the upper surface of the first feed roller 46, and is normally located below the first feed roller 46 by being pulled by the return spring 66.

Claws 68 and 69 having a rotation fulcrum 67 in the center are vertically projected at the central portions on both sides of the white plate 65. The claws 68, 69 are integrally urged by a spring spring (not shown) counterclockwise around the rotation fulcrum 67, and abut on a stopper that restricts the counterclockwise rotation at a position where the claws 68, 69 stand. It is held in the standing position shown in the figure. That is, when a force stronger than the biasing force of the mainspring that biases the claws 68 and 69 is applied, the claws 68 and 69 rotate clockwise in the drawing and fall down. The urging force of the main spring that raises the claws 68 and 69 is larger than the urging force of the return spring 66.

On the other hand, on both sides of the upper surface of the carrier 17, projections 70 are provided at positions to be engaged with the claws 69 projecting downward from the white plate.
Is provided. The projection 70 is provided with its lower end pivotally supported by a pin perpendicular to the plane of the drawing, and is biased clockwise by a spring spring (not shown) in the figure, and rotates clockwise in the standing position. It is regulated by a stopper that prevents the above, and is held in the standing state shown in the figure. Therefore, the protrusion 70 falls in that direction when a counterclockwise biasing force is applied. Further, fixed locking protrusions 71 are provided on both sides of the upper portion of the document passage 51 at positions where they are engaged with the claws 68 protruding upward from the white plate. The locking protrusion 71 is provided at a position where the white plate 65 contacts the claw 68 after the white plate 65 reaches the second reading position C.

In the above structure, when setting the white reference of the second optical device 22, first, the carrier 17 is moved to the right until the protrusion 70 of the carrier is located on the right side of the claw 69 in the drawing. When the projection 70 comes into contact with the claw 69 when it moves rightward, the projection 70 lays down counterclockwise in the drawing and passes below the claw 69. Next, when the carrier 17 is moved to the left, the claw 69 and the projection 70 come into contact with each other, and at this time, the projection 70 cannot fall down.
The fall of 9 is prevented by the urging force of the spring spring, which is stronger than the urging force of the return spring 66, so that the claw 69 and the protrusion 70 engage with each other to extend the return spring 66, and the white plate 65
Is moved to the left with the carrier 17. Due to this leftward movement, the white plate 65 advances into the original passage 51 and reaches the second reading position C. At that time, the reading operation of the second optical device 22 is performed to set the white reference.

After the white reference is set, the carrier 17
When the is moved to the left, the locking projection 71 comes into contact with the upper claw 68, and in this state, a driving force acts to move the lower claw 69 further leftward from the projection 70 of the carrier. Therefore, the claws 68 and 69 are rotated rightward to disengage the claw 69 from the protrusion 70 of the carrier, and the biasing force of the return spring 66 causes the white plate 65 to return to the standby position below the first feed roller 46. The white reference of the first optical device 12 may be provided on the transparent document table 53 below the first feed roller 46, as in the conventional device.

[0049]

According to the above-described structure of the present invention, it is possible to obtain a moving original image reading apparatus capable of reading both sides of an opaque original and reading a transparent original. Further, since the transparent original is read using the light source lamp of one of the two optical devices provided for reading both sides of the transparent original and the other optical device, the device structure can be simplified.

Further, with the structure shown in the illustrated embodiment, it is possible to prevent the amount of the reading light for the CCD sensor from becoming excessive when reading the transparent original. Further, since the transparent original reading operation and the opaque original reading operation are automatically selected by the automatic determination of the original, the operation is not complicated even when the transparent original and the opaque original are alternately read.
In addition, it is possible to prevent operator's operation mistake. Further, it becomes possible to set the accurate white reference for the optical device, and the advance / retreat of the white reference to the reading position can be realized without providing an independent driving means.

By providing the image reading device having the structure of the present invention integrally with the fixed original reading type image reading device,
It is possible to provide a device capable of efficiently performing reading with high positional accuracy, simultaneous reading of one side and both sides of an opaque original, and reading of a transparent original.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional side view of essential parts showing an embodiment.

FIG. 2 is a schematic side view showing another example of an automatic paper feeding unit.

FIG. 3 is an explanatory view showing another example of a light amount control means at the time of reading a transparent original.

FIG. 4 is a side view of a main part showing still another example of the light amount control means at the time of reading a transparent original.

[Explanation of symbols]

 1 Fixed Original Reading Section 2 Moving Original Reading Section 11 First Light Source Lamp 12 First Optical Device 13 First Reading Optical Path 14 Reflecting Mirror 17 Carrier 21 Second Light Source Lamp 22 Second Optical Device 23 Second Reading Optical Path 24 Reflecting Mirror 32 Machine Type sensor 33 Optical sensor 35 Paper feed roller 36 Separation pad 38 Energizing spring 40 Cam 50 Bottom guide plate 51 Document passage 52 Top glass 53 Transparent platen 54 Transparent platen extension 62 Switch 63 Reflector 65 White plate 66 Return spring 68 Upper claw 69 Lower claw 70 Protrusion 71 Locking protrusion A First original reading position B Transparent original reading position C Second original reading position

Claims (8)

[Claims] 1. A first light source lamp (1) is provided on one side of a document passage (51).
1) and the first optical device (12) are arranged, and the second light source lamp (21) and the second optical device (22) are arranged on the other side. Second light source lamp (2
The guide surfaces on both sides of the part where (1) is placed are transparent guide plates (52, 5
4), the reading optical path (13) of the first optical device (12) faces the second light source lamp (21), the second light source lamp (21) is turned on, and the first light source lamp (11) is turned on. A double-sided image reading device characterized by turning off the light and reading a transparent original through the reading optical path (13) of the first optical device. 2. A document moving type double-sided image reading device which is arranged adjacent to a fixed document type image reading device having a fixed transparent document table (53), wherein the first optical device (12) is transparent. It is mounted on a carrier (17) that runs along the platen, the first optical device (12) has more reflective surfaces than the second optical device (22), and the second light source lamp (21) has a first reflecting surface. 2. The double-sided image reading device according to claim 1, wherein the illuminance is lower than that of the light source lamp (11). 3. The double-sided image reading apparatus according to claim 2, wherein the reflectance of the reflecting mirror (24) of the second optical device is higher than the reflectance of the reflecting mirror (14) of the first optical device. 4. The illuminance switching means (62) is provided in the power circuit of the second light source lamp (21), and the illuminance switching means reduces the illuminance of the second light source lamp when the original is a transparent original. The double-sided image reading apparatus according to claim 1, wherein 5. An opaque original reading position of the second optical device (22)
The original guide surface on the non-reading side of (C) is formed by an opaque guide plate (50), and the second light source lamp (21) is provided with a reflector (63), which reflects the reflected light of an opaque original. 2. The double-sided image reading apparatus according to claim 1, wherein the light is focused on the position (C) and is not irradiated on the reading position (B) of the transparent original. 6. A paper feed roller (35) for feeding an original into an original passage (51) and a separation pad pressed against the peripheral surface of the paper feed roller.
The double-sided image reading apparatus according to claim 1, further comprising: a separating pad pressing force releasing means (38, 40), wherein the pressing force releasing means (40) is provided when the original is a transparent original. The double-sided image reading device according to claim 1, wherein the pressing force of the separation pad (36) is released or reduced. 7. A mechanical sensor (32) for detecting a document and an optical sensor (33) are provided on the upstream side of the document passage (51), and the mechanical sensor (32) detects the document. 7. The double-sided image reading apparatus according to claim 1, wherein a transparent original is read when the optical sensor (33) does not detect the original. 8. The double-sided image reading apparatus according to claim 1, wherein the first optical device (12) is mounted on a carrier (17) movable along the document passage (51). Is provided with a white plate (65) which is guided so that it can be freely advanced into and is biased by a return spring (66) in a direction to exit from the document passage (51), and an engaging means (69) for engaging the white plate with the carrier. , 70) and an engagement releasing means (71) for releasing the engagement, the double-sided image reading apparatus according to claim 1.